UKKid35
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| posted on 22/8/15 at 10:27 PM |
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Where is this from?
I ask myself that quite frequently because I am trying to keep a TVR Cerbera on the road/track. So I am not in the same league as you guys, I'm
not trying to build anything, I just want to maintain my car.
There are several parts that I have tried to replace, some are available through TVR suppliers (with significant TVR Tax) and some are not
available.
Recently I have tried to find 12mm diameter cam cap dowels (10mm height, 8.5mm ID) and I eventually found that they used in Ford Duratec engines, but
I don't know the part number. Have you ever tried buying a part from Ford without a part number?
I would also like to know where these Solid Valve Lifters are from. They are 42mm diameter, 27mm height and weigh 74g.
I hope you will be patient with me if I return with more "Where's this from?" questions.
Thanks in anticipation
[Edited on 24/8/15 by UKKid35]
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coyoteboy
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| posted on 23/8/15 at 12:17 AM |
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Sorry I can't help on the part numbers but 74g per lifter?!! Jeeezo.
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rusty nuts
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| posted on 23/8/15 at 06:53 AM |
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In your position I would take the parts down to your local friendly engine reconditioned/machine shop .I know the guys at my local shop would be of
help.
Your photo of the lifter appears to big too large to view , might be worth reducing it and also put your location in your profile, someone local to
you may be able to help?
Welcome to the site, I hope we can help
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UKKid35
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| posted on 23/8/15 at 03:00 PM |
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quote:
Originally posted by coyoteboy
Sorry I can't help on the part numbers but 74g per lifter?!! Jeeezo.
Is that because it's heavy or light?
My only point of comparison is the much smaller hydraulic lifter from my other car which is 32V, rather than 16V eight cylinder, and it weighs 64g.
I guess the AJP8 lifter is also much larger because the cam is high lift (0.5" I think), but the biggest difference is that the hydraulic lifter
has over 150k miles on it and is perfectly polished, whereas the low mileage solid lifter is highly scored (in the oversize photo).
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coozer
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| posted on 23/8/15 at 03:45 PM |
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Dont be afraid to ask, we are here to help and we all love pics of everything!
Sorry cant help with ya Q but welcome along.
Some pics of your ride would be nice as well. Get them up!
Steve
1972 V8 Jago
1980 Z750
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Hodor
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| posted on 23/8/15 at 04:25 PM |
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quote:
Originally posted by coozer
Some pics of your ride would be nice as well. Get them up
Some pics of your car would be nice too 
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UKKid35
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| posted on 23/8/15 at 07:53 PM |
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quote:
Originally posted by Hodor
quote:
Originally posted by coozer
Some pics of your ride would be nice as well. Get them up
Some pics of your car would be nice too
OK if you insist
This is why my car is in pieces
And this is when I'm having fun
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coyoteboy
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| posted on 24/8/15 at 09:17 AM |
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Lovely car! What's the cause of the deformation?
Jeezo was for "wow that seems heavy for something that sits atop the valve spring - my 16v 4pot lifters seemed a lot lighter (I've
rebuilt it now, can't weigh them damnit).
Guess the car part and find it's source is a game we like playing here.
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UKKid35
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| posted on 24/8/15 at 12:56 PM |
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quote:
Originally posted by coyoteboy
Lovely car! What's the cause of the deformation?
I have a theory about the cause of Head Gasket Failure, but it's just a guess, I'd be interested to hear other suggestions.
Firstly my car does pink briefly if I'm not gentle with the throttle around 2k (due to an overly aggressive head skim). A remap got rid of most
of the pinking, but a little always remained, exacerbated by hot weather or traffic. I think this has probably weakened the HGs.
Secondly, I have run low on coolant several times for several different reasons. I had a rad leak and didn't realise. That was two years ago and
probably the worst overheat, because I didn't believe the temp gauge (I'd only recently had it repaired and I assumed it had gone wrong
again).
On another occasion my car dumped most of it's coolant through the expansion tank cap relief while in hideous traffic in Luxembourg. I think
that was due to the temp sensor under-reading, and therefore failing to switch on the fans (it would show only 70C while cruising using the diags).
Over the last couple of months it has simply being over-pressuring, and expelling coolant. I have replaced the temp sender, and thermostat, and
expansion tank cap, and each time the symptoms got a bit better. Probably because each had been damaged due to the system overheating. Each time I
hoped it had been cured, because I wouldn't loose much on a run, perhaps just a cup or two.
However, by the time I got to the Ring last month it was using a litre per hour. By the end of the second day it was using 2 litres a lap.
I didn't let that stop me have a brilliant time, because it was no different to drive, other than a little harder to start, presumably because
it was sucking coolant in to the cylinder when cooling.
This is not the first time I've taken the heads off, as the car was overheating when I bought it four years ago. I assumed the worst and
replaced the head gaskets, but there was no definite damage the to gaskets that I could see. Only when I replaced the radiator did the overheating
stop completely.
This time it is obvious that cylinder 2 has failed, and here are my (horrible) compression numbers from four years ago once I'd replaced the now
heavily skimmed heads.
1 235
3 225
5 235
7 260
2 255
4 260
6 245
8 245
So it is possible that pinking played a part, since it is one of the highest compression cylinders. Also this engine has some really very awkward head
nuts which require special tools to access. The failure is close to one of the highly recessed head nuts, and I had issues with the weld failing on
the tool I used (perhaps I didn't quite get the torque right). I also have an oil leak from around cylinder 1 where oil feeds the head, and
where one of the other very awkward nuts is. Also I've only just read that the threads should have Hypoid oil applied before torquing to spec,
and I don't remember doing that.
So perhaps the HGF is due to a combination of factors:
Incorrect head nut torque
High compression and pinking
Overheating
Track use
Pic shows recessed head nut
Pic shows even more awkward head nut, again with no line of sight
[Edited on 24/8/15 by UKKid35]
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coyoteboy
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| posted on 24/8/15 at 01:07 PM |
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Sounds logical, plenty of factors coming together there, but it looks more to me like 3 has failed taking out 1 and 5 with it! They are a bit all over
the place aren't they?
Those head nuts are horrendous! I can't believe anyone would design something like that, but I guess we don't see the other compromises
they would have had to make.
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UKKid35
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| posted on 24/8/15 at 06:07 PM |
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quote:
Originally posted by coyoteboy
Sounds logical, plenty of factors coming together there, but it looks more to me like 3 has failed taking out 1 and 5 with it! They are a bit all over
the place aren't they?
Those head nuts are horrendous! I can't believe anyone would design something like that, but I guess we don't see the other compromises
they would have had to make.
The engine ran for nearly four years and probably 20k miles after my first gasket change, so I don't think the compression spread was a
contributing factor to the HGF.
You might not believe this but the engine was less than 3% down on specified power after the remap, even with those compression numbers. So I
don't think cylinder 3 has been a problem, except it probably doesn't encourage smooth delivery. But these AJP8s are not renown for being
smooth; they are raw, scary and insanely addictive to drive.
Those head nuts are horrible, but like most things having the right tools makes all the difference. So I'm somewhat less concerned this time
round. But the design of this engine really is superb, you would not believe how small, light and powerful it is.
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