308 oil leak under intake plenum ?

Not a different area, but sometimes the oil pressure sensors themselves can leak/weep at the swaged and/or potted sealing joints on their bodies (not where they screw into the casting) which can spray/drip oil in an unexpected direction -- just something else to check (since you report that the casting is clean)...

 

Check the oil breather hose fromthe oil seperator to the air cleaner, that might be spitting a biut of oil.

Make damn sure that the cover over the flywheel is sealed, (the one used to check timing). You do NOT want oil dripping down onto the clutch.
hth,
chris

 

I hate to say this... but, if you've ruled out the oil filter mounting / lines / sensors and the breather hose, you've only got (2) other sources for oil in that area ---- cam cover gaskets and cylinder head gaskets. If these leak on the inboard side of the V, the oil can run down the sides of the heads and collect in the area on top of the block. With an inspection mirror, you should be able to see if oil is running down the sides of the cylinder heads anywhere.

 

I don't know what year the idiot light started to get installed for oil pressure (my 1975 doesn't have it), but if your car has an idiot light for oil pressure then you have the easy-to-see gauge sender poking out over the clutch side and a smaller harder to see switch on the other side. A 308GT4 here had a leak through that switch filling up the valley with oil. It is a sort of common switch according the local auto parts store, shared with Saabs or something. The thread size is 14mm x 1.5mm (or was is 1.25?) non-tapered thread with a crush washer, different than most european cars with a tapered thread that are about M10. I blew compressed air into the switch and oil bubbled out right under the connector.

 

Why couldn't it be the oil filter gasket?

 

Here's one for the books. When I last put together my engine, I also stripped and refinished the valve covers. When a mysterious oil leak occurred, I figured I screwed up the valve cover gasket, so I replaced it. Still, there was an oil leak. It tuned out, the valve cover was porous and when hot, oil seeped though the alloy. I stripped that section of the valve cover, coated the area with epoxy, repainted the cover and voila, no more oil leak.

 

My 308 is not supercharged or turbocharged but the pool oil where you describe was from the vapor system.
Since you have did recent maitenance on these componets I have to ask was it there before you did this service?

My Porsche is turbocharged and has positive manifold pressure which would make these componets more likely to leak.


stephen

 

I was in kinda the same boat- I bought 16 BBS wheels with tires mounted and balanced.
It took me time to get used to bigger contact patch, but then all I could notice a 'shudder'.
I started looking at suspension, steering.......turned out the tikes were out of balance.
I stood there as every wheel was put on the balancer, and every one was out of balance.

Sometimes it pays/saves to look at the obvious.

stephen