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I recently installed a 400 with a high volume oil pump and have had nothing but problems. oil leaking out of the intake manifold bolts (permatexed and a couple still leak) and oil leaking out of the distributor gasket ( changed gaskets, tightened, etc ). Is there any problem with just going back to a stock pump? I seem to be building way too much pressure in the crankcase. I never had this problem with the 350 with the stock pump.
The engine seems to be fine when I'm taking it easy, but when I get on it the trouble starts and the blue smoke appears from oil falling on the headers....I hate blue smoke!!!!!
Any thoughts on this will be welcome.
Thanks Guys!!!!!
sounds like you may have a HV /HP pump.?, Ive always used stock m55 mellings pumps in my engines, if they're street driven. I had a dyers 6-71 S/C 350, 68 camaro back in the eighties, and ran a stock pump no problems, on the street of course.
if you're blowing oil out of gaskets and bolts, sounds to me like you have a crankcase pressure problem, pcv valve working? or alot of blowby the rings.
Oil pressure and base pressure are 2 issues here and being a 400 block and if it was just bored and honed with out a Torque plate which most local machine shops don't believe in your problem is probably a blowby issue as 400 blocks with he thin decks thin cylinders and the head bolts being extremely close to the cylinder bore will show more distortion then a 350 block will.
It hard to get round rings to seal in cylinder bores .003 distortion or more
Do a leak down test at TDC on each cylinder and if its over 8% you have some ring seal issues.
That's the point...doesn't help him much if we don't fix his problem.
We could lower it to 10psi and it would still have blowby.
JIM
I absolutely agree, I was responding to a previous post
The OP's question was "Is there any problem with just going back to the stock pump?" The answer is, "No."
this quite true, there should be no problem going to a stock pump, but that isn't going to fix the problem. The fact that none of the leak locations are located at a point of direct oil pressure is a big clue. The OP is suffering from increased crankcase pressures which is independant of oil pump pressure.