Oil Pressure Problem
Discussion
Oil Pressure won't go above 40psi. Immediately suspected sender but have just checked with mechanical gauge and that says the same. It ticks over at 40 cold and drops to 25 when hot. At 2000rpm it's 40psi hot or cold. Only thing I can think of is failed oil pressure relief valve? Anybody got any other theory's? Looking like grubby hands time!
Rob.
Rob.
Sounds like oil pressure relief valve sticking open a bit to me Rob.
Not seating properly?
Or partially blocked pick-up strainer, leaking or loose pick-up pipe, or oil pump on the way out.
Were the symptoms gradual or sudden onset?
There is a thread about disintegrating cork gaskets on a PH TVR forum. Search 'Another RV8 Saved'
Not seating properly?
Or partially blocked pick-up strainer, leaking or loose pick-up pipe, or oil pump on the way out.
Were the symptoms gradual or sudden onset?
There is a thread about disintegrating cork gaskets on a PH TVR forum. Search 'Another RV8 Saved'
Mine sits about the same as yours and always has (perhaps nearer 50 when cold but definitely 25ish when hot and idling). Did before engine rebuild does after engine rebuild and never varies other than by oil grade, it used to sit lower when I used 0/40 now gone to 10w50. However if yours has changed dramatically recently id be worried, but have you done an oil change?
Note with engine rebuild all oil ways were cleaned and flushed, oil pump overhauled and checked and still sits at those pressures.
Note with engine rebuild all oil ways were cleaned and flushed, oil pump overhauled and checked and still sits at those pressures.
Edited by mep12345 on Saturday 21st February 20:16
glenrobbo said:
Sounds like oil pressure relief valve sticking open a bit to me Rob.
Not seating properly?
Were the symptoms gradual or sudden'
Pressure dropped suddenly but with no strange noises, tick over pressure not changed. Will give Burton Power a ring next week and seek some advice / parts. I'm thinking new pump and shell bearings while I'm at it. Just need to do a bit of a chassis mod first to get the sump off.Not seating properly?
Were the symptoms gradual or sudden'
Rob.
Yep, a bolt-on removable cross-member a la Phillpot is definitely the way to go.
Ivor ( Sarbec on PH ) and Andy did mine a while back. Nice job from two nice fellas.
ETA:
I wonder if you could drain the sump & chech the pick-up strainer etc. with an endoscope through the sump plug hole?
Ivor ( Sarbec on PH ) and Andy did mine a while back. Nice job from two nice fellas.
ETA:
I wonder if you could drain the sump & chech the pick-up strainer etc. with an endoscope through the sump plug hole?Edited by glenrobbo on Saturday 21st February 18:44
Started investigating the oil pressure drop this weekend, have cut out the crossmember under the sump, removed the anti-roll bar and taken off the sump. Oil pump is off and I was expecting to find a broken pressure relief spring but it is actually still in one piece So maybe just gone a bit soft after 100000 miles. Took off a couple of big end and main caps and there is virtually no wear on the shell bearings. Sump was sludge free and no debris.
Will order a new pump this week and hope that sorts it, meanwhile have got a few bits an pieces to clean up and paint.
Rob.
Edited to add: Main bearing shell after 100k miles,
Will order a new pump this week and hope that sorts it, meanwhile have got a few bits an pieces to clean up and paint.
Rob.
Edited to add: Main bearing shell after 100k miles,
Edited by Griffinr on Monday 16th March 09:45
New oil pump arrived today, there is a noticeable difference between the stiffness of the relief valve spring on the new pump against the old one so I am hopefully the pressure will be back to normal when it's fitted. Just need the sump gasket now and a bit of welding to assemble the bolt in cross member.
Rob.
Rob.
Interesting day today, fitted new pump, sump back on, filled with oil and started up. Pressure went off the gauge, oil filter can inflated and the seal blew out dumping all the oil on the drive, oh dear! (Or words to that effect). Just emailed the supplier so see what they have to say next week.
On the up side the bolt in crossmember mod went well.
Rob.
On the up side the bolt in crossmember mod went well.
Rob.
Now I'm confused
fitted the old pump this afternoon and now have textbook oil pressure??
The only other thing I have done on this job is beat the sump back out into the correct shape as it had been flattened and I suspect was very close to the oil pickup. Maybe so close as to restrict the oil flow particularly if it had gathered some crud around it. That would explain why the oil pressure went up a bit as it got up to temperature.
Looks like I'm sorted, just got to put crossmember back and anti-roll bar.
Rob.
fitted the old pump this afternoon and now have textbook oil pressure??The only other thing I have done on this job is beat the sump back out into the correct shape as it had been flattened and I suspect was very close to the oil pickup. Maybe so close as to restrict the oil flow particularly if it had gathered some crud around it. That would explain why the oil pressure went up a bit as it got up to temperature.
Looks like I'm sorted, just got to put crossmember back and anti-roll bar.
Rob.
Finally got the car back on the road today after much cutting, carving and welding to make the exhaust fit better and closer to the underside. I recon I now have an extra inch of ground clearance so should miss most of the speed bumps instead of hitting all of them.
The oil pressure issue is now resolved, it was all down to the sump damage restricting the inlet to the oil pickup. I have the original pump back on and get 50psi at 1500 rpm hot on new oil. Tick over is about 30-35 psi.
Rob.
The oil pressure issue is now resolved, it was all down to the sump damage restricting the inlet to the oil pickup. I have the original pump back on and get 50psi at 1500 rpm hot on new oil. Tick over is about 30-35 psi.
Rob.
Griffinr said:
Interesting day today, fitted new pump, sump back on, filled with oil and started up. Pressure went off the gauge, oil filter can inflated and the seal blew out dumping all the oil on the drive, oh dear! (Or words to that effect). Just emailed the supplier so see what they have to say next week.
Rob.
Any reply from the supplier Rob?Rob.
Good to hear your original oil pressure problem is now resolved.
glenrobbo said:
Any reply from the supplier Rob?
Good to hear your original oil pressure problem is now resolved.
Nothing from them yet, I have requested a refund as I no longer need it and the one they supplied was either faulty or incorrect. Will ring them again next week and hopefully get some action. I bought through their eBay shop so can always start a "dispute" if I need to. Meanwhile it's just nice to be back in the S, been using my sons track day MX5 recently, ridiculas wheels and stupidly low, fun but not an S.Good to hear your original oil pressure problem is now resolved.
Rob.
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