No Oil Pressure

[bluewedge350]

Got the car out of the garage yesterday to find I had ZERO oil pressure on the gauge and the warning light was on. It was fine when I last ran it ten days or so ago. Does this sound like the oil pressure relief valve failing?

J

[19560]

No. Relief valve failing means high pressure. Relief valve sticking open means low pressure, not zero. Is there any oil on the garage floor? May also be a blockage in the pickup or pump related. I'd be concerned.

[jvaughan]

19560 said:

No. Relief valve failing means high pressure. Relief valve sticking open means low pressure, not zero. Is there any oil on the garage floor? May also be a blockage in the pickup or pump related. I'd be concerned.

umm not entirly correct. My oil pressure relief valve stick open and I lost all oil pressure on my 400SE back 2 years ago.
There is a modified pressure relief valve that can be used on the V8 .. mine was origional.(not replaced and working fine).

Jason

[streaky]

Oil drained out of pump? Isn't there (supposed to be) a NR valve in the filter? If so, perhaps it's stuck open. I am probably wrong on this though - Streaky

[adam quantrill]

Sometimes mine is zero for a couple of seconds when first starting after a week or 2 of no use.
Check the level with the dipstick then if OK restart and blip the throttle - it should come back. If it doesn't you can reprime the pump through the remote oil filter mounting - see the wedge bible "Adam Quantrill" method.

[350matt]

Try giving the pump body a tap with a suitable mallet and drift, to try and 'shock' any sticking valve loose.
If this works take the relief valve out and check for marks in the bore and on the piston both of which can be very carefully polished out, alternativly replace the piston and spring. Unfortunatly if the bore is distorted then it is probably new front cover time.

Matt

[bluewedge350]

jvaughan said:

umm not entirly correct. My oil pressure relief valve stick open and I lost all oil pressure on my 400SE back 2 years ago. There is a modified pressure relief valve that can be used on the V8 .. mine was origional.(not replaced and working fine). Jason

This is exactly as happened to my brother-in-laws V8-M which made me think the same has happened here. There is plenty of oil in the sump and nothing on the garage floor.

If I understood correctly the relief valve can be replaced as single unit and that there is a modified version available (presumably to prevent this happening). Tx everyone for the advice.

J

[19560]

If it is just the relief valve then you can just clean it and replace it but renew the spring (which fails through fatigue.) I've known just as many problems with the modified one...