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

[draser]

After reading all this it looks like some bits of info are missing. Like no engine can run w/out oil pressure. Also, if after replacing the oil press switch the light still comes on the next logical step (or what I'd do if this were my car) is to measure the oil pressure with a gage. If none, the next suspect is the oil pump relief valve. No matter how much wear an engine has there's still some pressure left in there. Basically in any engine the oil pressure level is driven by the main and rod bearings. So if the pressure reaches the crank (oil pump seals are good) you have oil pressure. From the crank it goes everywhere else (cams, oil squirters, etc).

[alanjackson2011]

Many thanks for your very sensible comment. The volvo dealer did put a gauge on the engine (charged £200) and said the oil pressure starts off OK but drops to nothing after four miles.

I have written to them asking what the pressures were at cold and warm - but they have not replied yet.

I havev always panicked and stopped the engine as soon as the message is displayed, so have never had a chance to listen for nasty noises. Sounds nice when the message is not displayed.

What do you think about their comment that the wrong liquid gasket was used between the intermediate section and the upper block? This looks like a VERY big job.

At the suggestion of another member I am about to remove the oil cooler and clean it.

I now remember having a very similar problem on the engine in my boat which I traced to a blockage (bits of rubber impeller from water pump) in the water jacket of the oil cooler so the oil just got hotter and hotter.

[alanjackson2011]

Well - I took off the oil cooler and there was no blockage in oil or water.
I think I have tried almost everything now but still have the problem.

To re-cap. Oil warning message comes on after 3 miles saying NO OIL PRESSURE STOP.

Engine sounds good when cold, not at all noisy, purrs nicelky.

I had the oil pressure cheched by tyhe Volvo dealer who confirmed cold prerssure was 30lpsi and nothing after 3 miles.

Using fully synthetic 5W30 oil.

All sump O-Rings replaced and a lot of sludge removed. Square drain holes back into sump werre totally blocked. No different.

Oil coller removed and checked - bo blockage.

Is it possible the water is not being pumped through the oil cooler? It flow through it but I am not sure if it is being pumped through under pressure.

Anyone know wher these pipes start from? I can see the oil cooler end but can't see where the other end goes to. I did have a very similar problem on my boat where the water was not pumped through to oil cooler.

I am now desparate and out of ideas. Any suggestions would be most welcome, Thanks everybody for the help so far.

[precopster]

I was having as think about this and following this thread. At least by having pressures confirmed at the dealer you KNOW it's not the oil pressure switch. The worrying bit for me is that you say that the intermediary gasket is a non-genuine (pink) one. Are you aware that this is actually the bearing cap for the crank?

In saying so you may be dealing with possible previous bad assembly of crank and/or rod bearings which can affect oil pressure.

Can you find out from any previous history what exactly was done and who did the work?

Also before embarking on the previous route I would be pulling the oil pump to inspect the inner workings and the pressure relief valve. It's not a huge job if you have an impact wrench for the 30mm crank nut and some torx drivers for the front mounted bolts and a good 4mm allen for the rear mounted bolts.

[alanjackson2011]

Many thanks for your prompt reply, I bought this car with a failed air-con clutch six months ago.

Previous history

154K miles VVT Hub replace, plus cam belt kit. (Main Volvo dealer)

165K miles Oil leaks. Breather system stripped out and replaced. Cam seals and oil pump seals replaced. New VVT Hub belt. Rear mail bearing leak – added Wynns StopLeak.

171588 miles. Remove gearbox and fit rear mail oil seal.

Last two jobs carried out by an independent Volvo garage.

179K I bought the car supposedly with only a bad air-con clutch, I had replaced by a local garage with a used unit.
Climate control panel was also dead – I replace this myself with one from Ebay.

Started car drove 3 miles NO OIL PRESSURE message appeared.
Tested by Volvo confirmed it drops to zero when warm. They commented on the black sealer above the intermediate unit.

I removed the sump and lots of sludge removed, all O-rings and seals replaced with kit from Volvo. Still the same.
Oil cooler removed and checked for obstructions. None found.

When I called into the garage that was fitting the used compressor I noticed they were yanking some pipes around to get the old compressor out, which makes me wonder if they collasped a pipe supplying water to the oil cooler.
I am wondering if I can measure oil temperature.

I really appreciate you help, thanks

[precopster]

Nothing there in the history stating the crank was pulled or bearings replaced (if it were it would be a rarity for this mileage).

Just so we haven't crossed wires here are you saying that the next seal upwards from the sump is a black sealer?

Interestingly my wife's '95 850 also has black sealer at this union (too much of it) and is on the original engine at 82K miles with no history of having the crank/bearings pulled. Perhaps Volvo's been testing different sealers during production in various years??

Feel the pipes carrying coolant to the oil cooler and run your hand along their length. Are there any sections which feel softer/collapse with pressure?

You can find a digital multimemter made by UNI-T (model is UT33C) which comes packaged with a temperature probe. Cost is all of $15-$20. This would be easier than purchasing a specific guage and can be re-used for measuring voltage/current etc. You could screw the probe wire to a oil cooler bolt under a washer and take live readings.

[alanjackson2011]

Hello again, yes the joint with the black sealer is the next one up from the oil pan joint.

The pipes from the oil cooler are rubber for about 9 inches then metal, which disapear up behind the engine.

Thanks for the suggestion about the meter - I will see if I can get one.

I will have a hunt around the forums to see what the temperature should be, Thanks again, Alan

[J5T]

I still believe that you could have worn crank components causing your low oil PSI issues. I say this based on the sludge, plugged square hole, etc.

I know that you are at the end of the rope here and it may call for another engine. I know, fargen Ouch! Whether coolant is being supplied to the oil cooler in this case does not matter. If no coolant was in the oil cooler you would still get pressure after 3 miles.

I would now go the route of the oil pump like precopster said. However, I would just replace the oil pump as a unit. It is fairly easy to get out if you have some mechanic skills. I am thinking that you have a worn or damaged oil pressure relief valve that just cannot hold the pressure once warm and/or the pump housing and pump gears are worn to the point that the leakage is too great to hold pressure. There are a lot of sludgy miles on this vehicle. I believe that the oil pump has seen some damage, but I am looking at this from 8000 miles away. I have seen many oil pumps being a pump engineer in a previous life and this is where I would start.

If you are going to do the pump yourself, you will need a tool to get the oil pump crank seal over the crankshaft. Glück.

[alanjackson2011]

Many thanks, I shall have to try the pump - I don't seem to have much else left.

Replacement pumps do seem to be very expensive, but probably worth the gamble.

I held off because it seems like a big job with the timining belt etc. and other post said they had never heard of a bad V70 oil pump.

At least it is less trouble than removing the intermediate section which is what Volvo wanted to do at vast expense, Alan

[alanjackson2011]

Thanks J5T. It would be nice to just fit a new pump, but they are over £200.

I am thinking that I am flogging a dead horse, and don't want to risk throwing away another 200 plus pounds'

I will take it off as you and Precopster suggest and see if I can get it checked, or see anything obvious.