250 valve cover replacement

The o-ring is NOT designed to be replaced. There is a split in the top of it to enable the very careful removal of the cam and chain covers. Make sure you do not damage it as you remove the covers.

 

Dyke, I hope you won't mind my attempt to expand your answer a little ?

... or at least that's my experience with later (Tipo 251) engines with multiple (10) O-rings between the heads and timing chain case. I assume GTE engine has similar design (with less O-rings ?).

I recently corrected similar leaks on a Tipo 251 (Daytona) engine and discovered evidence suggesting not only of the leak(s) having been there already in '75, but likely since the car & the engine were built new ('72), i.e. manufacturing defects (??).

 

bob, you mean the rectangle ring between the cylinder head and the chaincover? this you only can change when you loosen the chain cover. but as DRW46 already has written: not designed for replacing.
the split at the top you put a little silicone seal between before you put on the cover, use a thin sheet metal, cut out a circle for the cam and put this metal in front of the rectangle ring, then put the valve cover on and remove the sheet metal.

 

Timo is correct, as is Brian in the other thread you started. If your original o-ring is damaged, you can carefully cut it off at the head/chaincase surface and cut a new o-ring to match. Use extra silicone sealant to seal the two pieces together and also in EVERY corner of the cam cover gasket where it contacts any mating surfaces. While you need a fair amount of sealant, don't use so much that it that the excess squeezes into the insides of the engine.

 

Damn auto-correct. Meant to say/write ...

 

There is also a step in the cam cover re-installation routine that is important to keeping the rubber seals in place. I'm referring to the temporary shim between the cam cover and sprocket cover. This is mentioned in the old manuals. If you are not familiar with it let us know and we'll oblige. Good luck.

john

 

It has been so long since I took the cam covers off my 330GT that I only remember the care needed to put them back using a thin brass sheet with a semicircle cut out.

I vaguely remember square-section "O"-rings around the entire timing cover. Are they square?

 

It has been so long since I took the cam covers off my 330GT that I only remember the care needed to put them back using a thin brass sheet with a semicircle cut out and something to make the rubber slippery.

I vaguely remember square-section "O"-rings around the entire timing cover. Are they square?

 

Get the green gaskets.

 

yes

this I mentioned already in my post no.5, but I have written rectangle. so sorry for the wrong word

 

I apologize. I somehow missed your post. It probably is rectangular. I don't remember.