5.0 in 86 Van loosing oil pressure

Not enough oil in the oil pan. Did you check the oil?

Oil is full I was wondering maybe if that isnt a sign that it needs changed, maybe is thinned out

If you haven't changed the oil in 5000 mi or more, that is a sign that it needs changing.

Either your oil pressure sending unit or gauge is faulty or you lost oil pressure for real. I am not sure why you could have lost oil pressure for real, but it could be a bad pump, wear on your engine or other things.

Jeff

Or.............all your oil is being pumped into the upper part of the engine and your oil returns are restricted due to sludge buildup. Happens fairly often. All the oil stays in the heads and can't drain back quickly enough. Stop for a couple minutes and it catches up. Drive steady state low rpm and the drain rate probably is equal to or better than the pump rate. Hit higher rpms and pump rate exceeds drain back rate=oil pan runs out of oil.

Bob opined in news: snipped-for-privacy@corp.supernews.com:

I bet we could tell the problem from looking at the dipstick and oil fill

;)

Thanks for the reply, I will drain and run some cleaner through the system

abomb69(zerozero) opined in news: snipped-for-privacy@comcast.com:

Arrrghhhhh!

DONT DO THAT!!!!

1. THere is a good chance that you loosen buildup in the oil passages and it migrates to the bearing feeds, gets lodged and starves the bearing!

2 Also you would have to change the filter every couple hundred miles, afterward, or it will bypass and not filter at all. Then you get "1"

The best bet is to thoroughly drain the oil... use a high quality oil which will slowly dissolve sludge, change filter evry thousand.

Next time START with mobil 1 in a clean engine .. you simply would not believe what the inside of your engine looks like after 150 k on mobil 1.

So when I change my oil next put Mobil 1 in it? or should I put 20w50 in it? I havent put in anything yet to flush it

opined in news: snipped-for-privacy@comcast.com:

If you havent been using much oil.. quart or less per thousand, use mobil 1

10w30 and change filter every 500 miles and the oil at 2000 Use motorcraft or purolator pure one filter... from walmart or autozone or wherever.

next series change filter every 1000 and oil at 3000.

There's 2 reason to use mobil 1, it is very high detergent and it will lube to the max possible even if there's oil starvation at one point or another.

Also Overlooked is the effect of ash point (temp where oil carbonizes) on oil starvation. If oil is deficient, the temp rises on the friction surface and long before the metals degrade, the oil that IS there may start to carbonize... this causes further problems because this typiclly happens at any rough point such as a previous groove, which causes that area to heat more because carbon ash is an insulator.

Also I recommend you borrow or buy a mech gauge and find out what your oil press really is.

Teh engine doesnt use or leak oil,. even with 200k+ on it, the last oil change was whoknows when, I do know they used 10w30.

opined in news: snipped-for-privacy@comcast.com:

THAT is very pertinent info. And we should have got that first.

And it pretty much changes everything.

If it doesnt knock or valve clatter the chances it's sludged up are pretty low.

Definitely get the mech oil pressure gage ... you may have a failing pump.

If you feel up to it, pull the easiest valve cover, it will reflect the oil change history... at least, pull the screen under the PCV valve, if you havent changed it and it's fairly clean, the engine is unlikely to be sludged.

If you HAVE to drive it.. the mobil 1 is still smart, and you can do what I said before. JUst pay attention to how quick the oil turns dark. Not sludged, it should remain fairly clear up to 500 miles

I'd ask around for the name of a good independent mechanic once you have the gauge installed. It's tough to come up with the exact diagnosis - as shown by this thread

The engine does have a little tap to it, sounds like a lifter, but it isnt loud, it has plenty of power, just that little tap that has been there over three years now (I knew who had it before me and before them)

I changed the oil, put in Valvaline, now the ticking is louder, but I have good oil pressure now