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L98 Oil Leak


New Member
Aug 12, 2018
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Members Ride
WM Caprice L98
Just a post to inform about my experience of finding one of those annoying oil leaks. I recently had a pretty severe oil leak, which looked a lot like a Rear Main Seal had gone looking at the driveway. The smell of burning oil leaking on my cat was driving me nuts, the smell seemed to get worse when I gave the car some stick.
Oil was leaking from the rear of my sump, which got worse after oil change (fresh oil thinner), was dreading checking it out and maybe confirming the worst!! I got the thing on a hoist to check it out and the oil seemed to be coming down from the rear of the engine, but the fresh oil was coming from far higher than what would be from the rear main, which to me was good news.
I had read about the oil pressure sensor leaking, but this seemed pretty dry around the threaded area.
I ended up taking the intake off to look further and, yes the oil sender was dry but the rear of the valley cover plate was leaking badly. When taking my valley cover off, I found that 8 of the bolts were loose, not even finger tight.
Replaced gaskets and torqued up all the bolts to correct torque when putting it back together & it has been all good since.
Has anyone else ever had this with their valley cover plate, as I am interested in finding out if this is a common occurrence?