Low oil pressure

[Barn]

Sadly I may have to sell, I'm running out of money. So far I have purchased new oil pressure switches, oil lntake manifold, oil pump, steering rack, power steering pump, both track rods, track rod ends, steering damper, clutch flexi hose, thermostat, all wheel nuts and more.
I started with the oil pressure switches due to the fact that one was leaking, after replacing the switches the car was fine so I started on the steering overhaul. I was then aiming on going through the various mounts and bushes, I already have black power flex front subframe bushes and front lower arm bushes.
I obviously would not have carried on with the overhaul if I new the oil pressure was going to be a problem. I have invested nearly £1500 just in the steering which could have gone into my now more serious problem.
One thing I did notice today was when the car got hot and the low pressure warning sounded only one pipe going to the oil cooler was hot the other one was almost cold ?
The valve behind the pressure sender seems to work as the top end doesn't ever rattle on start up, so I take it oil is not running back.

[twoqu]

If we discount the steering from the equation then we are left with a few ideas.
Apart from the viscosity, the only other tempearture dependent item in the oil system would be the thermostat built into the oil filter housing. Not sure how you can verify that without just feeling the pipes.
You have also disturbed the large temp sender which has the non return valve installed behind it. I am not sure what happens if that malfunctions or whether it could fail in a temperature dependent way. I know it largely to prevent drain back from the head but presumably the pump needs to work against it.
To be honest can't see what what cause the issue with the car just sitting. There has been a case recently of the oil pump drive loosing but that engine was subjected to excessive abuse far beyond normal operating conditions!

[Error404]

I want a cheap RS2

[Barn]

Just carried out a wet oil pressure check using the smaller oil pressure sensor hole.
With a hot engine 10psi at idle and 22psi at 2000rpm ?????????? not good.

[Barn]

When I got the car the oil pressure sender was leaking so I changed both of them with new audi parts, ran the car and it was fine, 2.5 bar at 2000rpm hot.
I then carried on with the steering work and when I finally got it back together the problems started.

[AndyP]

What was oil pressure like before you had this work done on the steering?

[Thuppu]

Quite much wear, how was the total clearance?

[Barn]

Well after a long day I have got another oil pump fitted to my RS2 along with new oil intake manifold and two new sump gaskets, I have also purchased some 5w/40 engine oil.
Guess what great oil pressure from cold, but once she heats up the oil pressure drops and the alarm still sounds, am I missing something or being totally thick, what else can it be. The oil pump drive lever was solid, the main bearings are perfect with only 0.050mm of wear.
Any thoughts or does anyone want a cheap RS2 !

[Bowie69]

'Gerotor' looks right to me: http://www.casconpump.com/custom-pum...-technologies/

A conjugation of 'Gear' and 'Rotor' at a guess..... so you are all right(!)

[K Simmonds]

Yeah, if I'd have to make a stab at an answer at say an Audi Enthusiasts pub quiz I'd call it a radial gear pump, which I know is incorrect and I'm yet to Google the term to see how wrong I am.

Anyway, I'd double check the pressure relief valve piston/spring and try running it on a more suitable grade of oil before condemning any major components, especially as you've checked the main bearings and their fine.

[Thuppu]

I don't think it's totally wrong to call the I5 oil pump a "gear pump".

[Error404]

Lets not forget that will be a translation from German. There are all kinds of weird and wonderful names for stuff due to this.
I remember once buying a "dog" in an Audi box

[UrS4boy]

Not in a gear pump. You said it was a gear pump, it's not. Different story.

Not a gear pump? You might want to tell Audi that.

From this older document:



I spy this. Hmm... the fools - they think it is a gear pump.

[Barn]

Thanks.
If it does spin will a new one fix the problem or will I need to get a slightly smaller one made ?

[Error404]

Remove the oil pump and heat the drive up with a torch to around 100deg and see if you can turn it on the crank nose.
I would try running it on a more sensible oil first though