Yes, you read it right.On my 66 Nova,about 25 years ago when I half as**d rebuilt the 6cyl, I shimmed the oil pump for more pressure.Well,now that I've been trying to get it going,I revved it pretty hard and popped the oil filter gasket right out and a lot of oil is on the ground.Is there a setup,like a sandwich adapter with lines and a regulator,to bleed off excess pressure? I don't want to tear into the engine.In all them years,it only has around 1,000 miles. Thanks.
How can i bleed off excess oil pressure?
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OVERKILL
$100 Site Donor 2021
What do you have for oil in it? 20w-50?
Find a bypass filter for it. Run 5w30. Or replace the pump with a stocker. Its possible the pressure relief valve is stuck closed.
run thinner oil 0w-30 or 0W-20 and a better filter.
Some of the filters, I think the K&N is one, have the gasket staked in.
Some of the filters, I think the K&N is one, have the gasket staked in.
Originally Posted By: OVERKILL
What do you have for oil in it? 20w-50?
Good one!
Originally Posted By: daves66nova
Well,now that I've been trying to get it going,I revved it pretty hard and popped the oil filter gasket right out
You've heard the old joke where a guy tells his doctor, "it hurts when I do this". And the Doc's reply is, "well don't do that!"
So don't rev' the engine when it's cold!
But seriously, was the relief valve setting that limits maximum oil pressure increased when you modified the oil pump? It sounds like it was otherwise the problem shouldn't have occurred. BTW what is the max' oil pressure and what's the OP at low rev's, on idle and say at 1,500-2,000 rpm?
What do you have for oil in it? 20w-50?
Good one!
Originally Posted By: daves66nova
Well,now that I've been trying to get it going,I revved it pretty hard and popped the oil filter gasket right out
You've heard the old joke where a guy tells his doctor, "it hurts when I do this". And the Doc's reply is, "well don't do that!"
So don't rev' the engine when it's cold!
But seriously, was the relief valve setting that limits maximum oil pressure increased when you modified the oil pump? It sounds like it was otherwise the problem shouldn't have occurred. BTW what is the max' oil pressure and what's the OP at low rev's, on idle and say at 1,500-2,000 rpm?
I rebuilt this engine when i was around 20-25 years old.none of the clearances were checked at all.The oil pressure when hot was maybe 5-10psi, when revving it,it would climb to 40 or so.this was with stock UNSHIMMED pump.I then took engine out and bought one of those stifferbypass springs that give it more pressure.I'm not sure if i also added a washer too,so that it was even stiffer.A little is good,more is better,right? LOL. Anyways,that's how i have that much pressure.Big clearances,no doubt. I'm running 15w40.
If the only issue is the oil filter gasket, why not try a different oil filter that can handle the pressure?
M1 oil filters are supposed to be pretty stout with the extra thick canister and stuff.
M1 oil filters are supposed to be pretty stout with the extra thick canister and stuff.
If you're oil pressure was only 5-10 psi on idle, 40 psi at high rev's, the solution was not to increase the oil pump pressure as that in no way will help the lubrication of the engine.
The low OP is a sign of worn engine bearings.
Increasing the OP just masks the problem.
The solution, short of rebuilding the engine, was to run a heavier oil such as a 20W-50 which does increase OP because more oil is staying in the bearings, not just flowing through them at a faster rate.
The low OP is a sign of worn engine bearings.
Increasing the OP just masks the problem.
The solution, short of rebuilding the engine, was to run a heavier oil such as a 20W-50 which does increase OP because more oil is staying in the bearings, not just flowing through them at a faster rate.
I might just end up taking the engine out and PROPERLY measure clearances and unshim spring.Hopefully that'll help.Oh,engine hasONLY about 1000 miles or so since rebuild!
The other option would be a higher volume pump so you can push more oil at idle. That should bring the idle pressure up a bit.
There was nothing wrong with your oil pressure. 5Psi idling and 40 revved up is fine for that old inline 6
In many engine designs flow VOLUME is just as important as pressure. I seriously doubt that engine has any real problems.
I don't know about that long ago, but in more modern times, GM engines have very low oil pressure at idle, and that's the way they're designed. The Northstar runs about 3-5 psi at hot idle, and it's perfectly happy that way.
That's why Chrysler's Pentastar's 30 psi at hot idle has always been curious to me. I've always wondered why it runs so much oil pressure when you wouldn't think it'd need it. Less than 10 psi at idle is very common for engines these days.
That's why Chrysler's Pentastar's 30 psi at hot idle has always been curious to me. I've always wondered why it runs so much oil pressure when you wouldn't think it'd need it. Less than 10 psi at idle is very common for engines these days.
in all of the engines i've played with, as long as there is enough pressure to keep the lifters happy, pressure at idle is pretty much irrelevant.
however, an interesting exception: the GM 3800s seem to need lots of pressure at all times. every time i've seen one have pressure that looks normal with other engines(~10PSI at a hot idle), bearing death is near(actually, pretty much any under ~25PSI at hot idle seems to be the threshold). does anyone have an explanation behind it?
however, an interesting exception: the GM 3800s seem to need lots of pressure at all times. every time i've seen one have pressure that looks normal with other engines(~10PSI at a hot idle), bearing death is near(actually, pretty much any under ~25PSI at hot idle seems to be the threshold). does anyone have an explanation behind it?
Does anyone know if i can take pan out w/o taking engine out? I want to make sure before i assume that i can and the oil pump prevents it from coming out
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