Piston cooling valve V70 2.4T 2001 (No oil pressure)

Bandit7311 · Post by **Bandit7311** » 18 Mar 2011, 11:03

I searched thru the board and found no answer and no idea.

I have oil pressure problems with a V70 2.4T 2001.

Oil pump, including all O-rings in the oil pan have been changed. Oil trap changed and all crank case exhaust openings cleaned.
Engine flushed with motor flush liquid. Still no success and the oil lamp and the warning "No oil pressure, stop asap" comes on sometimes.

Now I have found a part which has to do with the oil circle called "piston cooling valve", what is the function of it and would a failure of this device also influence the oil pressure.

I am german, so sorry for my English.

Thanks
B

Post by **jimmy57** » 18 Mar 2011, 11:37

The valve requires oil pressure to reach 1.5 bar before oil is sprayed on piston undersides.
The purpose is to keep oil light from coming on at fully warmed up engine idling. The oil pump volume may not be adequate when oil is hot to keep oil light off if piston spray jets were spraying oil.
Is the oil light on above idle speed or at any engine speed?
Have you had any cam positioning codes?
Turbo can cause oil pressure loss but is rare. Turbo oil pressure loss is almost always accompanied by very loud turbocharger noises (screeching noise).

Bandit7311 · Post by **Bandit7311** » 18 Mar 2011, 15:49

by jimmy57 » Today, 18:37
Is the oil light on above idle speed or at any engine speed?
Have you had any cam positioning codes?

Jimmy thanks for your answer.

After the oil pump change the oil pressure light seem only to come on when the engine is hot and when you decelerate / engine falling to idling. (if I turn the engine off for 2 minutes the oil pressure light will stay off again for about 10 miles)

And yes, there was a "P0014 Camshaft reset valve incorrect signal"

So you think it could be that valve?

Sascha

Post by **jimmy57** » 18 Mar 2011, 18:12

No, I was curious as all that I have seen that really had low oil pressure usually had a camshaft position code.
Any engine noises suggesting engine damage?
Was the engine really soiled inside when you removed oil sump?
Something could hang the piston spray jet relief valve. It is just below and the the left (rear) of the cam belt tensioner.
I think it is 17 mm head. It is a spring and a ball. If something was stuck in it holding ball off seat then it could be the problem.
If you have a way to check oil pressure it might be helpful to know how low it really is.

Bandit7311 · Post by **Bandit7311** » 18 Mar 2011, 18:33

The oil pressure switch is new. And as I have seen in a data sheet it switches at 0.5 bar (7 psi), so during the lamp is on it really must be below that. And I checked the signal, it really dumps from 12 Volt to 0 Volt, when the oil light comes on.

But I have bought a manometer and will messure the "real" pressure.

The oil sump was not really gunky inside as I thought it would be, there was minor built up of oil coal.

So as you say it is a spring and a ball, can I take the piece out and clean it? Or is it inside a housing?

I looked thru the drawings and do you think I just can take the serpentine belt / the crank damper pulley off and leave the timing belt / crank pulley on for taking out the valve?

The engine runs smooth and quiet, no loud noises... But I also thought about the big end bearings, but everybody who I spoke to said, that you would hear that very clearly.

It seems that the problems only comes up when the oil is hot and thin. I use 5W40 full synth oil.

Thanks
B

Post by **jimmy57** » 18 Mar 2011, 20:05

The valve can't be disassembled but if something is holoding it open I think you'll easily see it. You should be able to push it open and clean any debris out.
The valve can be removed with belt in place. Find it with a mirror, it may be hard to locate without. Probably more easily reached from bottom.
I agree about bearing problems making noises. Bearing damage with no low oil pressure problems has usually shown up as noises when first started in the first engine revolutions.

Bandit7311 · Post by **Bandit7311** » 19 Mar 2011, 12:35

So I took the Piston cooling valve out today.

It was a little gunked up but not to worry about, so I cleaned it and put it back in.

I am really thinking about now to flush the engine again and then use a 10W40 oil instead and see...

Or do you have any further suggestion Jimmy?

Thanks again
Sascha

PS: BTW I was able to get the valve out without removing timing belt

Post by **jimmy57** » 19 Mar 2011, 12:49

You have covered possibilities well. I would use the heavier weight oil and see if that addresses the problem. Using gauged oil pressure you could monitor oil pressure idling warm and then undo turbo oil feed pipe and plug it with a very short bolt sealed with copper washer and see what change it makes. If it takes pressure from .7 Bar to 2 Bar then you have a turbo issue. If it only brings it up .3 Bar then the problem is not turbo.

Bandit7311 · Post by **Bandit7311** » 19 Mar 2011, 18:04

Hmm,

well the Turbo is a used one out of a 30 000 miles car. And with the old Turbo charger it did the oil light problem already.

The Turbo was exchanged because the turbine part in the exhaust side was broken off. (I think it broke off also because of lack of oil)

As we just bought the car and it came from italy, we dont know anything of its history.

Thanks
B

alanjackson2011 · Post by **alanjackson2011** » 18 Nov 2011, 07:40

Hello, I know it's late but did you ever get to the bottom of this? I have a very similar problem with my 2001 V70T 2.4. Fine when cold, no rattles. Just about exactly the same as above. When the oil light is on revving has no effect, only run for a few seconds before turning off though.
I have just had it in the local Volvo dealer and they tell me it is a seal between the head and intermediate unit.
Is this possible? People I have spoken to doubt it. The dealer did not dismantle anything, just connected a pressure gauge. But did manage to charge 3 hours ay £90 per hour !!! Repair quote is over £1000 on top of this. Any suggestions would be most appreciated, Thanks, Alan