Zel's Motoring Adventures...Volvo, Renault, Rover, Trabant, Invacar & A Sinclair C5 - Updated 13/11.

[PhilA]

3 hours ago, Zelandeth said:

Yeah, thankfully while I've not actually done much work on these engines, I have driven a fair few things with them - both well maintained and...otherwise.  So provided it's not knocking its arse out I'm not too worried.  We know it's not the original engine, so really haven't the slightest idea how many miles it has on it.

Yup. They'll go on and on and on and on. Even if they've got busted head gaskets and cracked liners and no oil pressure until about 1500 rpm.

If it's sitting somewhere just off the rest at idle, hot, and comes up to >5 psi by 1000 rpm generally you'll be fine.

Phil

[Zelandeth]

First time in...well we really haven't a clue I'm afraid!

Yes this is actually less than a mile from home, but feels like an important milestone.

Missfire is still stubbornly with us sadly.  Had hoped if it was something like a fouled valve seat that some revs with the engine under load might have cleared it.  We did blow a HUGE cloud of black crap out the exhaust on the first roundabout exit though!  Once the gasket set arrives (and it's less than 32C outside) we'll dig into properly investigating that in more detail.  There are a few things I can do to help narrow down if we're looking at a top or bottom end issue but it's just way, way too hot out there to do anything (including exist) right now.  So I've retreated into a dark, air conditioned room to do something else.  Which is annoying as there are a long list of things I'd rather be doing now - mostly relating to this car as it's the new toy.  Also want to get the Caddy properly valeted so I can get it up for sale.

Wheel alignment has been added to the "sort this sooner than later" as there is evidently waaaaaay too much toe out going on at the moment.  I'm not expecting the handling on this car to be anything other than seriously floaty, but it's currently a bit ridiculous.

[SiC]

Do you have an air compressor? Ideally a leak off test but even compressed air down the plug hole and listening intake/exhaust/dipstick tube should give some indication where all the compression is leaking to. 

[Zelandeth]

32 minutes ago, SiC said:

Do you have an air compressor? Ideally a leak off test but even compressed air down the plug hole and listening intake/exhaust/dipstick tube should give some indication where all the compression is leaking to. 

I do, and it probably wouldn't be too difficult to rig something up.  Though equally it was quick to dig in and take a look for anything obvious visually.  I think we might have found something - even though I abruptly realised that ignoring my prior decision to hide inside from the deadly laser that is the sun was foolish. 

Exhibit A.

Doing this between any other combination of valves reveals they're all sitting level...Except for the intake on number 5, which is sitting the best part of 1mm lower than all the others.  Coincidence?  Seems unlikely to me.

Also noted that there are no shims under the rocker pedestals.  Which if everything is standard (including the head gasket) and the head hasn't been skimmed should be fine apparently.  If the head has been skimmed or the metal rather than composite type head gasket has been used though, it may need to be considered.

Fact that we do have a valve sitting visibly lower than the rest is definitely an interesting development though.  Reckon the next step there is probably to pull the intake and see if something has been inhaled that we might be able to remove...Doubtful, but removing that is a major chunk of the work involved in pulling the head which will likely be the next big step anyway. 

[SiC]

A few good taps with a mallet to see if it'll loosen up a bit? Could be carbon build up and/or varnish on the stem from sitting that is sticking it open.

[Zelandeth]

7 minutes ago, SiC said:

A few good taps with a mallet to see if it'll loosen up a bit? Could be carbon build up and/or varnish on the stem from sitting that is sticking it open.

That will definitely be tried before I put everything back together.  I had to bail about 30 seconds after taking that photo so I could get the tools in the garage and door shut before passing out from heat exhaustion became a real threat.

Tend to think if it was just a bit sticky and was going to free off though it would have done so by now.

[SiC]

I wondered if it was sticking that it might return up sometimes but not always. The repeated hammering by the rocker might not give it enough time to get fully up again either and making it worse. Just a random ponder.

[Jenson Velcro]

Does the RV8 have hydraulic tappets? If so would they compress if a valve is sticking, rather than moving the valve fully.

Tapping them as SiC’s suggestion would then be more likely to free up a sticky valve 

[Zelandeth]

3 minutes ago, Jenson Velcro said:

Does the RV8 have hydraulic tappets? If so would they compress if a valve is sticking, rather than moving the valve fully.

Tapping them as SiC’s suggestion would then be more likely to free up a sticky valve 

Yes, and I imagine yes to a point.  I know the valves have been moving though as I've watched them with the engine running.  It just seems this one isn't seating quite fully.

It's possible that moving it further/with more energy than the rockers usually do may help jar something free, but I'm not holding my breath.

I have confirmed the pushrods are all straight as well at least, as one of those being bent (or someone having fitted the wrong one in one position) could cause all manner of fun and games.

[SiC]

Tbh I think it's likely a head off job. But if it could be freed and get compression even for a bit, then you have a good indication of the rest being sound.

[Zelandeth]

14 minutes ago, SiC said:

Tbh I think it's likely a head off job. But if it could be freed and get compression even for a bit, then you have a good indication of the rest being sound.

Aye.  Probably the biggest single step there (assuming the exhaust manifold bolts play ball...Big assumption) is removal of the inlet manifold, which is needed to have any hope of actually getting a look at our valve anyway.  Wouldn't be a bad thing to have the opportunity to have a proper look at what's been going on in that cylinder anyway - hopefully the liner hasn't been totally wiped out due to bore wash. 

We'll see I guess!  Can't really go digging too much further until the gasket set turns up.  I also need to go digging through the garage to see if I can find my valve spring compressor as I don't think I've seen that in about a decade, and at the very least I get the feeling that I'm going to wind up needing to remove and lap in a couple of valves.  Hopefully without launching one of the keepers into low earth orbit as happened last time I tried to remove one.

[Crackers]

6 hours ago, Zelandeth said:

I'm not expecting the handling on this car to be anything other than seriously floaty, but it's currently a bit ridiculous.

I think you'll be pleasantly surprised. A V8 P6 can cut a serious hustle down a good road. There's an almost Citroen-like quality to the balance of body roll and road-holding, I gave mine a proper leathering down some decent tarmac a couple of times and you can really get into a fantastic flow with it... And it still manages to be compliant, comfortable and smooth! 

[High Jetter]

1 hour ago, Crackers said:

I think you'll be pleasantly surprised. A V8 P6 can cut a serious hustle down a good road. There's an almost Citroen-like quality to the balance of body roll and road-holding, I gave mine a proper leathering down some decent tarmac a couple of times and you can really get into a fantastic flow with it... And it still manages to be compliant, comfortable and smooth! 

Yup, they were stunning. Drove our company Drs 'company' car PHC 99M a couple of times, it shifted!

[RichardK]

3 hours ago, Crackers said:

I think you'll be pleasantly surprised. A V8 P6 can cut a serious hustle down a good road. There's an almost Citroen-like quality to the balance of body roll and road-holding, I gave mine a proper leathering down some decent tarmac a couple of times and you can really get into a fantastic flow with it... And it still manages to be compliant, comfortable and smooth! 

When I had a manual 3500S in Kelso it was close enough to boy racer times that it got to work out a bit. In 2000 it was capable of upsetting one of the more confident ones in his XR4i, and I never held back on my driving style with it despite it being a decade older than most things.

Being white it also made drivers of a certain age visibly shit themselves when it appeared in the rear view mirror. "with a sense of purpose". Don't think I have driven another '70s car that was so easy to overtake everyone with.

The SD1 V8-S I considered to replace it felt decidedly gutless by comparison.

[Zelandeth]

Definitely think we have something stuck in the seat on no 5 intake.  When opening any of the others manually, they close with a nice sharp "clack" - whereas that one sounds decidedly dull when it stops.  Sadly the "whack it with a mallet a bunch of times" treatment didn't do anything.  Was worth a shot.  It was notable when I had the intake duct to the carbs of that you can definitely hear the miss as a really rather loud pulse through the intake - so I'm increasingly convinced that is where our problem lays.  Exactly what form that problem is in remains to be seen.  Next step will be to pull the intake manifold when the gasket set arrives - I'm not doing it until then as I don't want to immobilise the car for any longer than I can avoid.

Wonder how much I added to the value today by giving the interior a quick clean?  It wasn't really bad in terms of grime, but was really dusty and full of cobwebs.

Also noted while doing that job that the clock has completely at random decided to come back to life - I can't claim any credit for that, it just did it on its own.  I just noticed it was ticking again when I was cleaning things.

Given that the environment in a car is about the worst case scenario for a mechanical clock to exist in I'm quite surprised it's going again to be honest.

 

[SiC]

Possibly came back into life when it was driven and gave a few thumps into it, loosening up anything stuck when going over bumps?

[Jenson Velcro]

Have you got one of those micro inspection cameras on a flexy stalk? Either with its own screen or a usb connection to a laptop. You could have a quick look in the spark plug hole or down the inlet if you take a carb off if you do

[Zelandeth]

41 minutes ago, Jenson Velcro said:

Have you got one of those micro inspection cameras on a flexy stalk? Either with its own screen or a usb connection to a laptop. You could have a quick look in the spark plug hole or down the inlet if you take a carb off if you do

Sadly not. I keep thinking about buying one.

[High Jetter]

I got one velly cheep off the bay after a recommendation in PC Pro years ago, it works well on the rare occasions I've used it. Under a £10er

[Zelandeth]

Some parts have arrived.

Head gasket set and fuel pump rebuild kit.

Have established that the slightly worrying clacking from the top end at idle isn't actually worrying.  The pulse back through the intake from our duff valve was making the metering piston in the right hand carb bounce.  Refilling the dashpot has stopped it.

Probably be next week before I get a chance to start pulling things to bits as we've got family on holiday from work this week so have social obligations which are getting in the way of vanishing for hours to take cars to bits!

[Zelandeth]

Starting point today:

Ish.  That's a photo from a week or two back, but you get the idea.

Couple of hours and a small amount of swearing (mostly at the bracket the throttle linkage/kick down cable attach to) later...

Note that some of the intake manifold bolts are different, so keep them in the order they came out.

The choke cable end is really frayed so definitely wouldn't be going back into the linkage on the carb if I took it out, which is why the one carb is just tucked in the corner.  There's plenty of length of cable available to keep it out the way so I figured I'd just leave it alone rather than adding to my immediate to do list - though the cable does want changing longer term.

Can't really see anything useful looking down towards our offending valve.

At least not that I'm able to interpret.

It's not something obvious like a bit of rag having got sucked into the intake anyway, so the head will have to come off to investigate and resolve whatever is going on.

That will be the next step.  I'm not touching the exhaust manifold bolts, the join to the downpipe has clearly been apart relatively recently (the bolt is still shiny) so it will be getting split there.  

I was really quite surprised with how clean things were under the intake gasket/valley cover given that these engines don't exactly have a reputation for internal cleanliness.

Again kind of wishing I knew better what the story of this car was.  I almost wonder looking at this whether this engine has had at least some rebuild work done (the water pump and timing cover gaskets externally look bright enough to be essentially new), and it then just sat around for a long time before developing this problem when fired up eventually.  I did note when it was running that there was very little apparent blow by.

Nothing really found yet, aside from a surprisingly clean looking engine anyway.  We'll know more when the head comes off.

[Zelandeth]

Literally only had 15 minutes for it today, but was determined to make some progress however small.

Rocker shaft and push rods removed.  I also pulled three cam followers at random for inspection.  They all look like this.

The mark around six o'clock is a fingerprint, not surface damage.  Feels completely smooth to the touch.

Next I need to remove this engine steady...

Which I note is already missing a bolt.  The equivalent bracket at the rear is what the throttle linkage and kick down cables fasten on to, it can stay where it is as everything else is already detached from it.  Which caused much swearing as I had to unscrew the adjuster for said kickdown cable and the adjuster was seized.

Then either split the downpipe or exhaust manifold.

I was leaning more towards the downpipe, but I'm now second guessing myself.  I can see that join being a git to re-seal afterwards, and from the looks of the gasket, the manifold has seen about as much service since the engine was apart as the innards suggest, so I may end up pulling the manifold instead.  Aside from anything else, I have new gaskets for that I don't for the downpipe... manifold is several orders of magnitude less annoying to get to anyway.

Elsewhere, apparently I do have at least one water ingress issue to trace.

I really hope that's not a sign of rot in the screen surround hidden under the chrome covers...

 

[Zelandeth]

Off with its head!

Nothing immediately obvious like a seat hanging half out the head, though I'm going to do a leak down test on all of these later today to see how well (or not) the rest are sealing.  

Can't pull the valve yet because I realised that I lent my valve spring compressor to someone about 15 years ago and never saw it again.  Have one arriving tomorrow.

Here's a closer look at number 5.

Then it's neighbour number 7 which I know was firing just fine.

It does look like the intake valve on 5 isn't seated quite as deeply as on 7.  We'll get a better look when I pull the valve.

There's a bit of tarnishing in the cylinder, but I've seen (and run) worse.

I am slightly suspicious as to whether this gasket had sealed properly.

Especially around here.

I note it has what appears to be a 2019 date code.  

Which if it is indeed a date code suggests someone has been in here relatively recently.  Which probably explains why the exhaust manifold just unbolted without any hint of protest.

Speaking of gaskets, there will be a slight delay before things go back together (obviously investigation of my issue and cleaning will take a bit of time anyway).  Spot the deliberate mistake.

Yeah... someone managed to order gaskets for a two rather than three row head...despite checking three times.  I do despair at my mental capacity sometimes.

[LightBulbFun]

18 minutes ago, Zelandeth said:

Yeah... someone managed to order gaskets for a two rather than three row head...despite checking three times.  I do despair at my mental capacity sometimes.

before you blame yourself, are you sure someone did not stock pick the wrong part? I mean from what I have heard about certain online parts suppliers on here, theres a good chance you might of just ended up with the Starter motor for an ALX400  

 

[Zelandeth]

13 minutes ago, LightBulbFun said:

before you blame yourself, are you sure someone did not stock pick the wrong part? I mean from what I have heard about certain online parts suppliers on here, theres a good chance you might of just ended up with the Starter motor for an ALX400  

 

Nope, this was definitely me.  I know I had both options open while I was determining which one I needed...best guess I just closed the wrong damned tab!  That's what I get for ordering stuff while tired.

[High Jetter]

6 hours ago, Zelandeth said:

Then it's neighbour number 7 which I know was firing just fine.

It does look like the intake valve on 5 isn't seated quite as

Y tho?

[SiC]

Probably worth putting Petrol (or water) on the top of that head and see if it leaks through the valves.

[SiC]

Might get lucky in just a pulling, cleaning of the valve and regrinding in may fix it if it's not sealing.

[Zelandeth]

Leak test actually didn't reveal much.  Which made me even more suspicious.  

There is always some pressure against the valves because of the spring in the hydraulic tappets providing some pre load.  So it's possible that if a valve wasn't seating 100% with that bit of pressure present, it might be without it - if for instance we had a slightly bent valve or something like that working against us.

With the valves pulled from number 5, no signs of damage to the seats at least.  Things have just had a really quick wipe down with a rag here.

Inlet.

Exhaust.

A lot of crusty carbon build up around the exhaust valve seat, and the valve looked correspondingly manky.

Intake valve didn't look too bad.

Of course today is the day I've run out of brake clean isn't it...

Rolling both valves on a flat surface I couldn't see any visible wobble of the heads, so if there is anything amiss with them in terms of being bent it's really subtle.

After only a few seconds of lapping the intake was looking way better.

Exhaust however (after I chipped a few of the really big crusty bits off before we started) is proving more of a challenge - there are a couple of pretty substantial pits which span the whole width of the contact patch.

After a little while I noted that it looks like when spinning the valve in the head that the valve head on this one is rotating a *tiny* fraction off concentric...so maybe the stem is slightly bent.

It's barely, barely visible...but my understanding on things like this is that it's perfect or it's not pretty much.  Sadly I don't have the equipment to really measure the run out and see if it's just the outer part of the head that's off rather than the actual sealing surface...but for the sake of £8 I'm tending towards just replacing it as a precaution.  If there's any suggestion that the valve may have been subject to trauma I'd rather just change it than have the head drop off in 500 miles and write off the piston and cylinder liner...which would cost far more than £8 to sort.

Obviously I'll need to inspect the others here to ensure there are no other valves with issues.  Cue potential for things to snowball...do I just replace them all out of an abundance of caution?  I'm already leaning towards pulling the other head given the potential evidence of this side having had things poorly prepped before fitting and possibly not been properly torqued down.  Suddenly that's another £150 worth of valves added to the bill!

Slightly surprised to see no evidence of any meaningful sort of valve stem oil seals fitted...there is an O-ring on each of the inlet valves...

...However I can't see them doing much given they're just sitting on the valve stem...most sitting up next to the top spring retainer.

A couple are sitting down on the actual valve guide too, but they're apparently just floating around on the valve stem.  That to me just doesn't seem right.  Granted, I don't know these engines well...but it doesn't seem right.

[SiC]

I've got a feeling that's normal? No expert but I thought they were to stop oil from the rockers running down the valve stem shaft and into the engine. I know you get top hat ones and they sit further down. 

@PhilA would be my go-to expert to ask on such matters!

Any leaking in the cylinder? (I.e. rings)

I presume the bore still looks good with no scoring?