Project 1974 MGB GT - The Mustard (Mit) Mobility Scooter - 6yrs ownership & the end is potentially nigh!

[MarvinsMom]

well at least it wasn't just us who used ALOT of oil getting too and from Gaydon at the weekend!

i checked the mini on monday morning and tht oil was very low on the dipstick, it took a litre or so to bring it back to where it should have been.....

and that is inspite of us checking it before leaving home, while there and on the way there and back.

the car does, we know use oil. it doesn't drip it, but it does use it. there are no clouds of blue smoke on start up and the like, but the oil is going somewhere! when we got the cylinder head done, we were told to keep on topping it up which we have done, but its not settling down. which i hoped it would. there is something amiss with it, and lets face it, an old a-series there would be no surprise if it is worn. saying that the car does start easily, and there are no clouds of clagg either when it does.

thing is i didn't enjoy taking the car to Gaydon. not one bit, been on the motorway was not something i want to repeat in that car. now we have used the Rover Mini on the motorway and i didn't feel any where as vulnerable in that as i did in the 1000. so much so i think, well, am now certain that i'm going to move the 1000 on. maybe to get something else which is more at home on a long run, or not, depending on what ever i see for sale......

[SiC]

It ain't happening yet, but I've been pricing up rebuild options...

Fast road @ 1860cc:
Ivor Searle - £2388
Oselli - £2950
Peter Burgess - £3240

If I go stock rebuild:
Ivor Searle - £1578
Oselli - £2150
(Peter Burgess price is unknown)

Could also use a local engine builder if going stock too. However I can't imagine it'll be too much difference from Ivor Searle price.

Problem is, I've already looking at getting something else and those prices for a fast road engine would mean that couldn't happen. Hmm.

But then a rebuild will be waiting till next year anyway.

[SiC]

thing is i didn't enjoy taking the car to Gaydon. not one bit, been on the motorway was not something i want to repeat in that car. now we have used the Rover Mini on the motorway and i didn't feel any where as vulnerable in that as i did in the 1000. so much so i think, well, am now certain that i'm going to move the 1000 on. maybe to get something else which is more at home on a long run, or not, depending on what ever i see for sale......

 

The MGB does do motorway reasonably well. Can hold 70mph comfortably and there is still power left in there to accelerate faster. Except you start getting disconcerting steering wheel vibration going above that. However at those speeds it's getting pretty noisy and drony through the exhaust.

 

It's much more comfortable on A-roads at 60mph though. Much more fun and enjoyable too.

 

We took the back roads on the way back from Gaydon. Two hours instead of one motorway, but it didn't feel like it in comparison!

 

I guess it's the era that these cars were designed in.

[richardmorris]

20 hours ago, LightBulbFun said:

I think he was just referring that doing one in general/when you pull the plugs next time would not be a bad idea and should not be much of a hassle especially if your already pulling the plugs 

 

I dont think He was referring to what you have fitted so far, but just referring to your general intention of fitting an electronic ignition setup and that he thinks it would not be such a great idea on such a car, 

I will say you might want to retract that second section, if you knew what his Day Job (and hobbies) entailed

 

it will at least give you an idea on whats gone wrong exactly and where to start when it does come to fixing the issue

and as such even if you cant do anything right now, you will have time to think with it and plan with it

 

I just noticed things getting a bit personal/hostile so just hoping to pacify things a little  (I do worry that genuine proper advice might be blown aside just because of the person its coming from)

Just reading this thread, perhaps he just has an aggressive tone of writing. Because it wasn’t coming across as gentle help ( like Ken Hanna in 2CVGB) but a quite angry: do as I say or you’re an idiot. All car clubs have them. I have one guy writing to me  ( in green pen almost)  in the CCC who is the same. 

[Mally]

If you are moving it on just leave the engine alone, it will run forever at the mileage you do.

When my oil burning resulted in clouds of smoke I just took the head and sump off, changed the piston rings (mostly broken), changed crank bearings that you can get to, for a total cost of around £100.

Drove perfectly for 12 moths then I sold it.

[SiC]

After a two month or so secondment to my father in law, she's back again. He's been running around in it, giving it some use and having fun. Not as many miles clocked up as I hoped, but probably about 300 or so since I left it with him.


Drive back was successful and I pretty much fully trust her now.

She did start playing games with her fuel gauge though. My FiL filled it up before he gave the keys back, but it's quite hard to get a full tank on this with modern vapour recovery petrol pump nozzles. When I left, the gauge was reading the notch under full (not quite three quarters, more 4/5ths) and was steady. Thirty miles in, I noticed the gauge was dropping down to half and going quicker as I put the miles on. 35 miles in, it was at the quarter mark.

I pulled over concern that I had a leak somewhere. Fuel pump looked dry, so I popped the bonnet to check stuff under there. Fuel filter attached, pipework all good. Feeling the carb overflow ports found them to be dry.

Decided nothing was obviously seriously amiss I decided to motor on. As I carried on, the gauge decided to creep just under half. This was reassuring but still a lot lower than it should have been.

A few miles on it dropped again and as I was passing a Sainsbury's, I pulled in to fill up with some cheap Super Unleaded. First click put in 12 quid, so I did the usual pull the nozzle out slightly while peering down the spout and put another gallon in. This fill-up would tally with the fourty or so mile journey since the last fill up.

Starting up and pulling away the gauge rose again. This time to just over half. Another few miles and it was back to full. Down the road some more, back to half...

I can safely say that the gauge is not playing ball. Its got a new (decent) solid state regulator powering it (need to double check it's output voltage to be sure though) and the sender is relatively new too. I have recalibrates the gauge, so that should be in a rough ball park. Since I did all that, it was fine until now. Irritating.

I'll have a look at it soon, but for now I'll just go back to filling up after 200 miles or so on the trip counter.

Back safely home, I did a few under bonnet checks. Brake fluid level fine, clutch fluid fine ... but this cap seems very loose...

Bugger.


I don't think I can blame bad manufacturing of the cap here, as I reckon I may have kack handily overtightened it previously. Then the hot weather caused it to compress some more until it split.

Thankfully I don't throw anything away. So I had a spare with appropriate patina on.


Does the job.


Next up was the oil level. When my FiL drove it, it hasn't dropped a smidgen from just over max. After I checked it from my drive, it had dropped down to half.

I think I know what the problem is here! My driving...

Admittedly I only had it stopped running about five minutes previously. I need to do a recheck now it's been sitting for a while. Oil should drop down relatively rapidly, but it still may take a bit of time.

One thing I have done is cleaned out the old filler cap and fitted it back on with the o-ring off the new one. The new one was very loose in the cover and the old one with its old o-ring wasn't much tighter. However the new combination of old cap and new o-ring made a very tight and snug fit.

I'm hoping/wondering this may help with the oil consumption. With greater vacuum in the rocker cover on overrun, it should hopefully prevent too much oil getting sucked by the rings. That is if the rings are what at fault.

Now it's home, I can give a compression test and leakdown test to check the general health of the engine. It's not going to be changed out anytime soon (Dolomite needs to get back on the road first), but it does allow me to plan what needs work next on the fleet and where the priorities lie.

I'm also intregeued to see what state a 158k mile 70s engine is in. Especially as it still pulling pretty well.

[dozeydustman]

10 hours ago, SiC said:

She did start playing games with her fuel gauge though. My FiL filled it up before he gave the keys back, but it's quite hard to get a full tank on this with modern vapour recovery petrol pump nozzles. When I left, the gauge was reading the notch under full (not quite three quarters, more 4/5ths) and was steady. Thirty miles in, I noticed the gauge was dropping down to half and going quicker as I put the miles on. 35 miles in, it was at the quarter mark.

I pulled over concern that I had a leak somewhere. Fuel pump looked dry, so I popped the bonnet to check stuff under there. Fuel filter attached, pipework all good. Feeling the carb overflow ports found them to be dry.

Decided nothing was obviously seriously amiss I decided to motor on. As I carried on, the gauge decided to creep just under half. This was reassuring but still a lot lower than it should have been.

A few miles on it dropped again and as I was passing a Sainsbury's, I pulled in to fill up with some cheap Super Unleaded. First click put in 12 quid, so I did the usual pull the nozzle out slightly while peering down the spout and put another gallon in. This fill-up would tally with the fourty or so mile journey since the last fill up.

Starting up and pulling away the gauge rose again. This time to just over half. Another few miles and it was back to full. Down the road some more, back to half...

I can safely say that the gauge is not playing ball. Its got a new (decent) solid state regulator powering it (need to double check it's output voltage to be sure though) and the sender is relatively new too. I have recalibrates the gauge, so that should be in a rough ball park. Since I did all that, it was fine until now. Irritating.

The ones on my scimitars did exactly the same as that; gauge would vary throughout the day, even on a long drive on a straight level road the needle would be up and down like an old whore's drawers all journey. Even a replacement sender and known good second hand gauge didn't do much to improve things so don't rule out the new sender being a bit iffy or the wiring between the sender and gauge being perfect. I wouldn't worry about it too much, you've got a "safe" mileage limit.

 

It's on of them things old cars do.

[SiC]

So I took the day off to recover from my bike injury. Really wanted to get on with a bit of welding on the Sprint, however I can't face lying on my side right now.

Decided instead to do a compression test on the MGB. I have done one before, not long after I bought it, however that was on a cheapy Chinese red box special gauge. This time I've gone and bought a Gunson unit. Not going to be calibrated precise but should be a bit better built.

Anyway enough waffle, here are the results:

Quote

Dry

Cyl 1 - 170psi

Cyl 2 - 165psi

Cyl 3 - 169psi

Cyl 4 - 169psi

 

Wet

Cyl 1 - 198psi

Cyl 2 - 196psi

Cyl 3 - 195psi

Cyl 4 - 195psi

What does the HBoL reckon it should be?

A few pictures ...to show I'm not lieing!

Cylinder 4 Dry

Cylinder 2 Wet

As you can see, it isn't that easy to read to a single unit precision on this gauge. Is that last picture 196, 197 or 198psi? Who cares to be honest - the gauge is not likely that accurate.

I'm rather chuffed with this result. Explains why the car pulls so well. This is a good engine. Not too shabby for an engine with 158.6k on the clock.

It doesn't help explain where my oil is going though. I would do a leakdown test now, however I can't because of technical issues (can't find it).

[Mally]

Leakdown gives you an indication of why you have low compression.

But your compressions are not low, so no point doing leakdown test.

You could still have a broken oil ring, but it's unlikely.  

 

[vulgalour]

Valve stem seals?  Princess used to use loads more oil before I did those, it wasn't until I was being followed by a friend that I learned it used to cough out a puff of oil smoke on every gear change, new valve stem seals stopped that and reduced oil consumption to tolerable levels.

[richardmorris]

Can you drive it in the dark and see if a smoke cloud shows up in the following cars headlamps? Compression seems as good as you’re going to get, so I doubt it’s oil rings. I’d go with vulgalour about valve  stems. Is it an unleaded head conversion or do you run it with an additive?

[SiC]

1 hour ago, richardmorris said:

Is it an unleaded head conversion or do you run it with an additive?

Neither! 

First owner owned it till 2002 or so. Second owner used it for a year or two and then got put away. Third owner recommissioned and sold it a couple months later. So first owner did the vast majority of the miles in it - probably good 150k. Given the dates, lead and LRP would have been common place. Thus it should have loads of lead memory. 

Given the tappy nature of the top end, I strongly suspect it hasn't had hardened insert put in. But then there it a cracked washer at the top of cyl 4 back valve. So likely someone has been in there before with a valve compressor - unless it was damaged out of the factory. First owner was apparently a mechanic & garage owner though, so I'd thought he would have got it sorted on warranty if was out the factory like that. 

Previous owner gave me lead additive. I have used it on the odd occasion but certainly not every tankful. 

I suspect it could well be valve stems too or rear main seal. Especially as there is engine oil dripping from the bottom of the clutch bellhousing area.

Pretty certain it only looses it if you thrash the engine and rev over ~4k. 

[SiC]

You can't see smoke when looking out the back. Neither from hard acceleration or overrun. 

@purplebargeken was following me on the way back from FoTU. To see if it was burning oil, I gave it an occasional thrash as he would possibly clearly see. 

Apparently it does give a few good smoke clouds. Bad enough to make his eyes water. Sorry mate!

[SiC]

2 hours ago, Mally said:

Leakdown gives you an indication of why you have low compression.

But your compressions are not low, so no point doing leakdown test.

You could still have a broken oil ring, but it's unlikely.  

 

New toy, wanted to play with it! Only a cheap red box one so not optimistic about its accuracy. (Why do I keep buying these crappy gauges and then regretting it)

However I was hoping to connect it up and see if I could hear where it was leaking out of. Top end or bottom end. 

Thinking about it, it's unlikely to tell me if the valve stems are leaking though? So not a whole lot of use in this instance. 

[1970mgb]

Compression is excellent both in terms of absolute numbers and cylinder-to-cylinder variation, and right where I'd expect an 18V HC engine to be.

 

A wet test will always be higher. Even though its ~25% higher, I'm use to worn rings showing a 50% or better increase on a wet test-i.e. a cylinder that's at 100 psi might jump up to 150 psi.

 

So, I'd say based on this, your rings are good and your valves are good. As others have said, even though leakdown does theoretically tell you more, I'm not sure what it could tell you in this circumstance. It's worth doing if your compression is low(to find where you're losing compression), but 170 psi on a B series engine is anything but.

 

Valve stem seals are a reasonable avenue to look at for oil consumption, as someone else mentioned. I run the "Umbrella" type seals. Somewhere or another on my desk, I have a note with a NAPA part number where I was on the phone with John Twist and he spouted it off from the top of his head, but I don't know how easy it would be to find(it's probably easier for me to call him again today and ask if you want me to), although I don't know how much use a NAPA p/n would be in the UK. I wouldn't necessarily want to change valve stem steals with the head on the engine, though. If it's off, it's easy. With the head on, you can do some gymnastics to do it, but it takes fast work and you'll probably end up dropping a valve and having to pull the head anyway.

 

I'll also mention that I recently took care of some serious oil consumption on my car by doing a lot of work on a parts box oil-air separator. Even though both the one on my car and the one in the parts box blew clear, the mesh was pretty well choked up on the one I cleaned up. I actually boiled it in solvent a few times, along with some other chemical concoctions to clean it up. I was surprised at how much junk came out of an apparently "clean" one.

[somewhatfoolish]

Stem seals can be swapped without tears or head removal; a short length of cheapo polypropylene rope fed through the plughole and the piston wound up to as near TDC as possible, then away you go.

[SiC]

The tappet chest is bit of a bugger to get without removing manifolds. I'd be surprised if it was that as I can easily blow through the pipe without too much restriction.

I can get the umbrella style valve easily on a lunch break from Moss Motors. Seem to have reasonably good reviews on the forums.

However it doesn't get over the fact it's tappy on the top end. If I'm changing valve stems, I'd rather send it off to Peter Burgess and get him to put hardened valve seats plus smooth out the ports. Rebuild and econotune (minor port polishing) is only £390. Bog standard hardened valves with him is only £235 too.

It won't solve the problem with oil consumption if it's the rear main seal though. I'm beginning to think it's that. Especially as I'd expect clouds or even visible smoke to the driver on overrun and acceleration. I've tried hard to cause it but I've yet to see anything visibly out the back.

Depending how quickly the Dolomite project goes over the winter, I hopefully will get tinkering time with the MGB. If so, I'll pull the engine and get a mild rebuild. As I know it's got good compression, I'm not intending to have it rebored (unless otherwise). Hopefully it will be perfectly fine with new rings and original pistons. Bottom end checked and bearings replaced. New oil pump. Then have the top end send off.

I've gone off the idea of having it bored out for more power. I think it's original numbers and I'm happy with the power it's giving. Boring out will mean more stress on the engine and likely more rebuilds over its life. 

[SiC]

This morning I did a quick check over on the ignition side as it's been a bit jerky.

Points had did this. Not sure why it's done this.


I set them back in place, reset the gap and retimed.

Also nicked some fuel out of the Dolomite... Better than it going off!



Then went off for a little 120 mile drive across the Wiltshire countryside to see a big steam engine in a building. A trip where the type of roads that this car was born in and exactly for. Even if the 29C weather gets a bit sticky in a GT. Temperature gauge was rock solid steady the whole time. Including sitting at traffic lights in the sun. Nowt wrong with stock MGB cooling systems with a mechanical fan.

Crofton Beam Engine




I've seen it once before in steam and it's good to be back. This exact area and countryside is where I grew up in. So have very fond memories buzzing around. I hoped to go Milton Windmill and Avebury, but Mrs SiC wasn't feeling too well so decided to just enjoy the drive.

A video of it in action as it was steam day today

The engine basically pumps up water for the Kennet and Avon canal. Nowadays it's done by an electric pump but on bank holidays they fire up the engine and take over for a bit. Unfortunately someone had managed to damage a lock further down and so their reservoir was getting very low. So they had to shut down near the end of the day. No doubt some holiday makers will be annoyed that they can't carry on up the canal.

Drive back had the car being juddery again. It's not awful but it's noticeable. Basically (unsurprisingly) feels like timing is out. Enough for me to know it's out of place. Points had did this again


Reset them a couple of times on a journey but they quickly went out of place. At least it's running I suppose. I imagine that's only because I have an electronic points assisted box attached.

I hate points.

[richardthestag]

where did the points come from looks like the spring is on da piss.

and that lass with the legs on the picnic bench distracted me

[SiC]

From here and these ones:

https://www.moss-europe.co.uk/points-set-contact-breakers-high-quality-gcs107hq.html?assoc=536599

I think they're Distributor Doctor. 

[SiC]

Looking at the picture at them close up, it looks like there is a rivet on the bottom. I wonder if the foot can be twisted a touch on that rivet. 

[somewhatfoolish]

There should be a circlip to stop the contact arm trying to come off the pivot.

[SiC]

That would make sense and something I have considered putting a starlock on to hold it. But I've not seen a circlip mentioned on 25d parts diagrams. The points I have used before I think have been the one piece design versions. This time I went for the expensive "high quality" one in the hope it'd last longer, wear less and work better!

I need to check if there is a bit in the post for the circlip to fit onto. I don't remember seeing one. Could always use a starlock washer too. 

[richardthestag]

1 hour ago, SiC said:

From here and these ones:

https://www.moss-europe.co.uk/points-set-contact-breakers-high-quality-gcs107hq.html?assoc=536599

I think they're Distributor Doctor. 

phone disti doctor up and ask him?

I am thinking not.  looks like a manufacture defect

[SiC]

1 hour ago, richardthestag said:

phone disti doctor up and ask him?

I am thinking not.  looks like a manufacture defect

I'll take it out and have a look first. If not, I'll try finding the receipt and take it back to Moss. 

Need to sort out the CSI ignition distributor I've got and have it changed to one without the immobiliser function. Then I can get rid of the points entirely - something the whole automotive car industry was quick to do all over their models, once the semiconductor industry got their processes properly nailed down. 

[SiC]

So I tried all manner of washer combinations on the terminal end and also tried moving the spring arm at extreme angles. However it still keeps riding up.



I think it could be one of two things. Either the arm isn't flat at the end.


There is a angle to the cam section too which maybe causing it to ride up.

My solution? I've put a set of cheap, one piece points on. These have a flattened end where the point moves on. Thus it can't ride up.

Like this but more plasticky and cheaply made. I think I paid under 2 quid at a show for mine. Moss are £3.50 and their cheapest ones.


However I'm not overly bothered about the quality as it's still running on a points assistance unit. Contact wear won't be a problem. I just need to keep an eye on wear and make sure it doesn't have too much slop.

Now tomorrow is the big moment for the car. It's going for its MOT!

In preparation I give it a quick wash and had a quick check over the car. I like to present cars for MOT that are clean and tidy, gives a good attitude to the tester - even though I know them pretty well now. Who likes to climb around and under filthy cars?

First off, even though it's not an MOT requirement, I decided to fix the flash-to-pass.

This requires removing the steering cowl.


Four screws and it's off! Compared to moderns, it's laughably easy.


Two screws to remove the stalk. Oh, that wire...


Yeah I'm not fixing that yet. It needs to come off, re-strip the wire and try to re-crimp. Or possibly solder but my soldering irons are in storage still, ready for moving.

So carried on with its checks. Everything seems good. Finally a quick test drive to clean the brakes and just give a good blast.

By this point it was dark, so I turned the lights on.


FFS! It broke and fell apart.


After some fiddling I got it all back together.


I didn't push the switch all the way back in, just in case it decides to break itself again. Thankfully and handily in this case, my local Moss branch in Bristol has moved literally around the corner from the garage that does all my work. So any problems, I can get them to buy whatever they need to fix it. Actually closer to them than all the motor-factors like Euro Car Parts and the like!

So I'm keeping my fingers crossed it'll pass. Going in first thing but could be at any point tomorrow that it's actually tested.

[somewhatfoolish]

Given the premium Diz Dr charge I'd hope for better; a starlock would do, but a circlip is the 'right' answer. Give them a phone and an opportunity to fix the fault.

[1970mgb]

Glad I never bought Distributor Doctor points. The price turns me off, but seeing the quality scares me. You're probably better off with the Moss or other supplier points.

As for the headlight switch-the new ones from Moss and the other suppliers all come from the same Chinese source, and they're all universally crap. You're lucky to get a year out of one if you use the lights with some frequency, which seems to be about the lifetime of most current production green box Lucas stuff. When mine went out earlier this year, I hunted down a new old stock red box Lucas replacement. It cost me about $50, but was worth every penny(one of these days, I'll get around to putting relays on my headlights, which not only makes them brighter but also saves the switch-I was surprised to find relays from the factory on the Marina).

[SiC]

Woo passed its MOT! No advisories too. 

I'm hoping that the switch was just a fluke and it has been slowly falling apart for a while. At the moment my lights are driven directly through the switch and no doubt contributes to my lights being like candles. I have a harness to convert to relay switched but yet to put it on - just kept to daytime/city driving in dark for now so not been an issue. 

Usually when I've been to autojumbles there has been boxes full of second hand switches. So if it breaks I can readily get a old replacement. Either way, if I drive it through a relay, a new repro or old original switch won't be too stressed.

I just don't like the tactile feel of the new repro switch gear. Especially the stalks don't click anywhere near as nice. Hence I'll re-crimp the broken wire on my original stalk rather than replacing with new. 

Other option will be to swap with the nearly new original Lucas switch that is used on the map reading light. I think the first owner must have fitted that back in the day, so will be an original rocker switch that has barely any current switched through it. 

[SiC]

12 hours ago, somewhatfoolish said:

Given the premium Diz Dr charge I'd hope for better; a starlock would do, but a circlip is the 'right' answer. Give them a phone and an opportunity to fix the fault.

I did check on the points base and there appears to be no groove in which a circlip could fit.