Cosworth BOA question..

[CTE]

I do not know if anyone can help, but for the first time I can hear the timing chain ratling under the front cover, at idle, it goes quiet when the revs go above 1000 rpm or so.. I have read past posts saying beware of the timing chain tensioner, and if you hear bad noises from the front of the engine, best get it changed (the engine came from a good home with 89,000 miles, but I do not have any records as to when the tensioner was last replaced).....which seems like a pretty reasonable idea compared with changing the complete engine, no matter how cheap they may be. The engine has run sweatly for nearly 3 years now, although I have only done 15000 miles or so, and have changed oil etc correctly.
Does anyone have any advice on this....I read a post once where it described how to change the tensioner without having to strip the whole of the front of the engine? Does anyone know of a garage who can do this competantly? I have not got the time or the interest to do this myself. The engine is in a TVR S.

Thanks

Mark

[phumy]

Do you mean the old BDA engine?

[CTE]

No nothing that exotic....I mean the V6 lump from a Scorpio 24V Cosworth.

[Boosted LS1]

The tensioner is held to the block by a single bolt so it needs a light tap to remove it. Once you take it apart you'll see how to lock it in a compressed state prior refitment. If it's knackered then it'll be in pieces so you'll know.

When you fit a tensioner, use some sealent on the gasket and some thread lock on the plug giving access to the allen key which locks/unlocks the tensioner. If you need help send me an email or feel free to call.

Oh, It's on the drivers side of the block. Have you got newish oil in there or could it be thinned old oil?

If it's not the tensioner then it could be the blade or the sleeve on the blade. Sleeves are known to break off or wear as time passes. Then the chain rubs directly onto the blade which is aluminium. You would hear that noise prior to oil being splashed onto the chain and blade.

Removing the timing cover is a pain as the sump has to be removed first.

[CTE]

Thanks Mike, I`ll try the oil first. It is a while since it was last changed, but I have done relatively few miles. I take it the timing cover has to come off to get to the tensioner?

[Boosted LS1]

^ No, the tensioner is on the side of the head. You can leave the timing cover alone. The tensioner is a small cast iron object the length of your thumb bolted to the head in front of the exhaust port for the front cylinder.

I'd try an oil change first, if that fails consider the tensioner. If that's ok the timing cover may need removing. It all depends on how bad the noise is and a good diagnosis.