P38A Diesel, what oil pressure should I have?

Hi Guys,

Since lossing nearly all the oil from the engine when not fitting an secondhand oil cooler properly I have added a mechanical oil pressure gauge to the engine via the oil pressure switch to see what oil pressure there is in the engine.
So.
When started up the oil pressure was 30psi ( I assume it is psi)
Left to idle then a little drive around the block, just to the end of the road and back.

No funny noises and drove ok as best as could tell.

Back on the drive about 30psi and when revved to about 3000rpm, perhaps a little more and pressure slow rose to 50psi taking about 20 seconds.

It dropped back to 28psi when back on tickover.

Thoughts please? Could put the video on if any body wants to listen.

Thanks in advance.

I think (and this is from the Petrol model btw) - oil light comes on below 15psi, and running pressure at 2500-3000 rpm is around 45psi, not sure what idle pressure should be.....but around 30 I would say is OK.....remember this was for the petrol model - I'll have to fire up RAVE and see if the diesel pressures are listed.

Thanks Saint.V8

I have had a look through RAVE but the info has eluded me.

Looking through the internet found this:

http://www.landroversonly.com/forums/f40/installing-oil-pressure-gauge-96922/

which had a comment with this info in:

"4. If your engine is cold, no, you don't have to drain the oil. The hole locations are above the oil level in the pan. You might get some residual seepage, but nothing serious.

Your pressure readings should be:

Cold Idle: 50 PSI
Cold 2K RPM: 50 PSI
Hot Idle: 10+ PSI
Hot 2K RPM: 40+ PSI

Those are pretty much rock bottom numbers. Anything below that and you'll have issues. My own D2 reads 52 PSI cold, 14 PSI Hot Idle, 47 PSI Hot 2K RPM.

I've recently installed this gauge and I love it. The digital/analog combo is super useful for getting accurate readings, install is a snap too."

But not entirely sure which engine/landy they are talking about.

Perhaps will fit the oil pressure gauge permanently and just see what happens. Won't book the ferry tickets for Noway just yet though. Blast! (By the way that is not what I said when the oil was all over the drive)!

Any other suggestions?

He mentions D2 in the excerpt you have quoted.... This had the TD5 engine I think.

Jerseyp38 said:

Hi Guys,

Since lossing nearly all the oil from the engine when not fitting an secondhand oil cooler properly I have added a mechanical oil pressure gauge to the engine via the oil pressure switch to see what oil pressure there is in the engine.
So.
When started up the oil pressure was 30psi ( I assume it is psi)
Left to idle then a little drive around the block, just to the end of the road and back.

No funny noises and drove ok as best as could tell.

Back on the drive about 30psi and when revved to about 3000rpm, perhaps a little more and pressure slow rose to 50psi taking about 20 seconds.

It dropped back to 28psi when back on tickover.

Thoughts please? Could put the video on if any body wants to listen.

Thanks in advance.

Click to expand...

That should be fine if it's 28 psi at idle warm it will be ok.

Thanks Saint.V8 hadn't noticed that or at least registered what it was saying!

Thanks Wammers, that makes me fell better when someone infinitely more knowledgeable says that. Have changed the oil and afraid I have added some Lucas oil Stabiser. Ran the engine and a short drive and showed about 32psi warm idle and went up to about 56psi when revved to 3000ish rpm. Guess have to go with it but know I will have that sick feeling the first time I get off the ferry on a long haul trip! Will try and do one without the family first!

I have removed the mechanical gauge but might well fit an electric one, might add amps as well. Finding an adaptor to accomadate the original and a gauge will be the challenge I guess.

Other jobs on the to do list before going away:
Suspension pump rebuild,
All other oils,
Check steering joints,
Take the brakes to garage for a test,
Change the power steering fluid,

Expect I will find other but they are the ones I a man thinking about.

Cheers for the help, expect I will be back soon!

Jerseyp38 said:

.......
Thanks Wammers, that makes me fell better when someone infinitely more knowledgeable says that. .........

Click to expand...

I said the same thing....(albeit I was referencing values from the V8's) - I still said around 30psi would be OK....

Yours,
Miffed of Surrey....
D)