No oil pressure!!! Please help

[slowtwitch]

Hi I'm new to this forum, and I hope it isn't an issue to post this new thread.

I've seen others have had similar problems as I and have read the threads already, but I'm DESPERATE :(:(:(

Here's the details:

2001 2.4XC70 Volvo with 210 000km (I do not know the full history of the car, bought last year with so call no prior issues). The problem is loss of oil pressure. My mechanic has done the following:
NO OIL Pressure Warning light -
1) Clean sludge from oil pan and clean oil strainer 1yr ago (warning lights did not come on again for 1 month then)

NO OIL Pressure Warning Light

2)Replaced oil pump approx 9months ago (we do not use the vehicle that much and the oil pressure warning light did not come on for some time)

NO OIL Pressure Warning Light

3) Replace head gasket and redo engin head at engineering works, new water pump and radiator was also done previously(head was pitted and was losing water-although not related to oil problem)

4) Replace main bearings and redo crankshaft at engineering works (same time as #3)

Mechanic reports it is still losing pressure when reaching operating temprature
Although piston sleeves did have minor ridges, nothing serious and mechanic did not feel it's needed to resleeve/ redo the engin block. (sorry for non-tech discription).

5) Let Volvo dealership do a diagnostics - complete waste of time. Their only solution is to a) replace oil pump or b) replace complete engin!

What is there that we overlooked. From an internet search it seems like the only other items are:

- Relieve Valve replace/ check/ clean
- Ensure all o-rings (is it 7? in total) are replaced in oil pan and seated properly, although some, if not all, were obviously replaced with the main bearing replacement
- Oil pickup tube replace (the tube was cleaned already)

Your assistence will be greatly appreciated since we are at an dead end :confused::confused::confused:.

[slowtwitch]

Another search and I found 2 more things to check:


The cause of this could be a plugged breather system or the oil trap, most after market shops are not familiar with this system

Do you guys agree?
What about the oil trap could be the issue?

[billr99]

I don't see anywhere here where you have checked the most obvious. Have you checked to see if the oil pressure sensor and its circuit are good?

Good luck,

Bill

[Astro14]

Oil trap wouldn't cause the warning light to come on. It causes leaks when it fails, that's about it...

The warning light comes on when there is no oil pressure, well, actually pressure below about 4 PSI (severe engine damage is happening at that point, unless the engine is at idle...).

From your description, the mechanic has verified that the light works (as pointed out abve, it could be a false indication), but that's step 1 - verify that the light is valid.

There is usually a pressure bypass spring - I don't know if this engine has one, most do, but I've not taken this one apart yet, so, assuming everything else was done correctly - it sounds like that bypass spring broke, and you're getting a pressure drop.

You've spent a lot on this car - the engine is basically rebuilt, but operating it with less than 4 PSI (if that's valid) will destroy it...don't drive it, have the mechanic verify the pressure. Personally, I would replace the oil pressure switch (or sender, as it's sometimes called), then pull the pan again, verify that the pick-up isn't clogged again (sludge is common, and while it should have been cleaned during the rebuild, that pick-up is suspect), and replace the bypass spring.

[MacNoob]

Please verify that the engine is *actually* low on oil pressure - should have been step #1 - put a known good oil pressure gauge on the engine and see what the pressure really is - don't believe the light. If oil pressure is low enough for the light to come on, you should be able to HEAR that something isn't right - all kinds of clattering noises etc.

[slowtwitch]

Sorry for not stating the obvious, yes we are not relying on the oil pressure switch/ sensor, the engin IS losing pressure (not sure what the reading is, but it's losing way too much pressure)

Thanx Astro, it's the first time I hear of an issue with this bypass spring, will check it out aswell

[billr99]

Sorry for not stating the obvious, yes we are not relying on the oil pressure switch/ sensor, the engin IS losing pressure (not sure what the reading is, but it's losing way too much pressure)

Thanx Astro, it's the first time I hear of an issue with this bypass spring, will check it out aswell

So an actual pressure gage has been attached to read pressure directly off the oil galleries? What doesn't make sense to me is that you have done the usual fixes for low pressure. It also does not make sense that after your fixes you have pressure then you lose it again. It strikes me as not a mechanical issue but an electrics one. These cars have such a botched up monitoring system, I would still think that a through check of the sensors and wiring might be in order.

Anything else I can think of (like a porous casting or leaking gallery plugs) would produce low pressure, period. It wouldn't come back, then go away again. Please keep us posted on this one. I'll be interested in hearing what the answer is when you find it.

Good luck,

Bill

[slowtwitch]

Yip using a guage to measure the preasure, but as I said the mech has the numbers, he just told me it's losing at least 50% and it even drops to zero.

just coming back to this bypass spring, what spring is it and where does it sit?

[cattlecar]

The bypass or relief valve is part of the oil pump and would be new with the replaced oil pump.
I don't have good news for you.
I have worked on several of these engines that were sludgy, and then had all the things you mentioned were done and it still had poor or no oil pressure when hot.
Some were fixed with new oil coolers. The sludge you found also passed through that oil pan mounted oil cooler. It is before the oil pressure feed to bearings and the oil pressure switch port.
Some of these had main bearing wear with no lower end knocking, you have already replaced main bearings and had crankshaft repaired (I assume).

A couple had the engine thoroughly examined and all things not correct repaired and then it was re-assembled and had poor oil pressure and was then replaced.
Your dealer may have been down that path and said engine replacement for that reason.

[slowtwitch]

Are you suggesting it could be oil cooler that can be replaced, or does it sound like a new motor to you?

[slowtwitch]

Ok so same time we're discussing the oil cooler here, my mechanic discuss the oil cooler with some other mech - He'll remove oil cooler and have checked out.

Will keep you posted

My mech hasn't given up on this motor yet and remains positive we'll find the fault

[PierreC]

Ok so same time we're discussing the oil cooler here, my mechanic discuss the oil cooler with some other mech - He'll remove oil cooler and have checked out.

Will keep you posted

My mech hasn't given up on this motor yet and remains positive we'll find the fault

slowtwitch - Where in SA are you? PM me ...

[slowtwitch]

Update: Oil cooler removed and cleaned in acid bath and reinstated - made no difference.

Sump removed (AGAIN!!!) o-rings replaced (AGAIN!!!), still losing preassure on guage

Pierre's contact recon we should check out the cylender head/ cam shaft interface, it could loose pressure where the shaft enters the cylinder head

In the meantime we're stripping the motor to check the block

[Allen]

New car.

[slowtwitch]

Ok so I have good news and bad news.

Good news is I think we've solved the mistery. My mechanic spoke to Pierre's contact and both are in agreement that my pressure loss is between the cam shaft and head (from visible evedence that my mech didn't previously think was a problem - he's done other non-volvo engins which were even worse without a prob).

Bad news is I need a new engin at $6000 approx, or reconditioned engin at $3K or second hand Japenese import at $2k approx (with the assosiated risk of using someone else's old motor).

So I have to fit the bill of the repairs sofar (my mech is accomodating regarding labour costs) plus new/other engin plus fitment

phew, I've heard horror stories of people having car problems like this, but this is a first for me

[Astro14]

I would not spend $6K on this: 2001 2.4XC70 Volvo with 210 000km

You can get another one for about the same...or less...

I might spend $2K on it...but once you hit the threshold of 1/2 car's value, a repair becomes a difficult expense to justify...

[slowtwitch]

Yes, agreed. In South Africa my model is now worth approx $8-8.5k. When I bought it, I got it at a real bargain, but I'm afraid the previous owner forgot to disclose some sure issues he must have been aware of before selling. Even with the issues I've had, it is still a great vehicle (no need to convince anyone on this forum) and after the transplant, I'll prob keep it for years still

[Astro14]

Different market then...

Here's an anecdote that you may find germane: My sister in law had a Nissan Pathfinder about 8 years ago - and while she was still making payments on it, at 55,000 miles, it had a piston break (!). The dealership rebuilt it - she wondered if she should keep it, how well would the engine last with a rebuild by a dealer mechanic? I told her that if the rest of the vehicle was sound, it was worth getting fixed...and sure was better than having to buy a new car while taking a huge loss on this...

Her Pathfinder just turned 270,000 miles...

So, my point: if the rest of the vehicle is sound, that factors into the equation...

[Allen]

Just dump a quart of Lucas into the oil and forget about it.

[slowtwitch]

Just a update, yes it is two months later!!!

The vehicle is still not sorted, however the following has been happening:

We think we found the problem - cam shaft entering the head, apparently the tollerences here are much tighter than most other engines. So as confirmed by a few different sources, the engine needs to be replaced.

My options were
1) New engine - not worth the money considering the total value of the vehicle
2) Recon engine - available but also pricy and not avail in my city (so transport costs and my engine needs to go to them also etc)
3) "low milage" import engine from Japan. cheapest option ($2000) and according to various sources, worth it! But finding the right engine was really a pain! This is not a Toyota or something which everybody carry stock of!!!

For a 2002 XC70 2.4T it is a B5422T3. not a B5422T or anything similar. O yes and it needs to be a unit that has a 5 coil pack, not a distributor!!!

So eventually I found the right engine (which is available and not still on some ship in the middle of the Pacific)

So currently my mech is installing the engine (hopefully - unfortunelty he is not a fast mover, as you may have picked up by now) and I'll give feedback soon.

PS My mech as very accomodating - we settled the bill of ALL COSTS to Date excl new engine and installation and bill came to...
wait for it
$400!!! He did not charge me any labour, only parts and engineering works (which also seamed too cheap, but I'm not complaining)

[Astro14]

I understand that you are going with a new/used engine...but the rationale...the camshaft tolerances?!? I am really struggling to understand that one... it makes no sense...

[slowtwitch]

The way I understand it, my mech did pick up that where the cam shaft enters the head there was signs of bit of oil seepage. However, he's done alot of engines (not volvo but mainly merc's) and many of them showed more "leaking" which did not cuase any oil pressure problems. But when he spoke to a local volvo expert, and going through all the things he's done and checked for, the expert asked him about the cam shaft/ head interface/ play/ tollerence, having had quit a few volvo engines replaced due to similar problems. The conclusion was that that is most likely my problem and I need a new head, but I was advised by various sources that if you need to replace the head, you might as well replace the whole engine (not much of a price difference).

The advantage off course now is that I can strip off all the parts from my old engine like turbo, starter motor, oil pump etc. and keep as spares

[slowtwitch]

Happy days are here again....

I'm picking up me Volvo TODAY!!!!!

So let's see

[Allen]

I wonder if the oil filter canister is filled with sludge?

[slowtwitch]

Well she's back in my garage and our family feels complete again.

I've forgotten just how much I like this vehicle. There are just so many practical features that makes the xc70 a winner

PS And it helps if she purs like a kitten

[Allen]

XC70 is a fantastic automobile. Sorry you had to go through all of this.