P38A Head gasket advice needed

So this concerns my green 1999 p38 with 4l V8. It has been sat for 8 years before I acquired it.

I just did some major service work and found a considerable amount of milk in de oil filler cap. Also tiny tiny bit in the drained oil. After changing oil and running the engine visible condensation droplets in oil filler cap. Coolant level is low (only just in the expansion tank), but the drain plug was leaking a bit. No signs of oil in the coolant (eg. milk, black line in reservoir, black traces in coolant).

At first it seems to me that I have a coolant-oil gallery head gasket leak. However I find it strange that the contamination is only in one direction (coolant towards oil).

I don't know how what the heads look like on this engine. Is it possible to have an oil-coolant gallery leak on these or are they not adjacent?

Any other places where coolant could leak into the oil.?

On this type of leak I would expect to at least see some evident in the coolant expansion tank. From a sitting vehicle I expect some condensation in the engine but the amount of milk under the filler cap seems to be too much to be condensation related

I don't really care to do the work, and the parts don't seem too expensive at first glance, but of course if it doesn't need to be done it doesn't need to be done.

Any advice will be appreciated! Also ways to test the gaskets (except for compression test which i will do tomorrow)?

1st thing is always a sniff test 2nd thing and the way I found my hg fault was to put fluro dye in the coolant then check your oil on the dip stick and see if it glows in the dark with a black light

biketeacherdave said:

1st thing is always a sniff test 2nd thing and the way I found my hg fault was to put fluro dye in the coolant then check your oil on the dip stick and see if it glows in the dark with a black light

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+1 on the florescent dye. That was the only sign on MrGorskys, that and it was clearly slowly losing coolant but no sign where until the dipstick lit up with uv droplets all over it.

Alright thanks to both of you! I've ordered some dye, should arrive tomorrow.

I will also do a compression test.

Fingers crossed!

In case I'm doing the head gaskets, any advice on which brand to use? Britpart okay for this or not? Would like to keep the cost down as it's already going to be a lot more than what I had budgeted to get the car back on the road.

Good quality ones!
FWIW I learnt a long time ago the hard way that cheapies - or even good quality non-genuine - are best avoided & usually use ones sourced from a franchised dealer.
That said, when I did the hgs on my 3.5 Classic I used Elrings which were recommended & have been fine.
I also checked the heads were flat - local specialist reconditioner - & both were very very slightly out.

Are you actually losing any coolant?
Burning petrol or diesel produces a very large quantity of water as part of the combustion process, usually seen as the liquid dripping out of the exhaust & as steam out of the exhaust in cold weather.
This will condense inside a cold engine & if the engine isn't run for long enough to get hot & boil it off will appear as mayo.
Also the reason cars used for short journeys go through exhausts faster than those for long journeys - again due to condensing inside the boxes & rotting them out from inside.

ar1g3 said:

Alright thanks to both of you! I've ordered some dye, should arrive tomorrow.

I will also do a compression test.

Fingers crossed!

In case I'm doing the head gaskets, any advice on which brand to use? Britpart okay for this or not? Would like to keep the cost down as it's already going to be a lot more than what I had budgeted to get the car back on the road.

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+ 1 Elring

Ratae said:

Good quality ones!
FWIW I learnt a long time ago the hard way that cheapies - or even good quality non-genuine - are best avoided & usually use ones sourced from a franchised dealer.
That said, when I did the hgs on my 3.5 Classic I used Elrings which were recommended & have been fine.
I also checked the heads were flat - local specialist reconditioner - & both were very very slightly out.

Are you actually losing any coolant?
Burning petrol or diesel produces a very large quantity of water as part of the combustion process, usually seen as the liquid dripping out of the exhaust & as steam out of the exhaust in cold weather.
This will condense inside a cold engine & if the engine isn't run for long enough to get hot & boil it off will appear as mayo.
Also the reason cars used for short journeys go through exhausts faster than those for long journeys - again due to condensing inside the boxes & rotting them out from inside.

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Well hard to day if I'm losing coolant as the car is off the road and has been stood for a couple if year before I bought it. Coolant is low but could also be because the drain plug is leaking.

I have done a compression test with lowest reading 145psi on cylinder 3 and highest reading of 170psi in cylinder 8. Thats 15% difference, normally thats too much. But given the age and the mileage (263k km) I am not worried. Most cylinders were around 155-160psi.

Normally the dye should arrive today so I can test the cooling system

ar1g3 said:

Well hard to day if I'm losing coolant as the car is off the road and has been stood for a couple if year before I bought it. Coolant is low but could also be because the drain plug is leaking.

I have done a compression test with lowest reading 145psi on cylinder 3 and highest reading of 170psi in cylinder 8. Thats 15% difference, normally thats too much. But given the age and the mileage (263k km) I am not worried. Most cylinders were around 155-160psi.

Normally the dye should arrive today so I can test the cooling system

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Compression test done with all plugs out and average of read attempts for each cylinder? Did compression come up with a bit of oil down the cylinder first? Can you make an adapter to connect an airline to blow air ibto the cylinder? You'll either hear a leak by inlet or exhaust if leaking past valve or possibly the water will pour out the header tank if gasket or you might hear it hissing out of dipstick or similar if blowing past the rings.

So did the test with the dye. Very difficult to tell. First thought it showed on the dipstick but when compared to new oil it looked exactly the same. I then looked in the coolant reservoir and there I see a lot of sparkles, like glitter, when i shine the UV on it. It's also in water that spilled out (didn't have cap on and water boiled, using tap water for this test). This glitter/sparkles doesn't show on the dipstick or in the oil cap. I do however again have a bit of milk and condensation in the cap. If I take the cap of there's quite a bit of water in it, I would say about 10 drops. I just changed the oil.

Difficult to do this test when you don't know what to look for. Are the sparkles/glitter what I need to look for? In that case I will just assume that the head gasket is fine, run it for half an hour with the oil cap of to allow condensation to escape and then do an oil flush and replace the oil once again. And then just assume it's fine and run the car for a bit. Unless I find the sparkles back in the oil that I drain of course.

Grrrrrr said:

Compression test done with all plugs out and average of read attempts for each cylinder? Did compression come up with a bit of oil down the cylinder first? Can you make an adapter to connect an airline to blow air ibto the cylinder? You'll either hear a leak by inlet or exhaust if leaking past valve or possibly the water will pour out the header tank if gasket or you might hear it hissing out of dipstick or similar if blowing past the rings.

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No I did it cold without adding oil. Didn't do the full procedure as I just wanted to confirm there were no major issues. I didn't expect super good values given the age and mileage.

None if what you mention is happening except for coolant pouring out of the expansion tank, but that's because it was boiling.

ar1g3 said:

So did the test with the dye. Very difficult to tell. First thought it showed on the dipstick but when compared to new oil it looked exactly the same. I then looked in the coolant reservoir and there I see a lot of sparkles, like glitter, when i shine the UV on it. It's also in water that spilled out (didn't have cap on and water boiled, using tap water for this test). This glitter/sparkles doesn't show on the dipstick or in the oil cap. I do however again have a bit of milk and condensation in the cap. If I take the cap of there's quite a bit of water in it, I would say about 10 drops. I just changed the oil.

Difficult to do this test when you don't know what to look for. Are the sparkles/glitter what I need to look for? In that case I will just assume that the head gasket is fine, run it for half an hour with the oil cap of to allow condensation to escape and then do an oil flush and replace the oil once again. And then just assume it's fine and run the car for a bit. Unless I find the sparkles back in the oil that I drain of course.


No I did it cold without adding oil. Didn't do the full procedure as I just wanted to confirm there were no major issues. I didn't expect super good values given the age and mileage.

Bone if what you mention is happening except for coolant pouring out of the expansion tank, but that's because it was boiling.

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Sounds like condensation to me.

Datatek said:

Sounds like condensation to me.

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I will drain a bit of oil tomorrow with cold engine. If any water is in the oil it should come out then, and I can verify that no dye from the coolant is in it. Fingers crossed

I can't remember the brand but one of the things that people put into the coolant system to block up leaks has exactly what you describes as 'glitter/sparkles' in it.
I think it's to help it block up any holes.
Some just put it in as a 'just in case' even if they don't have coolant loss.
Not a fan of any of them as I doubt they're going to do much to keep the smaller passages in the cooling system unblocked - but I do accept they might be the only alternative as a 'get you home' bodge.

I would suggest getting the car up & running & in normal use & keep an eye on your coolant levels.
A pressure test would be a good idea to see if the pressure drops without any apparent leaks - did this on my Classic using one of the Mityvac type devices ( does vacuum & pressure) & it showed up a slight weep from a hose joint which was solved by nipping up the hoseclip.

The UV dye lights up under a UV torch like an 80s disco. If none on the dip-stick then that's positive. All v8s doing short journeys get a bit of condensation on the filler cap. I wouldn't sweat it. Check for UV by your left foot on the transmission tunnel inside. That's where the heater matrix tends to leak and the infamous o-rings.

Check the radiator too and where the cookant hoses clamp on.

Thanks for the tips guys! Drained a tiny bit of oil and no traces of the dye so I flushed the cooling system and will now flush the oil system and continue with my maintenance works.

I will of course keep monitoring when I start driving the car.

Alright, I replaced rocker cover gaskets and did a whole bunch of other works. Today was the time of filling with coolant again and then doing an oil flush. During warming up I managed to pour 6 L of coolant into the system. However when it got up to temperature it started boiling over. I was immediately thinking if the head gaskets, however revving the engine does not i fluence the boiling over, which I would expect with a blown head gasket.

I did completely flush the coolant system:drained, flushed with tap water and blown out. I would have expected to be able to pour more than 6l in. Is the boiling over part of the purging of the system? Engine temperature was also going into the red. Coolant reservoir was steaming which I wouldn't expect with proper coolant.

So I think I either have an air lock or I need new head gaskets. Any ideas?

If you've got leak stop in the system.. the sparkles.. you need to flush it out, it's ok as a short term 'get me home' if it works, but will cause pain in the longer term and block passageways

If you follow the procedure, you shouldn't have much problem. But, you need to check all the narrow hoses for blockages. The bleed return also needs to be clear of coolant for the bleed process

As you're filling the system, it helps to put a finger over the bleed return hole in the filler neck, then squeeze the top hose a few times, then fill a bit more

If you remove the small return pipe at the top of the rad you should see a solid stream of coolant coming out. No burping or spitting. Rev the engine to 3 or 4000 rpm and check for that solid stream. I had a bit of trouble refilling my system last week so drove the front onto ramps to get the rad at the highest point. Not sure if that helped but all good now.

On the head gasket, assuming you can get the cooling working, l would drive it for a bit and check coolant level and oil appearance after each drive.

ar1g3 said:

Alright, I replaced rocker cover gaskets and did a whole bunch of other works. Today was the time of filling with coolant again and then doing an oil flush. During warming up I managed to pour 6 L of coolant into the system. However when it got up to temperature it started boiling over. I was immediately thinking if the head gaskets, however revving the engine does not i fluence the boiling over, which I would expect with a blown head gasket.

I did completely flush the coolant system:drained, flushed with tap water and blown out. I would have expected to be able to pour more than 6l in. Is the boiling over part of the purging of the system? Engine temperature was also going into the red. Coolant reservoir was steaming which I wouldn't expect with proper coolant.

So I think I either have an air lock or I need new head gaskets. Any ideas?

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Sounds like an airlock to me. Park it pointing uphill if possible and leave the expansion cap off revving to 2000 rpm but keep an eye through the gap at the bottom of the bonnet for it burping over. If someone can squeeze the pipes while filling then so much tbe better. The v8 can be a total sod to get air out after coolant has been emptied.