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Just f**ked the engine


jevansio
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You know I'm starting to think sod all this built stuff, I originally only wanted a built engine for the "kudos", if I can get a good engine it could be a cheap fix, and if I'm only paying circa £800 I won't care how much abuse it gets, I think I'd pamper a £10k built stroker incase it went poop :D

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You know I'm starting to think sod all this built stuff, I originally only wanted a built engine for the "kudos", if I can get a good engine it could be a cheap fix, and if I'm only paying circa £800 I won't care how much abuse it gets, I think I'd pamper a £10k built stroker incase it went poop :D

 

Good way of looking at it, im trying to blow mine up so i can fit my new engine, the poxy thing wont give up:D

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Chris, the caps were loose but I have good confidence that when they were installed they would have been torqued upto the correct torque, the engine has been running for quite a while & survived TOTB & VMax

 

What reasons could the cap bolts loosen over time?

 

None other than never being torqued up in the first place. Even a warped head and out of line bearing bores shouldn't loosen them, just wear them badly and unvenly.

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None other than never being torqued up in the first place. Even a warped head and out of line bearing bores shouldn't loosen them, just wear them badly and unvenly.

You don't think if the exhaust manifold studs are pulling out the head the exhaust cam cap bolts could do the same?

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Not unless they were grossly overtightened. Exhaust studs only pull out with poor aftermarket manifolds that warp or elongate with no clearance in the stud holes and the wrong kind of gaskets, again, unless grossly overtightened. Note how the stock manifold is divided with an expansion / contraction bellows, at great cost? That's why it's there, a dirty great long piece of cast iron, or stainless plate expands at a very different rate to a cast alloy head. Something gives or warps without countermeasures.

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Having read through the thread since my last comment, I thought I'd post my hypothesis on a couple of things (I'm not hugely technically minded, so feel free to prove wrong, put straight, or tell to piss off :D )

 

1) Potential damage to block from snapped cam -: I'd imaging that most of the filings from the damaged cam will have been caught by the valve stem seals, so shouldn't have managed to make their way into the lower part of the engine. Though I accept that some of them could have gone down the gallerys into the sump, but to then have them picked up and spread round the engine by the oil pickup seems unlikely in my mind.

 

2) no compression on number 1 :- When a cam is tightened down, it has to be done in a sequence to make sure there is even pressure so it doesn't snap, so if a cam has snapped. Could it be feasible that the cam is now being held down over number 1 lower, as it snapped at number 6, therefore could it be holding the valve open slightly causing your low compression?

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Just found this :( Heard it referred to from other threads. Nasty business - the stock used motor is the best way to go because of exactly what you said - £800 and some spanner work, and relax. Why spend ten grand when you can get silly power with the stocker.

 

I hope you get it sorted soon, it sounds like there are heads/blocks available from the membership :thumbs:

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Just found this :( Heard it referred to from other threads. Nasty business - the stock used motor is the best way to go because of exactly what you said - £800 and some spanner work, and relax. Why spend ten grand when you can get silly power with the stocker.

 

I hope you get it sorted soon, it sounds like there are heads/blocks available from the membership :thumbs:

Cheers Ian, I'm converted, stock motor for me :D

 

Pulling bits off the head I can't believe how many orrifices have been helicoiled!!!!

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Any free time this week I've spent getting the head off. The Hodgemeister came over again today to lend a hand, with his help we finally got the head lifted off. I think John was quietly impressed with my mechanical skills, esp the way I could pretty much tackle most of the head removal with just a hammer :D

 

I don't really know what I'm looking for, but John had a look at the bores & pistons. In his opinion they looked fine (well good enough to make it worthwhile trying a head on & seeing what the compression was like).

 

attachment.php?attachmentid=105274&stc=1&d=1266079803

 

attachment.php?attachmentid=105275&stc=1&d=1266079803

 

We cleaned the piston tops up, there was no scoring of the bores & no marks on the pistons. The pistons did move ever so slightly, is this normal? Is this so that when everything is upto temp there's room for expansion.

 

We also stripped the head of the valvetrain, it wasn't something we needed to do but I thought it would be good experience for me.

 

So the current state is we think it's worth taking a risk on fitting a new head. Jamie has one he's prepared to let me buy & John has a set of JSpec cams he's given up for the cause :D.

 

We going to clean out the oil cooler lines, and a couple of oil changes initially, if all seems well I'll swp the 264's back in.

 

Could end up not being an extremely expensive mishap :)

IMG_4821.jpg

IMG_4822.jpg

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So the current state is we think it's worth taking a risk on fitting a new head. Jamie has one he's prepared to let me buy & John has a set of JSpec cams he's given up for the cause :D.

 

 

 

Mate the head i have is complete with cams, Lee checked it over and its spot on according to him.

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Mate the head i have is complete with cams, Lee checked it over and its spot on according to him.

You're a star mate, I was just waiting until the weekend was over to see if I really did need a new head (or full engine), now I know my plan I'll contact Lee about getting a courier down there, remember to PM me your bank details bud :thumbs:

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You're a star mate, I was just waiting until the weekend was over to see if I really did need a new head (or full engine), now I know my plan I'll contact Lee about getting a courier down there, remember to PM me your bank details bud :thumbs:

 

I was just about to order some oil, 2 cans of 15-50 mobile1 sound fair?:)

http://www.opieoils.co.uk/p-803-mobil-1-15w-50-advanced-performance-synthetic-engine-oil.aspx

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