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Oil Leak after running

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healeyboz

healeyboz

Jedi Knight
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Hey fellas,

It has been a long time. Car is doing great... I was working on a buddy's BE this morning because he told me that he yanked the oil pan off a fresh rebuild due to a streaming leak. I installed the gasket for him and sure enough, after a few minutes,,,, it was pouring out the rear of the motor. Thinking back to my days of posting on here, I remember soemone else having a similar problem and it is probably common. I remembered a crank case pressure issue and took his timing cover breater off. It stopped the leaking while running, but when you shut the motor off it leaks quite a bit more than the "usual". Thoughts??? I also remember fellas adding more verntilation retro fitted breather that fit to where the original mechanical fuel pump attaches. More thoughts????
 
Any PCV system installed?
 
PCV should be fitted if you want to keep the oil in the engine. Stands for Positive Crankcase Ventilation. In other words suction on the crankcase and far less tendency for the oil to be pushed past the rear crankshaft scroll.

Kurt.
 
As Kurt said- no PCV system = no oil (it will all squirt out without PCV hooked up properly)
BillM
 
Billm said:
As Kurt said- no PCV system = no oil (it will all squirt out without PCV hooked up properly)
BillM
Click to expand...

And it's really pretty easy to do. I just did this myself with the old pancake style one (between the oil separator and the intake manifold). Harmless enough.
 
Barry
Do you have the "late-model" SU carbs that have the "Y" pipe going from the carbs to the chain cover? If so then you DO have PCV already.
BillM
 
Nope. My chain cover runs to a pretty little catch can mounted to rad support. I'm sure there is a pic on here from a few years ago. Pcv valves also CAN make this problem worse under the right circumstances.
 
You should have a hose from that catch can to either a "Y" junction between the carbs OR to a PCV valve attached to the intake manifold.

Here's a simple test to determine if you have too much crankcase pressure. Remove the oil cap and place a piece of plastic wrap over the opening while the engine is idling. If the wrap is sucking in, it's fine, but if it is blowing out, you have too much pressure and it will force oil out the rear. If that's the case, install the PCV valve or "Y" between the carbs and try it the test again.

When I did the test, the plastic wrap was being pushed out, so I swapped out the PCV valve with another one I had and it fixed the problem. No more gushing oil out of the rear of the engine.
 
Maybe someone installed the oil pump cover incorrectly... or not at all.
 
I recently had a major oil problem about 40 miles from home. Oil ws running out the rear of the oil pan when the engine was running. The higher RPM the more oil. Engine was running OK...no odd noises. Turns out, I had a blown headgasket that leaked only to the oil galley that pressurized the head. I do have the vent hose from the valve cover to the carbs and the vent hose from the timing chain cover to the carbs. It didn't make any difference---the oil kept coming out of the oil pan. I lost 14 quarts in 40 miles. I guess because the combustion chamber pressure was so high, and there being an access to the oil line 'piping', it blew the oil out the back via the rear main bearing. So I put in a new headgasket and no more leaks! I didn't have to change the pan gasket either. I thought for sure I'd have to do that , and I even bought a new pan gasket, but it never leaked a drop after that. Don
 
All the previous suggestions are the first line of defense and will in many cases cure the problem when done correctly. The OEM "tophat" style works best. Venting to atmosphere does not make use of the scroll seal as was designed. However, if the half moon seal was improperly fitted or not line bored in place when the crank was fitted, you may never cure it. My lip seal conversion will, and have had several testimonials to that effect. Works with or without the 5 speed conversion.

Contact me off list if you have additional questions about it.
 

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