Oil Pressure drop big time

ok its me again this is what i found after some research in the rover web Low Oil Pressure
See Also Low Oil Pressure Warning
From Martin Redgewell-Flack 1990 827

Hope you can help me anyone...
I have a Rover 827 1990 (non Cat) with a lack of oil pressure.
To list what i have already tried:

New oil pump
New 'O' rings in all pick up pipes and a good clean (they were ok anyway)
New Big end bearings
Checked the oil cooler pressure relief valve
Removed and checked the spring in the pressure relief valves in each head.
I have a gauge in the oil switch hole and the pressure is 3lb/ft at idle and rises up to a maximum of 8lb/ft at 2500 rpm, the pressure does seem to rise and drop between these two values.
I don't want to run it too much incase I damage the new bearings.
I wondered if there is a common fault that is known with this engine, I am now at a loss of what to try next.

The hydraulic tappets and a little noisy, but as the pressure rises to the 8lb/ft mark they start to quieten.

Can anyone help me please !!!!

Martin Redgewell-Flack

Dave,

As you are aware I wrote to you in the hope that you could solve a lack of oil pressure on my Rover 827 Vitesse, I had tried all route to solve the problem Sludge, blockages Etc but without success. I replaced the Oil Pump, Big ends and still no pressure.

I tried to pump air from a compressor in the oil galleries to see if there was a huge air escape from somewhere but all looked Ok.

My last effort finally solved it, I made a new long straight pick up pipe, which was in a large tray of fresh oil 3/4 full, the idea was to run the engine and see watch to see if large amount of oil was exhausting away.

What I actually found when I ran the engine was that I had oil pressure running the engine with the sump off and using a bucket if oil. It had to be the pick up pipe, I checked it still looked ok. I checked it for crack, none found.

To cut a long story short, I measured the distance between the bottom of the block where the sump bolts on and thebottom of the block, and the bottom of the block and the bottom of the pick up pipe and the distance was the same. So the pick up pipe was resting on the bottom of the sump. The problem was a small dent in the sump, so small it was impossible to spot, when I straigthened the dent, the clearance between the sump and the pick up pipe is 5mm so only a small dent can cause this problem and so much anger.

All is well now, and the engine seems no worse for wear and it runs now with 20 psi at idle rising to 60-70 psi at 2500rpm.

Thanks for all the help and i hope this may help someone else in the future.

Martin Redgewell-Flack

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I like your Rover 800 page very much ---
Low Oil Pressure A couple of pointers to these problems on the 800

1)A failing oil switch is a major cause of roadside breakdowns on Rover 800 (also the 200 range). the standard oil pressure switch on all Rover engine is pretty poor quailty, replacing it with a new switch usually cures any problem -- not sure if this also holds true for the Honda V6. When replacing the switch always use a genuine Rover switch as it is the only way to be sure you get the correct one -- it works in the opposite sense from most oil pressure switches in that the contacts close as the oil pressure rises as the fuel pump relay is triggered by the engine oil pressure this can result in no fuel supply to the engine.

2) Oil viscosity --- some modern synthetic and semi-sythetic oils are very thin and can give rise to low oil pressure, this is however not harmful though for peace of mind some owners may wish to use a 10w/50 oil.

3) Sludge --- in extreme cases of sludge try flushing out the system with a flushing oil or additive before changine the oil, this might work instead of removing the sump which can be difficult becuase of seized bolts on the engine steady bar.

A recent tip from the USA passed on by an source I have great respect for is to use a litre of Auto Transmission Fluid as a flushing additive as it contains a large proportion of detergent and anti varnish additives. I have tried this and it appears to work better than commericial flushing agents.

Andrew W. MacFadyen [email protected]

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Note 3 lbf/in2 is approximately 0.2bar. 8 lbf/in2 is approximately 0.55bar. The Haynes manual only gives oil pressure for the 2.0litre engine which should be 0.7bar at idle and 3.8 bar running respectively. I am unsure of the correct oil pressures for the 2.5 and 2.7 litre engines and would be interested in putting them on the site.

Dave Pallant

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The North American Sterling factory manual lists Idling Oil Pressure as 10 PSI at 80 degrees C

Running Minimum Oil Pressure 50 PSI at 3000RPM.

Relief valve opens at 70PSI
Low oil pressure switch closes at 4.3PSI

What could be causing low oil pressure? Perhaps a non-spec. or defective oil filter? Blockage in the oil pickup in the sump?

Peter Cohen

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Hej!

I had a similar problem, witch resulted in a broken camshaft (i think it was caused by low quality oil and too long intervals between oil replacement, because the oil had gone stiff and had blocked the oil pipes). When fitting an other cylinder head I removed the oil filter, the rocker cover, the oil gallery and the camshaft. Using an air compressor I blew air the reverse way though the oil pipes, then I pour some oil in the pipes and blew again. This solved the problem. The operation can be done without buying gaskets, you only need some sealing compound and a moment spanner.

Med venlig hilsen

Eddie Louring