I have fought an oil pan leak for years in my SB 350. I replaced gaskets/pans and used enough RTV to last a lifetime. The pan would always slowly drip from the very back of the pan. I decided to live with the leak and move on. On a separate issue, during hard acceleration, small amounts of oil would come out of the driver side breather cap. The Edlebrock valve covers are not baffled causing the oil to sling out of the breather and slowly drip on the header. The Mr. Gasket baffled grommet that I purchased did not fit my valve covers so to remedy this problem I cut a small hole in a rubber cap (typically sold with valve cover breather grommets). My thought was this would slow/stop the oil from escaping out of the valve cover. This worked but it also solved another issue; the oil pan leak. My thought is that the open breather grommet didn't allow for enough back pressure for the PCV system to effectively work. So when I restricted the opening of the valve cover breather, this provided enough vacuum in the crank case to stop the oil pan leak. It hasn't leaked a single drop since I made this change and I'm afraid to ever touch the valve covers again since it's fixed. Does this logic make sense and has anyone else experienced similar issues?
I have not tried this product myself but there is an aftermarket adjustable pcv valve that you can get. My understanding is that a proper flowing pcv valve system will prevent excessive crankcase pressure from building up. Excessive pressure may cause a leak. I think the adjustable pcv valve is a good idea but it cost quite a bit for what it is. Adjustable PCV Valve: http://mewagner.com/?p=1706
It makes perfect sense to me. Now your crankcase is under vacuum and helping to hold the oil in. With no vacuum the oil can just leak out if it finds a leaky spot.
If you have replaced your oil sending unit recently and not sealed it properly it can leak down over the oil filter housing and appear to come from the rear seal, this happened to me.
