Oil weeping.....pressurized crankcase?
Thread Starter
Joined: Sep 2004
Posts: 3,148
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From: Downers Grove, IL
Oil weeping.....pressurized crankcase? I have had several oil leaks for a while now and I`m wondering if they are all related. There are always drips of oil coming off my oil pan and after I looked at the engine last week I discovered this. The valley cover is weeping oil at the gasket, the oil pan is weeping at the gasket, the rear cover and or rear main seal also appear to be weeping/leaking oil.
Nothing was loose, and all the gaskets look ok on the outside. I can`t believe that this is a coincidence and that I need new oil pan, valley, rear cover gaskets and a main seal? I checked the PCV valve and it seems to be sucking on the crankcase at idle. But what would cause a valley pan gasket to weep oil other than crankcase pressure??
Nothing was loose, and all the gaskets look ok on the outside. I can`t believe that this is a coincidence and that I need new oil pan, valley, rear cover gaskets and a main seal? I checked the PCV valve and it seems to be sucking on the crankcase at idle. But what would cause a valley pan gasket to weep oil other than crankcase pressure??
Its pretty common to see the valley cover "weep" as you call it. There will not be a discernable oil leak, but you will get a film of oil that collects dirt an makes a mess. That is nothing to be concerned with, and is hard to stop. The issue with that is that a lot of the crankcase pressure collects there and is not really vented. Even though the PCV is functioning correctly, it can't outrun the escaping combustion gases completely, so don't be too worried with it. Use some degreaser on it, power wash it and go on about your business.
The leak from the rear would concern me more. Look and make sure your oil pressure switch isn't leaking. I've seen these blow oil into the connector on more than one occasion. Also check the CMP. Since it sits right in the main galley it also is prone to leak. There is a well right in the bellhousing area above the rear cover that it sits in that can fill up with oil over time and make a nasty leak. Generally when I see a customer's car/truck with an oil leak from inside the bellhousing, I'll price them a rear cover gasket, rear main and a CMP to make sure any possible leaks back there are terminated. Hope this helps!
The leak from the rear would concern me more. Look and make sure your oil pressure switch isn't leaking. I've seen these blow oil into the connector on more than one occasion. Also check the CMP. Since it sits right in the main galley it also is prone to leak. There is a well right in the bellhousing area above the rear cover that it sits in that can fill up with oil over time and make a nasty leak. Generally when I see a customer's car/truck with an oil leak from inside the bellhousing, I'll price them a rear cover gasket, rear main and a CMP to make sure any possible leaks back there are terminated. Hope this helps!
I had the same problem but I justupgraded to the ls6 style valley cover and the oil dirps went away. I also notice that the knock cover boots where torn and oil was all on top of the knock sensosr as well.
