78 3.0 Oil Leak CIS with Pictures

[tadel001]

I just installed a 3.0 in my 76 911s. I have an oil leak in the rear of the engine. I am pretty sure it is not the oil cooler. I have included three pictures (2 of the leak area and 1 of a weird plug that is not connected - the weird plug is 1/2" diameter and has two metal prong connectors). Any ideas from these pictures where the leak is coming from? Can it be fixed with a partial drop?

[stormcrow]

It looks like that is the engine breather outlet that goes to the oil fill tube. On mine I have the opening with the cap for putting oil in the tank and along side it is anothe opening for the engine breather hose.

Steve

"A Porsche does more then just go fast in a straight line.

[Gunter]

Can't make out clearly but, is that the top of the breather cap?

If so, there should be a breather hose going from the cap to the oil filler stud right under the oil filler cap.



In the picture you can see the 3 usual suspects for leakage: Breather cap, oil light switch and oil thermostate.

Replace gasket under the breather cap and attach the appropriate hose with a clamp going to the oil filler stud, also with clamp.

Replace oil light switch if suspect. (They are cheap)

Open oil thermostate 2 screws and replace the O-ring.

Also, could it be that you overfilled the oil? How does the inside of the airbox look?

[stormcrow]

Looks like you missed installing your breather hose. Here are some pics I took trying to represent the same position you took yours.





Hope this info helps. The breather hose goes to the oil tank fitting on the bulkhead.

Steve

"A Porsche does more then just go fast in a straight line"

[Gunter]

Nice pictures, Steve.
I recommend using hose clamps on the ends of all hoses; they can get loose as I found out.