Kevin Baker

Help me remember the circuit for the oil. No oil pressure as evidenced by the gauge and idiot light.

Started as a brief lack of pressure a cold start. Was due for oil and filter. Changed just like usual. Mobil 1 15w50 Mahle filter. Started fine other than brief light at start. Drove about 45 miles sat overnight.

Next morning no pressure, started and turned off within a few seconds, pulled dme relay cranked wouldn't make pressure.

Tonight pulled Oprv didn't seem to be in a bind. Checked alignment with tool. No oil pressure.

Removed starter, installed flywheel lock checked torque on crank, seems pretty damn tight. Starter back in no oil pressure.

Pulled oil filter, full of oil. So seems oil is making it from pan to filter. Just not to crank

mj951

Have you tried replacing the oil pressure sending unit?

Kevin Baker

I don't think it's an instrumentation problem, granted I don't "run" the engine, when it fires it sounds like there is no oil pressure so I shut it right down

Butters944

Does your car leak at the crank seal? My seal deteriorated, causing the oil pump drive sleeve to lose tension. If I recall correctly I couldn't tell, the crank bolt seemed tight. Just another idea to brainstorm..

Kevin Baker

Butters, thanks I will be getting in there Saturday to check

harveyf

Kevin, look here:
http://newhillgarage.com/2013/06/25/...tem-explained/

A cheap but messy experiment. Remove the oil filter and crank. You should see a gusher, which will re-assure you that thinks work up to that point. It is rare but I have had at least one brand new oil filter in my life that had a blockage.

It would be interesting to know if the oil pressure sending unit can fail such that both the gauge and the idiot light are affected. I don't know.

John_AZ

Nice work Harvey^.

It could be a crack in the oil pick up tube or the small tube seal.

or...another idea..
Here is a Tech bulletin:

Kevin Baker

This is why a love this site!! Thanks guys. Going to pull front cover Saturday!

Kevin Baker

Harveyf. I pulled the filter, there is oil at and in the filter.

The gauge will move with engine revolution while cranking with dme relay removed, idiot light stays on even when gauge is at 5 bar. When I start the engine the gauge drops to 1.5 or 2 bar, which if hot at idle I would not worry about. But it clearly is not making pressure based on what I hear.

harveyf

I re-read the post a little closer. It sounds like you may have a small leak path on the suction side, which may be getting worse, that was allowing oil to drain back overnight. If the leak path is getting worse, you wouldn't be able to get prime but if that was the case you wouldn't have oil at the filter.

Only because it will really cheap and easy, I would try a different filter, although I think there is a low probability of that being the problem. Another approach would be to drain oil and go back with a straight 50 wt, again just as a test to see if the heavier oil can compensate for a small leak path. Not a long term fix, just diagnostic in nature.

From there it gets ugly. Looks like the Tech Bulletin could be done in place but beyond that you're going to be tearing the engine down.

Rule out the sending unit before you go that route!

Kevin Baker

I have another filter on the shelf. Almost tried that last night! I thank you for the concern and taking the time to help me.

I'm somewhat suspicious of the crank seal allowing air and causing the pump to cavitate.

Van

Cracked pickup tube? Do you run balance shafts? And they're timed correctly?

Van

p.s. here's a picture of a cracked tube.

kevin12973

When/if you start it, do you hear lifters clacking? If not you have oil pressure and a bad or stuck gauge.

mj951

10-4, was hoping for an easy solution which is not always the obvious one.