Faulty oil cooler coil can appear to be head gasket problem?

[Laney760]

I've just read this on a thread about blown head gasket on D24TIC that is posted in 700/900 series and not in this diesel section.

Quote:
Sometimes these were diagnosed as having headgasket problems due to water being in the oil and vice versa, when it was actually the oil cooler coil which used to fracture inside the radiator and allow the fluids to mix when the head gaskets were actually fine, quite a common fault I am told. I know of a garage that stripped and rebuilt a V6 760 engine a few years ago (when it was economically viable!) complete with head gaskets, and cylinder liner seals, only to find that when they rebuilt it and started it up, the problem persisted. The car was susequently sold as scrap for a tenner to someone who new about the problem, and he fixed it with a new radiator!

I will point this out to the garage who are diagnosing my coolant usage suspected h-gasket problem next week but need to make sure I know what I'm talking about. Another member has taught me where my oil cooler is on my D24TIC (not in the rad) so is this yet another oil cooler inside the rad? If the answer to this is 'yes', does the fact I have an obviously new rad on mine mean I can rule out this possibility? Many thanks

[craig8661]

i did say in one of my posts look at oil cooler i had a vw bora and aparantly digging back into vw history it was known for the cooler to weep oil into the water the cooler is £30 at most but is yours intercooled or direct turbo if its direct turbo you will see a square piece of metal abouve the oil filter with water hose in and out

[Laney760]

i did say in one of my posts look at oil cooler i had a vw bora and aparantly digging back into vw history it was known for the cooler to weep oil into the water the cooler is £30 at most but is yours intercooled or direct turbo if its direct turbo you will see a square piece of metal abouve the oil filter with water hose in and out


This thread is talking about ANOTHER oil cooler inside the rad Craig, not the one we were on about or is that particular thread nonsense?

[craig8661]

this engine was a intercooled one see pipe over top of engine into inlet manifold theese engines had a oil cooler under the rad
http://i19.photobucket.com/albums/b165/mistonia/volvo%20crap/25052008023.jpg

this engine is a non intercooled one with a water cooled oil cooler
http://i19.photobucket.com/albums/b165/mistonia/volvo%20crap/d24tengine.jpg

[craig8661]

as far as i kno the only rad is the one under the rad on these none in water rad thats only on petrol auto ones

[Laney760]

I did wonder if they were confused and on about a petrol one, the actual thread was about D24TIC head gasket and this was one response, will wait and see if I get any more responses here. Have to say my engine is SO squeaky clean and shiny compared to your photo of intercooled one apart from I recently got some black blowback staining rear right of mine, dunno if diesel or oil. The mechanic today reiterated what I have suspected about my engine all along, at some stage it's had some major work done to it, he wonders if camshaft.. Downloading some pics of mine to my album

[craig8661]

lol the intercooled engine is the top one and had 230,000 miles on her and only had one small oil leak on the back cam pully or rocker around there the bottem engine had less than half the milage and looked very worn
the top engine is now being rebuilt new sump and cheacking then its going into a auto volvo 940 with a worn engine
the top engine the water pump pully snapped on it when it was 3 years old had new head pully etc as it dropped the cam belt and smashed the valves up

this was the non intercooled one i sold on ebay as you can see the oil cooler abouve the filter
http://i19.photobucket.com/albums/b165/mistonia/volvo%20crap/volvod24nonintercoold.jpg

[Laney760]

Any idea how much an intercooled engine weighs? Would a second hand intercooled engine physically fit into a 940 estate? Often see ones for sale and wonder if my car is physically capable of fetching it home (my suspension is very good). Expect I'll get a lol from you and maybe a definite no on this, lol....

[Peter Milnes]

Someone is being confused re oil coolers. The one under the radiator is for diesel engine oil (D24TIC). The one in the radiator is for petrol and diesel with automatic gearboxes. The one that can get confused with head gasket trouble is the gearbox oil cooler in the radiator. A new looking radiator is no guarantee of it's goodness.

All the best, Peter.:car-smiley-031:

[volvo-express]

I have bought a 1991 diesel 940 lately and I thought wrongly that it was the oil cooler. But after flushing all of the cooling system there is oil still coming through so looks like I will have to replace the head gasket.

So while the head is off im thinkin of doin some work to the head, the car has done 119k miles and prob dosen't need work but im going to do it as the car is coming upto 20 yrs old.

So I will be stripping the head "acid", regrinding the valves, new oil valve stem seals, cam seals....

After doing some research there are different head gaskets for the D24,
- metal gasket
- 1/2/3 notch gasket

Whats the difference between them?

[jor]

The thicknesses are 1.4, 1.5 and 1.6 for the 1,2 and 3 notch gaskets. The ones supplied by volvo are 3 notch. The purpose of having different gaskets was to compensate for differing piston heights, so to use the 'correct' one you would have to be able to measure piston height.
If you have a read of the December posts on the tufts elist for the d24 you will find a chap who has had trouble after a rebuild. You can see the lengths he went to in order to get it done right from the pictures
(http://i1004.photobucket.com/albums/af168/vwjunkie53/volvo/102_2661.jpg)
but although it runs well once started it is difficult to start from cold, suspected to be low compression due to ... the valve job.
Anyway it may be worth your while having a read, or even asking for advice.
People have compensated for inability to get 1 and 2 notch steel gaskets by removing the bottom layer of the 4 that go to make it up.

jor

[volvo-express]

The thicknesses are 1.4, 1.5 and 1.6 for the 1,2 and 3 notch gaskets. The ones supplied by volvo are 3 notch. The purpose of having different gaskets was to compensate for differing piston heights, so to use the 'correct' one you would have to be able to measure piston height.
If you have a read of the December posts on the tufts elist for the d24 you will find a chap who has had trouble after a rebuild. You can see the lengths he went to in order to get it done right from the pictures
(http://i1004.photobucket.com/albums/af168/vwjunkie53/volvo/102_2661.jpg)
but although it runs well once started it is difficult to start from cold, suspected to be low compression due to ... the valve job.
Anyway it may be worth your while having a read, or even asking for advice.
People have compensated for inability to get 1 and 2 notch steel gaskets by removing the bottom layer of the 4 that go to make it up.

jor

Jor,

Thanks for replying, I managed to get the head off the car today and i have a good idea where the oil was starting to mix with the coolant with the making on the gasket. The gasket that was on the car was a 3 notch so it is a volvo one.
When the guy at the garage seen the gasket he said that the head was skimmed 3 times hense the 3 notches - I was a bit deflated when he told me this. But what what you say about the notches, there maybe lots of life in it yet.

Is there a way i can get a micrometer to the head to see if the head has ever been skimmed - if so what is the orignal thickness of the head so i can compare.

Thanks volvo-express

[volvo-express]

I have been on the internet trying to find out about the SS gaskets and the part number but found confirmation of the notch sise's.

http://www.oldsouthoffroad.com/volvo/SB21-935-0296.pdf

[jor]

Does this mean that the hg needs to be replaced? I don't know how to tell if a head has been skimmed, but if it is plane rather than having it skimmed perhaps you could remove the bottom layer of the hg, i.e. skim the gasket rather than the head.
Looking forward to hearing how you get on.

jor

[volvo-express]

Does this mean that the hg needs to be replaced? I don't know how to tell if a head has been skimmed, but if it is plane rather than having it skimmed perhaps you could remove the bottom layer of the hg, i.e. skim the gasket rather than the head.
Looking forward to hearing how you get on.

jor

What prompted me to take off the head on the car was the oil in the coolent system, so yes the head gasket needs replacing. I dont think the car has cooked or boiled so the head should be ok. I think im lucky that i cought it early " i let the car run for 3 hrs ticking over and no issues" I will put a straight edge on it or bring it to machine shop verify the head been flat.

Im going to write to the 2 previous owners of the car to see if the car has had the head gasket ever replaced. I must say I feel a bit more confident to hear that the notches in the gasket is got to do with the piston height rather than the head beed skimmed 3 times so hopefull the previous owners will confirm no head issues.
I will update progress or the head rebuild.