Jump to content

Triumph - That was a year that was..


Bfg
 Share

Recommended Posts

Good morning,  and hey ho it's very nearly the weekend.. A couple of days ago, Wednesday, I collected Katie, from Wolverhampton.  Although not all as pre-planned. .

Having posted on the TR forum that I was about to, my friend Rich  from our local club group, who meet at The Alma, Copford, nr Colchester, once a month, dropped me a line to say that he would be glad to give me a lift up there and to be a shadow vehicle for the trip back.  He had a couple of stops to make to suppliers en-route anyway, and he'd enjoy the day out.  OK great, very much last minute but the prospect of not having to use a taxi and public transport to get up there, and equally having someone to watch our tail on the way back was very welcome. I cancelled the train tickets and got something close to 40% of their value back. That'll pay for lunch.  You've got to love the way the ticket office charge a five and half quid booking fee and then ten and a half quid cancellation fee !   Nevertheless, thanks to Rich I also saved a £10 taxi fare from my apartment to the station, and it meant that I didn't need to get up quite so early.  <_<

Rich collected me and after a quick cuppa we headed off up the A14. Traffic when leaving at eight in the morning was pretty clear and our timing was to go around Cambridge just after the 9am rush hour had cleared.  All was well, but then there was a traffic accident ahead and we were stopped in the fast lane for the best part of hour.  No "leaves on the track" though.  According to my preferred schedule we got up to Wolverhampton, and their local pub (the Storehouse) for midday, just when it opens for lunch.  I don't suppose you can beat the value of two meals and two drinks for £13.50 in many places nowadays.  My chunky steak and mushroom pie with big fat crispy chips and fresh garden peas was excellent, as was I gather Rich's culinary delight.. faggots and mash.   I guess we arrived at M&T shortly before 1:00.  The car was outside and washed off ..so looking sexy in red, in the bright but hazy sunlight.

Rich took the opportunity to sort through and buy some more spares, while Mark and I discussed our way through our final job list.  Again all was well.. that was until I started the engine, and there was a loud whine from the gearbox or clutch.  What the..?   Well, it transpires that a similar but lesser noise had been apparent before but then had gone away again.  For some inexplicable reason, after the car had been stood for a week and then just been pulled out of the garage, that noise was now back ..but with vengeance.  Not a rumble, but a pronounced whine. 

I must stress that Mark's involvement in the gearbox and overdrive saga was that of being a very helpful third party, who had removed the 'box when the engine was lifted from the chassis, and then he delivered it to Ken @ Classic Transmissions for rebuild.  M&T refitted it again and the engine/gearbox assembly was fitted back onto the replacement chassis.  That should have been an end to it, but it subsequently leaked, which necessitated it being removed again ..this time of course from the reassembled car.  He then delivered it again to Ken to be checked over.  The gearbox was found not to be the cause of the leak and so it was again refitted.  Then the overdrive was removed and taken across to O/D Spares in Rugby.  That was found to have a hairline crack in its case, and so was exchanged.  M&T fitted that and again tested things.  Job done.  And in the spirit of providing truly excellent service ..they swallowed the cost of the labour (gearbox and overdrive in and out).  

Now with this noise, Mark was again caught in the middle. It was agreed that we would quickly run Katie  over to Ken (Classic Transmissions) for their appraisal, and Keith the mechanic would join us there to discuss what might happen next.  And so as Rich packed his newly acquired bits into the car, Mark and I amicably shook hands and it was time for me to take the whirring noise issue to Ken.  I followed Rich down the lane and up the road ..and before we'd gone a mile the noise stopped completely.   

Thankfully Rich was my witness ..that I wasn't making a big fuss about nothing, but still the noise had gone.  We put it down to the new thrust bearing supplied with the Borg & Beck clutch (I had fitted myself).  It was great to catch up with Ken though.. as it's been six years since I took my Jag gearbox to him for its rebuild.  At that time his wife had just died and his son was diagnosed with cancer.  Thankfully his son, who I met on this occasion was a picture of health.  More so perhaps because of his full head of hair and truly excellent wavy beard ..that he grew in defiance of the side effects of chemotherapy.  Apparently throughout the treatment he didn't suffer any hair loss at all.  Brilliant to meet him and great to now see his working with enthusiasm and in-depth knowledge alongside his father. 

I expressed my thanks and also to Keith who had been instrumental in the reassembly of Katie's  mechanicals.  And so again Rich & I hit the road.  Next stop., Birmingham to one of his suppliers.  Whereas I would have gone back onto the M6 and then down into Birmingham on the Aston Expressway, Rich was following directions given by Mssr Garmin which I guess was heading the most direct route ..though a host of traffic lights and the black country condominium of towns.  Bearing in mind that I neither knew where I was going (which turned out to be nearby Edgbaston University, to the south of the city), and am very un-familiar with driving this car, and perhaps a little anxious that everything was going to be OK..  We did well enough to arrive together.  

That business was soon concluded, and so we headed back into the metropolis.  After the sat nav took us around a roundabout rather through an underpass to the A38, I took the lead out to Spaghetti junction and the M6 home.  Katie  was running well, and quieter and smoother too, for the first time we were driving on her pressed-steel / balanced wheels.  I kept my eye on the minor ..but ironically more important, gauges to see that nothing amiss was about to happen and otherwise kept a listening watch for anything out of the ordinary.  There is a slight metallic chink over some road imperfections, but I couldn't say if that was from loose items within the car, or boot, or doors (no trim panels in place) ..or whether that noise was perhaps from the exhaust just flexing on its rubber mounts and lightly making contact with the chassis.  Gearbox and overdrive were each working fine, and Mark had again excelled in the detailing of his service by somehow minimizing the rattles from door mechanisms and side glass. 

I noted vibration from the rear end (a rear wheel or the drive train) at lower speeds, around 50mph, but this was all but undetectable at 65-70mph (2250 - 2500 rpm in overdrive) so that set my cruising speed.  Btw, I say rear end because there was very little wobble felt though the steering wheel.  I could also feel engine vibration, while at town traffic speeds, which I mostly attribute to the fan extension ..which is atrocious un-true on this particularly engine.  But on the whole ; the car was verging being an acceptable drive.  I wouldn't go as far as to say civilised ..and definitely not refined, but Katie  was at least revealing possibilities.  I'd had a taste of those way-back-when I drove MIke's (TR4A with surrey top)  and Rich's very own first-class TR4. That excellent occasion had been on a sunny summer's evening and along twisty country lanes, which of course is a very different environment to driving along one of the country's busiest motorways at 70mph, where the wind buffeting and tyre noise from all traffic is relentlessly intrusive. 

I don't suppose it's going to be pleasant in any 1960's open top sports-car, but still.. the M6 soon passed under the tyres, and off we headed east along the A14.  Totally unexpected there was a loud and distinctively metallic rattle from the engine. I happened to be in the fast lane overtaking, and Rich was following two or three cars behind me.  There must have been a guardian angel watching over us because I immediately spotted an exit ramp less than 1/4 mile ahead, and so after a quick check in the mirrors I slipped across the three lanes and directly off the dual carriageway.  Rich safely managed to do the same and followed me up the ramp as I coasted into a farmer's gated field entrance.  From the driver's seat, the engine clanking at tick-over sounded like a big-end had given up the ghost. Oil pressure was down to 20-25psi.  Rich was standing there alongside me even before I could find the bonnet pull.  And then again before I'd even lifted my bulk out of the seat - he'd diagnosed the water pump pulley was flaying around.  Too hot to put your hand on it Rich.! 

The immediate thought was that the water pump's bearings must have disintegrated.  Again fortunately, this water pump was of the bolt-on pulley type, so out with the tools (I had taken them up to the car on my previous visit).  Rich levering down on the fan-belt stopped the pulley from turning, enabled me to undo the lock nut.  The pulley pretty much fell off and Rich spotted a bit fall to the ground.  I marked the spot with a small socket and rolled the car back to see what we might find ..but there was nothing much there. Perhaps just a chipped off piece from the inside of the die-cast aluminium pulley.  The groove for the woodruff key in the water pump's spindle was full of black dust. Clearly there had not been a key fitted.  How it had lasted this long in service will remain a mystery, but the really quite extraordinary thing was that Rich had just bought three or four water pumps from Mark ..and had them in his car.  And a couple of those had bolt-on pulley wheels which had already been undone.   Katie's  water pump bearings were free running and intact, and it wasn't leaking.  Although the top face of the water pump had been well chafed by the loose pulley (..evident as the excessive rattling noise) the spindle itself was also fine.  

We borrowed another pulley off one of Rich's newly acquired pumps but unfortunately, with the roadside tools we had, we couldn't get its woodruff key out (without risking damaging it) so we likewise fitted this replacement pulley without one.. but with a thick washer and another nut.  Pretty soon we had things back together again. And as we sped off along the A14 again (next turning was the A1 motorway, so we had been lucky to find a solitary slip-road to pull off).. the car / engine was quieter than I'd previously known it.  So I guess that pulley had been turning but rattling a little loose since I bought the car.  

Next stop was a filling station, as the gauge was reading empty.  It had £30 of fuel in the tank when we left, but the gauge's reading is not linear and soon reads nothing.  During our roadside stop, I had spotted a drip of petrol from the pipe between one carb and the next, and so Rich secured it a little tighter with a cable tie.  Naturally, I cannot say how much petrol had been lost to the road since Wolverhampton.  Fuel pipes were on my list to be replaced anyway.!   The pulley had started to make a tinkering noise again so we pinched up that nut for the next leg of our journey home, via a quick diversion to Bury St. Edmunds to drop off some more bits to a local supplier.  While Rich was attending to that I removed the water pump pulley's nut yet again and this time also added a lock washer.  A more modest pace saw us to my home just as it was getting dark. Rich had another half an hour to go. 

It had been a long day,  350 miles would have been a long day in many a modern car, but with half of that in Katie  it was ever the more so.  Although we had just a few spits of light drizzle the weather had been overcast most of the day but very mild.  I drove back with the roof down, in a long-sleeve shirt and sleeveless quilted vest / waistcoat, and of course my bobble-less woolly hat. This was with the heater valve almost closed, and I was comfortable enough into the evening. 

All in all then, the journey bringing her home was a success.  Rich is good company to be with, interesting and knowledgeable, a reliable wing-man and a blessing when it came to roadside repair ..and parts supplies !  He's even allowed me to buy one of his water pumps at a very generous price.  Thank you Rich.. You deserve a TR medal for your dedicated help and support to new members / new owners.  

Katie  is now back to where we were three months ago ..save a very much more solid foundation to build upon.  Although most items on our job list are still to be tackled - there's a host of jobs now done by Mark and his Team ..that hadn't even made the job-list.  The chassis is reinforced, both in the usual places and otherwise where I wanted, there a jacking pads to protect the main rails from getting dented in, and it's freshly painted and wax injected.  The body is now sitting on new rubber mounting pads and is riding square, and the outer sill has been replaced, the body shell made solid again, and the door gaps very much better adjusted.  All the suspension has been checked, and although the ride height is still to be adjusted, it ought now be easy to do.  Many other jobs have been done, some of which I specifically asked for (like replacing every brake flexi-pipe) and others Mark has done or had done out of his own kindness to help me along the way (..door check straps, the drain pipes from the fresh-air-plenum, are just two items on what would be a lengthy list).  And he's gone beyond the call of duty (mostly providing the labour at his own expense) to help get the gearbox and overdrive rebuilt. I am indebted.   BIG Thank you to M&T, Keith the mechanic, Classic Transmissions, and also Overdrive Spares. 

Now it's down to me to both get on with Katie's ongoing recommissioning ..and to enjoy driving her - because surely that would be the best way to honour those who have helped me along the way. B)

Pete 

        P1390348s.thumb.JPG.560c5d88f4e1f45c10dfffc4f52c9036.JPG

 

P1390350s.JPG.2a634d9df00e43dccfb2736839aa5b42.JPG      P1390349s.JPG.195a19f40b2d309aa7303b947c3aca52.JPG

P1390353s.thumb.JPG.9372eecc9443aec465a5e986f11acbfe.JPG   P1390354s.JPG.6ac3052aad7d50655ce4fc4e62f34ad1.JPG

^ Precision engineering .. roadside version.  I might add that the chunky molegrips and claw hammer were the tools Rich had with him  :D

P1390345s.thumb.JPG.cef929ad156686d335edca6a3f80ee30.JPG

^ Rich, wing-man, navigator extraordinaire, and able spanner man too  ..as I watch on from behind the camera !

 

P1390362.thumb.JPG.bfc315d4084c043ec868a237a24a9160.JPG

^ The morning after Katie on her pressed steel wheels, sitting a little high, but we'll sort that out in due course.

First task is of course to fit a woodruff key to that water pump pulley and to order new E10 proof fuel pipes along with decent clips.

That's it for today.   Triumph Sports Six Club meeting at Duxford on Sunday 5th. 

Hoping to be there.

Pete.  

Link to comment
Share on other sites

I was sitting on the edge of my seat reading of your Triumphant return.  It is often the case that a car which has had extensive work and much dismantling and reassembly will have a few wobbles until it settles down to being used again.  Fortunately, you were able to overcome the difficulties and complete the journey in style. I like the steel wheels and the car looks very smart.  Will the ride height adjustment be a matter of eating more pies, or will it require shorter springs?    

Link to comment
Share on other sites

Thank Ray,  Yes indeed, it's a little odd that even things which haven't been touched suddenly happen to fail or be a nuisance.. I don't recall things fixing themselves though :rolleyes:

Katie  is without bumpers at the moment, but the spare wheel and tools are in the boot along with a gallon of fresh water and a similar volume of engine oil.  Pies would be nice but too mid-ships I fear, and not enough for how I'd like her to be sitting (..in rather on top of her suspension).  Rich has suggested loosening the suspension fastenings and taking the car for a drive across a field, and then without jacking the car up to re-tighten things up again.  That may help a bit but again I rather suspect not enough.  So very likely I'll be refitting the car's original / previously fitted rear springs again.  With new poly-bush collars that might then be where things should be.  I just need to check that the car then sits evenly side to side.  If not then spacers are available to correct that.  The rear I'd like down an inch half to two inches, the front I'd like her down about inch.  I guess I'll need to borrow a spring compressor to do the fronts. 

Of course it might just be that Katie  is keen to show off to inquisitive TR enthusiasts the additional chassis bracing she now has ..or perhaps it's to show the skeptics that those mods were really not at all that heavy  ;)

I too like / prefer these wheels to the wires. I need to find a set of TR6 or perhaps Spitfire hub centres to finish them off a little, but I'm pleased with the look.  I even like not having the bumpers on, but I don't know if I dare to use the car like that.?   I might only guess that even minor body repairs are even more expensive than bumpers. 

Pete

 

Link to comment
Share on other sites

^ you might be right, to a degree, but I'd like her 1-1/2" to 2" lower both front and back.  And that's just not going to happen. 1/4" perhaps but not that much ..unfortunately.    

. . .  Evening all,

I started making a list of the jobs I've been doing since I got Katie  back last Wednesday evening, but I reckon those two-dozen items would make for pretty boring reading, so I'll just mention one topic at a time.  And as the current issue is fuel peeing out like its a Belgium fountain, I guess I'll start off with that. . .

P1390493s.JPG.4e63a2d3a10e14260968771560ff3c0e.JPG      P1390489s.JPG.18c1d7dd130e0d874417a29cf406dd8c.JPG

^ This was in the float bowl of the front carb, and then rather similar in the rear one. The glass bowl of the petrol pump was worse and had larger flakes, perhaps black paint ?

However I should add that I'd not checked them before now and so this sediment might be 20 years old, and the issues I've had may be from my trying to temporarily fix leaky joints.  In brief from forcing old rubber pipe over sharp edged metal tube, whereby the inside of the rubber pipe is scraped and tiny rubber slivers then find their way under the float chamber's needle.  I guess I'll never know for sure.  

Anyway, it isn't worth mucking around with ..for the sake of £10 for a meter of 1/4" rubber pipe (ethanol stable) and £1 each for new and neat little stainless clips.  These I bought from the TSSC club shop at Duxford - Thank you to those unsung heroes who provide a great service, not only throughout the year by post, but also in providing advice and the convenience of being able to collect parts from an event ..on a Sunday. 

Katie's  fuel pipe run was like this  (..tidied up a little but otherwise pretty much as bought) . . .

1542103412_TR2021-03-14001as.thumb.jpg.f39454f3e31f96ade120971414779cd3.jpg

^ Rubber pipe from the pump ( Rear LHS of the engine) with 1/4" connection, going to a chromed-copper-tube (approx 5/16" OD) which sort-of / just about / almost swept around to a support bracket under the thermostat. From that end - plastic / hard rubber 'flexi' pipe to an in-line fuel filter, and then to the front carb ( Front RHS of the engine ) with its 1/4" pipe connection on the float bowls.  From there thin plastic pipe (5/16" fitted onto a 1/4" connection) went to the cross-over-tube (5/16") leading to a similar thin plastic pipe to the rear carb. You'll note there were no pipe clips on the cross-over-tube.

The unsupported length from the bracket on the front LHS  of the thermostat - sagged uncomfortably close to the fan-belt pulley.  Naturally this was not helped by the span, nor by the weight of fuel in the filter.  You might say that I paid good money for these leaky issues, with there being no gasket for the forward float bowl, and its pipe connections seeping. 

So, this is what I changed things to . . .

P1390500s.JPG.103825b725b9b99bbb34be72f5503eab.JPG     P1390499s.thumb.JPG.af4b81ca473c0fdca02b78d02992a0f1.JPG

^ The chromed-copper-tube from the pump to the thermostat was reshaped to follow the contour around the front of the rocker cover and to tuck inbetween it and thermostat.  The rubber pipe from there to the filter was swapped out (now 8mm), and the filter moved close to the carb, where it was better supported and further from the exhaust manifold. The rubber pipe from there to the forward carb was also changed for new (also 8mm) and a sleeve inserted into its end ..to take its bore down to the 1/4" connection of the float bowl.  The pipes to the cross-over-tube remained as they were, because by this point I'd had enough of leaky joints and was about to buy 1/4" fuel hose of the latest ethanol spec.

Despite cleaning out the pump's glass bowl and the sediment in the float chambers, I then faced repeated needle jets sticking  . . .

P1390498s.JPG.d9b841458ae75637e510715239845af7.JPG

^ the float bowl's needle is by any other name a shut-valve, actuated by the float floating on the petrol being pumped into the float chamber. When that needle doesn't close that valve (because a speck of debris is holding it out of its seat) the fuel continues to be pumped into the float bowl. In short time it overflows and petrol squirts out of the breather hole, situated just under the pipe connection.  On the rear carb, this hole points towards the bulkhead and so a squirt of fuel shoots out and splashes everywhere and vaporises in the vicinity of exhaust manifolds .. not quite the ideal !   The front carb's vent points towards the inner wheel arch ..so again when that overflows - petrol similarly splashes off that surface, before running down the engine-bay's bodywork ..to then dribble directly onto the main chassis rail.  I guess its just tough luck if any of the paint isn't petrol resistant. Fortunately Katie's  was.

Having bought the 6mm / 1/4" rubber fuel pipe at Duxford on Sunday.., today I swapped it all out.  This is what I now have . . .

P1390511s.thumb.JPG.fb4eac2e2e534a9cad424161c658cb5f.JPG

^ all the rubber fuel pipes have now been replaced, and while at it - I re-routed the tube to go around the back of the engine to feed the rear carb first.  I'm biased but I think it now looks to have been designed ..to be this way. B)  

To do this, I reshaped the chromed-copper-tube, yet againso that it now sits parallel and close to the battery (..now well clear of HT leads, the hot water / heater return pipe, and the fan pulley.  I've used a velcro strap to loosely tie it, and the rev-counter cable, to the earth lead. 

On the far side ; the chromed-copper-tube bends upwards, and from there a new piece of rubber fuel pipe goes directly to that rear carb.  The new rubber fuel pipe is 1/4" and so I soaked its end in hot water to soften it enough to stretch over the 5/16" copper pipe.  

The distributor's auto-advance vacuum pipe I've left where I'd previously moved it to, behind the thermostat (..away from the fan belt) and I've removed that horrid little sharp-cornered, pain-in-the-arse-to-remove fuel-pipe support-bracket, which was clamped there by the thermostat cover's bolt.  I'll have to get one of those 90-deg elbows for the vacuum pipe to tidy that up a little more.

P1390506s.thumb.JPG.560839bcb1fd818f8f0c530fefc61045.JPG

^ despite the impression given by the perspective in this photo.. the new fuel pipe's route is well clear of the exhaust manifold.   I've discarded the cross-over-tube  ..and now simply run the new rubber fuel pipe from one carb to the other ..that gets rid of two potential leaky joints, and the steps in size.   The speedo cable goes down passed the steering column, before sweeping back to the gearbox (..you can see it cable-wrapped to the loom at the bottom of this photo).  And the fuel pipe loops smoothly around, from one carb to the other, on the outside of that cable ..so it cannot stray anywhere near the exhaust down pipes, nor the steering column.

Job done, and another tick on the "replace every item of perished rubber" list.

I haven't refitted the inline fuel filter, not least because it's both big and ugly.  I hope with everything now clean.. the gauze mesh in the fuel pump's glass bowl will do the job.

We'll see.! 

Pete

Link to comment
Share on other sites

On the Triumph Sports Six Club forum someone posed the question - why did they run the pipes around the front ? 

For those who like to look under car bonnets, here's my reply. . .

 

I'm pretty certain the original / standard routing of the fuel pipe was like this . . .

67TR4A0022.thumb.jpg.13be3597d851d501a0f3a6e57b2324b6.jpg     67TR4A0027.thumb.jpg.04b401fd52a502afe84bb506e4d88243.jpg

^ From the fuel pump, a metal tube (no rubber connector needed) ran forward and around the thermostat and most the way across to the forward carb.  This continuous tube was a 1/4" and so even the last rubber pipe had no step in size.  Their fit was matched and I don't believe any pipe clips were originally fitted on the connections.  

858372868_w445_Fuelpipeclip.jpg.ba88072d0ffb80f517b27aec08655824.jpg

^ The fuel pipe support bracket from the underside of the thermostat was like this, and had a specially formed rubber holder, which similarly supported the auto-advance vacuum pipe.

Various design of cross-over-tubes (from the forward carb to the rear) according to whether early SU's (TR4) or Stomberg (TR4A ..for a while), or later SU's (later TR4A's) were used. But again in each case the metal tube was 1/4" ..so the rubber connector pieces didn't have to deal with any step in connection size. 

283591.thumb.jpg.d6591eef913f55d84d0b0a7832a02594.jpg

^ This is a TR4 with SU's and the earlier type air filter.  The in-line filter is of course not standard, but the point here is how simple the cross-over-tube between carburetors is. Again the metal tube size is the same diameter as the connections on the float chamber caps.  These earlier SU's had a different cap on their float bowls, and the pipe connections were inline rather than diagonal. 

When the later TR4A swapped back to using SU's and the air filter was changed to the oval paper-element type, that you see on Katie.  These were through-bolted, and two P-brackets were used to support that cross-over-tube . . .

66TriumphTR4A44s.jpg.cf0540e794600db019908968e7c9605b.jpg

^ it's surprisingly rare to find a car with these air filters and the cross-over-pipe still on it.  The clips on the rubber pipe were not originally specified. 

As you might gather Katie's  was a hash up of bits n' pieces of different sizes.  Going back to original would have elevated most of the issues I had with getting pipes to fit over different sized tubes, but in my opinion those fuel pipes spanning across from the front of the engine and the cross-over-tube between carbs is rather ugly.

- - -

Why did the pipe go around the front ?  Well I think the answer to that is two fold. The first being that traditionally engines fitted out to be run on a test bed, so things like the coil were bolted onto the engine as was the fuel system from the pump onwards.   Not necessarily Triumph's but many pre-war chassis cars were assembled to be started and driven as a rolling chassis, even before a body shell was fitted. This was useful where there was a split in the production line, and cars had to be moved from one part of the assembly plant to another.  

The second half of the answer probably lies with these things being carried over from the TR3 where the nose of the car / the bonnet enclosure came all the way back to cover the radiator,  and of course 'Why not ?' . . .  

221865699_TR3a-WP_20160602_19_51_41_Pro.thumb.jpg.1c44b073687668c6974bd98f4669c009.jpg

^ why not ?  in 1950's maintenance was more important than everything being neat.  The car's heater return pipe runs back along that side of engine, as does the conduit for the oil pressure gauge. The HT leads are rarely tidy nor the wiring to the coil and distributor. The rev counter cable is down there too.  There's not a whole lot of space around the back of the engine, and so when the engine with gearbox is lifted out or refitted.. it's quite common for the back of the block to clout the bulkhead.  Any pipe back there would be vulnerable.  You'll also note that the carb's float chambers are forward of their venturi.  The car's heater valve and pipe and the pedal assembly with master cylinder, a bundle of wiring loom and the solenoid nearby the starter motor, and of course the close proximity of the bulkhead ..leave very little room for them to be on the rear side of the carbs. 

So I think the simple answer, in technical jargon..  is that it was just "easier" to run the fuel pipe around the front, along with the auto-advance vacuum pipe.

Pete. 

 

Link to comment
Share on other sites

 I've now done a couple of dozen jobs on the car since I got her back, but now I really need to address the ride height before anything else. The car's handling is what I'd regard as uneasy and unpredictable, and because of that is verging on the dangerous. 

When I bought her - she was a little low on the back and sitting lop sided, but when I over-did through a corner she settled into a very controllable slow-motion-like 4-wheel-drift and looked after me.  Presently, she's just about OK down a dual-carriageway, but coming off a curving slip-road, or driving down a straight country road with undulations, or twisting through even modest corners ..the positive camber on the rear wheels wind up to make the car feel as if it is on the brink of twisting over and breaking away.  My old Mk.2 Spitfire had wind-up rear suspension ..but it had such a low centre-of-gravity that it was great fun to drive.  But not Katie  as she presently is. 

Russell, in our local Triumph Sports Six Club invited me, in Katie, to join him in coming across to Duxford. He and a friend drove across in his navy-blue Stag. I asked if he was going around the A14 or across country, he didn't mind. As it happens fuel leaks prevented me coming in Katie,  but after sorting the fuel pipes out I test drove the car and realised that a cross country jaunt with this suspension geometry would have been a horrid drive and possibly inviting an unscheduled expedition into hedgerow brambles.! 

 

P1390247s.JPG.7c4b5bf61144096cef7a70df12143522.JPG

Like many IRS cars, the TR's ride height directly effects the camber, which I gather should be around neutral when unladen and an increasing degree of negative camber (spread the footprints wider apart) the more it is loaded ..when cornering.  Negative camber helps the tyre's footprint stay flat to the ground during cornering, even as its side walls are deflecting. 

When the springs are harder and longer than they should be (I'm suspecting TR6 springs have been fitted).., the ride height is very high and, because of the geometry of these trailing arms, the wheels (as you can see above) adopt a noticeable amount of positive camber.

When cornering ; an excess of positive camber tends to tuck the wheel under its suspension, rather than the car squatting.  Less roll might seem to be a good thing but not when the car's higher-than-correct centre-of-gravity rolls the body over the axle ..which just makes things worse.  When cornering enthusiastically, the tyre's footprint (contact-patch to the road) moves to the outside of the tread.  With still harder driving, the effective contact-patch might be reduced to perhaps just a quarter of the tyre's tread, and then all it takes is a road irregularity to loose traction.  The narrow width of these cars, and therefore its narrow track, amplify this scenario.  As of course does the nature of a driver's sportscar ..which encourages an 'enthusiastic style'. 

Positive camber on the front make the car's steering a little twitchy and tends to induce over-steer ..so not only is the suspension winding itself up, but so is the steering.  This car's suspension caster has similarly not been checked.. it was just bolted together. 

Brand new tyres with very soft walls and those being 165/80 section, rather than low profile, would also contribute to the tyre tucking under.  Again fitting those tyres to narrower wheels (4" rather than the wire wheels at 4-1/2") works against us.  And then, it's also very probable that a predetermined (..well accepted anyway !) amount of chassis flex contributes to negative camber, and my chassis stiffening mods have altered that, whereby I'll need to adjust for a little more negative than standard. We'll see.

NB. the TR6 springs were up-rated by the factory, due to that car's excessive squatting under accelerating power which caused their steering to go light and their twin exhausts to drag. The TR6 also has an anti-roll bar and wider profile tyres as standard to help keep its grip. 

The front axle's tracking was checked and presumably adjusted by a tyre centre before I collected the car.  Of course i do not know what figure they used for their adjustment.  I haven't checked with a taught string yet but a careful visual check suggests little toe-out of the RHS rear wheels ..perhaps, according to a quick geometric calculation it's about -1/2 of a degree from being in line  My calc takes into account the TR4A's front-axle track being 1/2" wider than the rear.  Although not perfect I cannot see that as a significant issue.

I'm advised by my friend Rich, who has a few TR4's, that Katie  is not (noticeably) crabbing. . .

 

I investigated rear springs this afternoon, well the rear RHS one anyway.

P1390527s.thumb.JPG.ddc17231f7dea132f62e16c1eb6ad29b.JPG

^ I'd not done this before ..but the process is simple albeit laborious, insomuch as the half-shaft coupling needs to be undone from the diff.  With other wheels chocked, the handbrake needs to be off to turn the half-shaft around to undo all four bolts.  Sockets do not fit and so it's a two 9/16" ring or open-ended-spanner job.  Awkward when your working on the floor under a low car, even one on axle stands.  Otherwise, with the chassis supported., a trolley-jack under the trailing-arm takes the spring tension as the damper's tie-rod (one nut on the underside of the trailing arm) is undone.  Once that nut was removed - the trolley jack is gently lowered while the half-shaft is supported - to prevent it's gaiter from being damaged by it dropping down on the corner of the chassis rail.  That's all, the spring sort-of pulls out, but there's not quite enough room for the rubber or poly-bush) collar ..so that falls off.   

Comparing the new and old springs, sort of surprised me. . . .

P1390530as.thumb.JPG.4d996d7af35e0ebf6219cc8fb1b2bc1a.JPG

^ Replacement spring left, old spring right.  Although first impressions suggest they're different, they are the same length (11-1/2") 

And when weighed, they both come out at 3kg (bathroom scales are not that accurate but close enough for this). This suggests they have a very similar amount of steel in them. 

And then when tested under arbitrary load, of 24kg (three night storage heat bricks) . . . 

P1390532s.thumb.JPG.060b57fefdedacf6e8ccea9728758343.JPG

^ they each compressed by the same amount ..just 1/4".   For all intent and purpose then.. they appear to be the same specification of spring.

 

The tyep of spring collars were shown to me when I visited M&T and those were black poly-bush types of 7mm thick. 

P1390547s.JPG.22d672d4541a7a6d7a476a359bc73e49.JPG

^ New 7mm thk polybush collar left, old 5mm thk rubber collar right. 

According to those in the know, because of the suspension's geometry ..the difference in spacer (or collar thickness) equates to just a little under double its thickness in road height. So the difference in thickness here is 7 - 5mm = 2mm + 1 for the rubber being squashed a little more = 3mm, so that'll make 6mm difference in ride height.   

I put the replacement spring back in, sitting on a poly-bush collar at the bottom, in the trailing arm, but with the old rubber collar fitted at the top. Took the car around the block (which here in Ipswich is like a lap around the pavé track at Millbrook vehicle test facility) ..and low and behold that side is now 5- 6mm lower.  Exactly as predicted but never-the-less worth checking for peace of mind. 

Very oddly, the positive camber now appears much better.??  That changing was not something I had anticipated, nor something I can presently explain. I'll check it again tomorrow.

So, if the springs are the same, and the collars make such little difference - I'm still a little baffled as to why the car is sitting 40mm too high. 

P1390552.thumb.JPG.14457cdc89efca7349f91245c9677c10.JPG

^ The spring saddle looks to be standard, aside from the couple of extra corner-triangulation gusset plates and its colour of paint. 

I did however note that the body used to rest on the old chassis' spring hanger, and in fact the inner-wheel-arch bottom flange was chafing through the top of the cup on the RHS.  Whereas the body, sitting on the replacement chassis, is notably higher. The gap between the top of this spring hanger cup and the flange is now possibly 12mm (higher). I've just checked the RHS and that has something like 8mm clearance now.

P1390555s.JPG.f098dad4fdfafa64763be2afe99100ad.JPG

^ looking down into the spring cup of the trailing arm.  No spacer in there just the 7mm poly-bush spring-collar smeared in silicon grease. 

So where does any of this take us ? ..but around the block and back again ?

Well, my present conjecture is that the old rubber spring collar I fitted - was the best of the three removed from this car, and one was missing. Swapping back to this (best condition) one made 5-6mm difference in ride height.  Double that, and add a bit more for the even more squashed rubber of the spring's bottom collar ..and we'll have 12-15mm additional ride height, which together with the body now sitting 8-10mm higher on the chassis.. totals 20-25mm extra ride height.  Quite possibly the old springs are a little tied and so when loaded under the 450+kg weight of the back of the car ..that might account for the other 15mm or so difference in static ride height we now see.

Tomorrow I'll swap both rear springs for the original ones, just to try it and see. B)

Pete

 

p.s.  when fit recently repainted or powder-coated wheels, take a minute to run around the bolt holes with a blade to clean out the paint before fitting.  Possibly I should have done this before I gave the steel wheels to M&T to be fitted  ..but their mechanic should have known better and very quickly done it as a matter of course.  It's really bad practice to fasten structural parts or anything that's safety orientated onto a thickness of paint rather than metal to metal.  The paint will crack and flake, which may happen a few miles down the road ..and then the wheel nut will be loose.  Aside from that.. seeing cracked paint really pisses the customer off.

P1390563s.JPG.941d6e2a7a23bec6418eb23d22956ce5.JPG

Link to comment
Share on other sites

P1390579s.JPG.b2dcc257d194f3e98932d52253c4a989.JPG

Rain today, light at first progressively wetter..  as I'm not exactly keen on laying down and crawling under the car in the wet ..progress was slow.  Before I swapped the road springs back to what was previously fitted, I thought it prudent to first check that the trailing-arm's poly-bushes were not binding up.  When we collected the car, my friend Rich suggested loosening the bolts through the trailing-arm bushes, just in case they had been tightened up with the car jacked up, and were too tight to settle. With a host of other tasks and then fuel leaks I've only just got around to doing it.  

Rich had suggested I loosen them and then drive the car around the block, but I opted to do it a little different, not least because they would have needed to be re-tightened, and for that to happen I would have needed to jack the car up again ..for me to crawl under it.   So I first lifted the rear wheels onto blocks.  At the same time I loosened the bolts through the four trailing-arm brackets / poly-bushes (5/8" spanner & a 5/8" socket).

P1390585s.JPG.a79fd1b64971fc5ad781068c7c2b0e1f.JPG

..you can see the sort of wheel arch gap I'm trying to sort out. 

with the front wheels loosely chocked and the handbrake off, so the wheels were free to turn as they settle, I loaded the boot. . .

P1390587s.JPG.de0abfe2458fa4e020d81780908cfddc.JPG     

^ I estimate that's about 95kg sitting on a 6x2" timber, which together with my own weight (105kg) bouncing up n' down on the rear wings and rocking the car from side to side, ought to turn the poly-bushes in their brackets / on their bolts for this loaded condition.

And then still loaded, and without  jacking the car up, I crawled under and retightened those bolts.  Once done, and unloaded the bricks out of the boot and popped around to the local shops in the car, so the wheels were then sitting normally level to the ground.  The result of my efforts was to make things 5mm worse (ie.., raised) on both sides !  ??

Btw the LHS has a bigger gap than the RHS rear arch ..hub centre to the arch, by about 12mm, despite it having a thinner collar fitted above its spring.

It's still wet so I'll change the road springs back to the old ones tomorrow.

Pete.

 

Link to comment
Share on other sites

Half-shaft has now been swapped out..

P1390616s.thumb.JPG.10d97af2399712f94ee93e9efbe19767.JPG

^ the original from this car (top) and one I bought hoping it was OK below.  :huh: fingers crossed.

Rear springs now swapped out for those that were originally on the car.  

Five hours later, as I had to first swap the wheels studs over, and then had issues with one of the six studs holding the hub to the trailing-arm being loose / a stripped thread, the sliding handbrake mechanisms having no lubrication, and then again the handbrake cable mounting on the top of the trailing-arm being loose, no washer under it, and a binding nut.   It's all back together now but for doing the wheel bearing nut up.  Not turned a wheel yet so don't know what the ride height like is yet. 

Pete

Link to comment
Share on other sites

Yesterday Mathew (Puma-powered Spitfire) from the TSSC., very kindly drove down from Norfolk to give us a hand. Two minds looking at the same problems from different experience-perspectives, as well as another pair of hands when measuring toe-in, camber and tracking, was very useful and he's good company and an interesting chap to hang around with.   Mathew also has toe-in checking equipment which gave definitive, if at some times a little confusing, data.    I might add that the confusion was mostly on my part because I'd never used such no-smoke-&-one-mirror tricks before.  I'm old school and so still use a length of cord along with a tape measure and a spirit level. 

First thing though was to do the final task of swapping the half shaft out and replacing rear the suspension springs for those that came off the car.  I'd assessed that they were of the same spec as the replacement ones, but I figured the replacements were perhaps less 'tired' than the originals ..so with the old springs back in the car - she might settle lower.  That final task was to tighten the central hub-assembly nut up to the prescribed 100-110 ft lb.  which with my background in old bikes rather than cars, leaves me a slight disadvantage. To me (having never had a hub apart to see the bearing assembly & inner workings) that big nut appears to be a wheel-bearing nut, which with old cars I thought was "pinched-up tight and backed-off by one flat of the nut"  ..then put the split-pin in and it's good to go. 

However, the Triumph workshop manual, under torque settings (at the very front a manual with no index) it says "Rear Hub Assembly ... 5/8" x 20 UNF stub axle ... 100 to 110 ft. lb."   In part this information is copied across to the Haynes manual but their semantics confuse things by describing it as "Inner driving flange to inner axle (IRS), which doesn't tie in with either my jargon nor their exploded diagram.  Anyways up, the figures agree and so 110 ft.lb. is what it was done up to.  

We then went for a few miles test drive around Suffolk's unclassified and b-roads, pushing the car into corners as fast as other road users would allow.  Aside from a quick stop to lift the top off the carb's float bowl to clear its needle from sticking again, the handling felt much better.  In fact the car in general sounded and felt almost passable, albeit with rather light steering and a tendency to over-steer in faster tight corners where subsidence made the road surface uneven.  However, when we got back and measured the ride height (having rolled the car forward and onto a level packing (plywood under one wheel) - the car is sitting no lower with these springs than those M&T fitted.  It also remains higher on the passenger side than the driver's.   In summary, I might only attribute the better feel of the car to having two people in it rather than just myself.  

Mathew then got his laser and mirror toe-in checking device out and we checked the rear axles  . . .

Toe-in of the rear wheels and Tracking..

P1390627s.JPG.84c0eb4ff890fec485ac10b723f5de9d.JPG    P1390628s.JPG.8df4cd8f095dcb652311b0b81e9325f2.JPG

^ Having set up the mirror to the LHS rear wheel rim, the laser's red dot is reflected back to its gauge and centred ..as a datum to compare with. The laser is then left untouched as the mirror is moved to rest against the rim of the RHS rear wheel.  The reflected red dot now tells us what the difference in angle is.  As you can see in the second photo., that was recorded as about 13 minutes of a degree (ie., about an eigth of a degree toe out).   The workshop manual tells us that the axles (front and rear) should be set zero (neutral) to 1/16" toe in.  I could convert from 1/16" to degrees but for the time being we'll leave it ..as to adjust the toe-out to toe-in would involve re-shimming inbetween one trailing arm bracket and the chassis rail.  And Mathew reckoned that even removing just one shim would result in too much adjustment.. He has a Triumph 2000 with much the same IRS suspension as this, so I'm happy to take his word for it.  In any case although the device highlights this tiny inaccuracy, it doesn't tell us which (left or right) trailing arms is out of alignment.

Me, well I'm old school.. and I had a piece of cord to work with. . .

P1390629s.thumb.JPG.d4c2ffce12d876f436905197cd6df0f1.JPG

^ with the cord tied to the exhaust tail pipe ('cause I'm right-sophisticated with my engineering set-ups) and pulled taught around all four tyres (the cord clearing the sills and otherwise pretty close to being parallel to the ground) we could then use a tape measure or rule to measure front and back dimensions between each wheel rim and the cord).  Those dimensions were of course in inches or mm, and it's intuitive to see which wheel was pointing where.   NOTE : we did allow for the difference in width of front and rear axle tracks, with 5mm packers under the cord on each rear tyre.

The rear wheels were very close (measured as about 2 - 3.5mm out of track) but the front wheel tracking ..which I was told by Mark had been done by a commercial tyre centre in Wolverhampton, was 10 - 12mm toe-out.  Oops !  It is meant to be 0 - 1/16" toe-in.  

So we went for lunch ;) 

Thereafter we adjusted that, at the steering rack's tie-rods (..either end to try and keep the steering-wheel straight).  For this task - the laser & mirror was helpful and very much more precise than the cord and tape measure.  Accordingly, I've now set them to about 3-5 minutes toe in, but I also accept that's a temporary setting, as there's play in the steering rack itself. 

At the local TSSC evening meet-up a member kindly flagged this, as most likely being the rack's inner ball joint.  Again this is something that I would have thought M&T's mechanic should have noted and advised on ..perhaps asking if I wanted it exchanged or refurbished while the body was off.   It's noticeable enough, as is a wobbly rear wheel bearing, that they otherwise ought to have been flagged by the MOT.   Anyway, they're now just other items on my job list.

Checking the cord, now with the front wheels in line, revealed that the rear track was so close to being correct as to be of no concern. The cord, previously held out of true by the front wheels - corrupted our previous measurements at the rear.  Measured again, the rear wheel rim to cord dimensions were so close, on both sides as to be negligible, and indeed (if I recall correctly indicated) 1.5mm toe in.   I'll check that again because the recollection contradicts the laser readings, but 1.5mm, in or out, on a 15" rear wheel is pretty close ..and it may yet adjust when the ride height and the wheel's positive camber are corrected.    

Our second test drive confirmed that the steering was very much better now, with a little feel (rather than being a little too light), and so very much better feel in corners, in particular left-handers for some reason.  I still felt that the car was rolling over its suspension and skittish when pushed (or over pushed !) ..but still we had achieved a noticeable improvement for very little effort.   I leveled the floor by the patio before driving straight in (no reversing to wind-up the suspension) and we checked the ride height again and also looked into the positive (leaning out at their top) camber of the rear wheels.

Ride Height .   The ride height measured (wheel centre to underside of wheel-arch rim) as 405mm on the RHS, and 425mm on the LHS.  Checking against a spirit level across the car, we've determined that the LHS wheel-arch is 10mm higher than the other (down to body tub, wing shape or where it's fitted), so the passenger side will look higher by that amount.  The body is sitting some 8-10mm higher on this chassis, probably thanks to having new rubber body-mount pads inbetween the two.  And the poly-bush spring collars are each 3 - 5mm thicker than the old rubber ones and so, due to the geometry of spring to hub distance, would raise the rear suspension by 6 to 10mm for each collar.  x2 collars for each spring = 12 to 20mm increase in ride height.  I'm not sure I can do much about that, but to fit shorter / lowered springs.   But I'll wait to see how correcting the camber changes things.

Camber.   Unfortunately Mathew's camber checking device wouldn't work on this car, because there is no flat surface on the wheels for the device to fit it against.  Apparently it's often set against the flat of a brake disk.  So back to old-school ways of doing things.. ie., a spirit level set vertically from the ground and resting / steadied against the wheel arch. From this straight edge datum its easy enough to measuring the distances to the wheel rim.  BTW., for these dimensions to be accurate, 68 kg or thereabouts, in night storage heater bricks was set onto each seat (in accordance with the workshop manual.

The measurement itself is meaningless (because of wheel arch brow dimension is not accurate) but the difference in dimension between that taken at the top and bottom of the wheel rim - tells us the camber.  That is measured in mm but is easy to convert to angle when you know the diameter of the wheel rim (395mm in the case of these 15" wheels).  Each wheel measured 10mm or thereabouts of positive camber.  That equates to 1.45 deg positive camber when it should be +/-  0 to 0.5 of a degree.   Only with my 105kg bulk sitting on the rear wing / on the rear light did we get close to getting the suspension height change to adjust the wheel camber to close to being zero.    

At speed around a corner I'd fall off :help:  so I'll next need to adjust the camber by altering the trailing arm brackets. I'm going to try reversing which way around they are fitted onto the chassis rail. 

That's it. It was time for a quick cuppa tea, and for Mathew to look at some Caterham seats I have, before he headed for home.  

I know what's got to be done. It's a little frustrating that I'm having to do it, but I'm at least of a calm piece of mind to get one with it, possibly over the weekend.

Big Thanks to Mathew for his help, patience, amicable nature and positive motivation. 

He's taking an unscheduled break from jobs right now, and I wish him a speedy recovery. 

Pete.

 

Link to comment
Share on other sites

Yesterday was interesting, but not as productive as I hoped ..and my back now aches something rotten.   Nevertheless here we go . . .

Ignoring for a moment the ride height, which I hoped might be helped a little, with what I was about to do - the challenge was to adjust the rear wheel's positive camber. 

But firstly, I needed to ascertain where we were at.

P1390634s.JPG.3aba71ccebcbd26bc4f21991b0718406.JPG

P1390635s.JPG.f9080f90a2fa24ca812c5b46370b840d.JPG

^ eight approx 8kg night storage-heater bricks in each seat, half a tank of fuel, the spare wheel and another 15kg of weight in the boot to simulate normal load conditions.

The car is on the level having been rocked and rolled forward.

P1390637s.JPG.c52f784f2d630697444f41d0052b6dbb.JPG    P1390638s.JPG.72cc5f8dd1a737a8abcc390be0b1f87e.JPG

^ The spirit-level is standing on the floor and leaning against the wheel-arch brow, with a piece of wood leaning against it to hold it steady while I measure to the rims top and bottom.  The dimensions recorded (rear LHS) were 46.5mm top and 50.5mm bottom, so the top of the wheel was tilting out (positive camber) closer to the spirit level rather than being upright or slightly tilting in.

I did a scale drawing of this (on the computer in ACAD) and the angle equated to 0.73 degrees (positive). The TR4A workshop manual tells me it should be +/- 0.5 degrees. Personally speaking I would like to see zero to -0.5 degrees negative camber.  In any case the requirement is to alter the positive camber to negative by about 3/4 of a degree (have the wheel sitting vertically when the car is loaded or leaning in by about 3mm difference) or just a little more.   NB. the difference on the rear RHS of the car was the same 5mm / 0.73 degree positive camber.   It's reassuring when both are the same.

Now, working on the rear RHS of the car, only because that was easier in my present working environment, and with the wheel off this is what we see . . .

P1390648s.JPG.ef896c271841cfc8dfa21345a874be7d.JPG       

^ Taking the chassis rail as being level,  you can clearly see how the trailing-arm brackets adjust the camber of the trailing arm and therefore the wheel.  It ought, by the look of things, to be negative camber (top of the wheel tilting in) as the orientation of the brackets are correct for this car.  The camber does go to negative as the suspension is compressed. This is so.. when cornering - it's like putting the tyre at a very slight angle to stop it sliding sideways.  As it is the tyre leans outwards and the so is scrubbed further under the side wall.  This positive camber then is consistent with the car's ride height being more than it should be (the springs are not compressing enough).

Looking on Buckeye Triumph's report on adjusting the camber ;  I read this . . .

58600545_Trailingarmbracketseffectoncamber2.jpg.e3e7df85046368aacb5816864a4e9760.jpg

^ This records three different bracket shapes, 1, 2 and 3.  each marked with the corresponding number of notches on its top edge.  

Type-1 has the trailing-arm pivot / axis bolt (where the rubber or poly-bush goes) just 3.2mm below the centre of the bracket (between the bracket's two mounting bolts). NB. This type-1 is what I have.. seen to the left of my photo (above). 

Type-2 has its pivot/axis-bolt 9.35mm above the centre of the bracket. This type of bracket is what I have (outboard by the sill) seen to the right in the photo above.

Type-3 bracket doesn't concern me because I don't have those (they're sometimes used on the TR6), but for record their pivot/axis-bolt is some 16.8mm below the centre of the bracket. 

3D-2D means Outside a type-3 bracket with notches Down, used in conjunction with an inside type 2 bracket, also with its notches Down.  In this configuration the camber between the brackets is -4.16 degrees ..which because of the trailing arm's geometry gives -3.3 degree (negative camber) of the wheel. (it say 3.61 degrees in another table). Another row starts with 2U-3U whereby the U signifies that the bracket is orientated with its notches UP.   

Katie  presently had the configuration I've highlighted in blue. 2U-1U ..that is type-2 brackets with their notches facing Up on the outside, and type-1 brackets, also with notches Up on the inside (nearer the centreline of the car).

Editing that table into what is pertinent to me at this time .. insomuch as I only have two type-1 brackets and two type-2 brackets to play with, let's clear all the other permutations away ..and so this is what we see . . .

1178530909_Trailingarmbracketseffectoncamber3.jpg.d33f5f609e4b26f8e78dc444d7ce892f.jpg

^ The configuration Katie  has (correct according the manual) is again highlighted in blue.. Outer ; 2 with notches Up, inside type-1 bracket also with notches Up. 

I want more negative camber by at least 0.73 of a degree ..and the table says to reverse & invert (in red) the brackets I have. That it says would alter the camber by 0.6 degree which is very close to what I want, and the most these particular brackets will give us.  

However to me it doesn't make sense.  Surely if you rotate the brackets 180 degrees ..the angle between them will be the same.?   I wasn't convinced ..but at the same time I remained uncertain, as this report is reputed to be accurate.  Perhaps I was missing something.?  So., I took the brackets off and did what it suggested . . .

P1390651s.JPG.4b067e6d359b5503a0f6f61fbd13d04a.JPG

^ getting those brackets out is a pain-in-the-arse when you're an old fart working under a car on axle stands.  Firstly the road springs had to be removed to take the pressure off them, so driveshaft inner coupling and damper, then the spring could come out, and the trailing-arm pivot-bolts removed, and then finally the bolts holding the brackets to the chassis rail.  Thankfully the corner triangulation / gusset plates I had added didn't restrict access too much but still it was working blind to get the socket in there.

P1390660s.JPG.221d6b5d112243dcd6a6fbaabd1c3533.JPG      P1390659s.JPG.3d988d5a264d093c72ff3b90b6c34339.JPG

^  brackets off the RHS of the car.  The Left bracket with notch Up is type-1 and from the inside, and the right bracket with notches up is the type-2 (which I'm also indicating with the blue masking tape) and that was next to the sill.  on the table this was designated 2U-1U   

^^ RH piccie shows these reversed and inverted as suggested.  On the table above this designated ID-2D.   Nope., the angle didn't suddenly change as I stepped over them to take a photo from that side.  But as I say, I might have been missing something so I put the car's suspension back together again with the brackets this way around.

Then loaded the car up again and bounced, rocked and rolled it forward to the marked-level ground.  But I do admit that I haven't yet driven the car to re-settle the suspension, but for a quick check I presumed this might give us an indication.

Results ;  that side's wheel has adjusted, in part the suspension appears to have dropped by 10mm (wheel centre to wheel arch) which was much more than was predicted in the Buckeye report. This change is in part due to the pivot axis (although the same 2.08 degree angle) being of a different height (as illustrated below) relative to the chassis rail / the bolts on the brackets . . .

1489678292_Trailingarmbracketseffectoncamber4.thumb.jpg.ed5548d515a21f5e444d9c0c2f922773.jpg

^ Drawn to scale, the brackets -3.2mm (type-1 bracket) or +9.35mm (type-2 bracket) offset relative to the chassis rail / the mid axis of the bolts through those brackets.  

Top is how the car's RHS trailing arm brackets were. And across the bottom is how they now are.  And yes as I thought, the pivot's axis angle is unchanged (at 2.08 degrees) and the height relative to the bolt's horizontal axis is lower (by some 6mm).  According to the report this height change should have rotated the wheel, around the spring by " 10.5"/19" or 55% of the change in the bush axis height" ..which translates as lowering the ride height by 55% of 6mm = a little more than 3mm.   For whatever reason my quick check suggests its lowered by around 10mm.   And this is with the M&T supplied replacement road-spring fitted. 

The camber angle did not change by 0.6 degrees, as the table suggests (..so I've not yet gone completely nuts !) but it does appear to altered by almost 1/4 of a degree ..from 0.73 degree of positive camber to 0.51 of positive camber.  Because the angle between brackets has not changed - I might only attribute this change to ; 1. the camber changing according to suspension compression (ride height), and 2. because each of the bracket bolts have been pinched up but not tightened yet, so they have self adjusted with the bushes now being in line and also with any slight slack in the chassis or bracket's holes.

The looseness of fastenings, until the road-spring was refitted, probably also accounts for the noted change in ride height.

- - -

So that's about it.  I think to further correct the camber, I'll need to buy two more type-2 brackets, and to swap them out for the type-1's that are fitted.  This ought to alter the angle between the brackets by almost exactly 1 degree, which will translate through the geometry (according to that report) to -0.87 degree of the wheel.  That would take the present 0.51 deg positive to -0.36 (negative) camber ..which is exactly what I want.   However the ride height will go back up again be 3 or 4mm. 

I think only shorter / lowered springs, or less than 7mm thick collars, is going to help with that.  

 

P1390664s.JPG.15f6d999fcc2eace039bce86cb46e387.JPG

^ Interestingly, or not, from photos taken when I was first looking around under this car.., the brackets this way up (now inverted) are close to what we had before the chassis change. . . particularly evident with the inside bracket (top left in this photo) whose the bottom edge is almost parallel with the bottom of the adjacent chassis leg.

I'm particularly grateful to the gentlemen who wrote the article for Buckeye Triumph  as, although their data is in some parts wrong, they have provided a lot of useful measurements and an overall well-worthwhile insight into the geometry of these IRS components.  BIG THANK YOU to them. 

Pete.

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Similar Content

    • By Sheldon_Classic_Britian
      Hello Everyone
      So I thought I would make a topic about my YouTube channel and my cars and project. So for those who don't know 4 years ago I bought my first car a 1975 Rover P6 2.2SC manual and I made a video on the car and then I made another and another and it became popular ( God knows why LOL!) and people started subscribing and people really seamed to like what I was doing so I carried one and it never really stopped! So I created this topic to connect with some viewers and two see your cool projects and no it does not have to be a Rover! Mostly I just want to chat to people about there projects swap ideas and chat about cars and of course if you have a cool car that I could film that would be great =)  
      Thanks for looking and look forward to seeing your cool stuff! 

    • By 62 Austin
      I saw a TR7 F/S in EBAY only a 6 hour drive away.  Coupe. Doesn´t run. White. In the USA. The upholstery is Looking Out For Better Weather. $500 starting bid. I only dimly remember what´s wrong with these; besides torpedoing a whole company and the engine. Anyone ever drive or buy one? Export only, or did there used to be people in England, Scotland & Wales driving these around? This 1 has the Dorsal Escape Hatch.
      https://i.ebayimg.com/images/g/T4gAAOSwNWxZ7Rrh/s-l1600.jpg
      https://i.ebayimg.com/images/g/Rp0AAOSwWHBZ7Rrw/s-l1600.jpg
×
×
  • Create New...