My 88 cab developed an oil leak after I reinstalled the engine for a clutch. Before which, it never leaked anything. While the engine was out I replaced the oil pressure sender (pass side front of engine) I reinstalled and it leaked from that general area. ARRRRGGG!! The car also developed a random miss. I thought it was bad gas, the injectors, plugs, bad wire etc..... nothing fixed it. I got sick of the oil leak and replaced the sender with another one, it still leaked from that general area. Well, low and behold it was not the sender, it was the on engine thermostat O-ring. Who'd a guessed???? I removed it (pain in the @$$) $1.30 o-ring solved the leak and the resulting vacuum leak (the miss) all in one!! Gotta love that. The old O-ring was beyond brittle and shrunken.

The miss was the same as when you have the engine running and you remove the oil cap, it stumbles a bit. Faint but noticable stumble on part throttle. Now it's 100%

Moral of the story, if you hav you engine out replace the breather gasket, oil press sender and on engine t-stat O-ring at the same time. A couple of bucks well worth it.

Brgds, Learn from my stupidity, Peter

 

So where was the vacuum leak?

 

Good job on your fix. But, I do not think your t-stat O-ring was your vacuum leak. Since it sounds like you replaced it w/out dropping the engine again, which is pretty easy on a Carrera 3.2 (but impossible on CIS cars!), and you have to take off the intake boot/AFM and disconnect the idle valve and a few other hoses to get at it, sounds like you could have inadvertently fixed a vacuum leak that you had after you put the engine back in.

BTW the engine shouldn't stumble too much when you remove the oil cap. A tiny bit is normal, but if it is a big difference, then the restrictor may be missing from the upper breather hose to the filler neck. Sometimes people forget to put the restrictor in the new hose from the old one when they replace it (which should also be done if you have engine out!).

 

Actually, I only removed the cone filter & flapper box to gain access. I checked but didn't find any disconnected or loose v-lines so I can only assume the v-leak was getting past the o-ring. That's my theory and I'm sticking to it :-) As I mentioned, the stumble was faint but noticable like when the case loses pressure i.e. oil cap off. Either way no more leak and no more stumble. I'm happy.
Peter

 

hey Chris what does the restrictor look like ? Mine stubles a fair bit when i take the cap off, but never stalls. Is it on the tank end or the other end , can you tell if you have it by looking externally ?

Thanks

 

Iceman the restrictor is a cone-shaped piece of metal with a small hole in the middle stuck in the end of the upper breather hose the connects to the oil filler neck. It is usually right there next to the filler and you can often see the outline of it if it's there. If not, pull the end of the breather hose off and look. If it's not there, you could probably make something that would work.