Friend of mine has a diesel turbo van, one day it just blew all the oil out of the RADIATOR! Head removed and skimmed, new head gasket, 4 miles down the road, same thing.

It's a Merc Sprinter. I thought it might be the liquid cooled oil cooler because that's one of the places where oil and water pass each other, but that's fine.

Any ideas?

Originally Posted by Zanx

Friend of mine has a diesel turbo van, one day it just blew all the oil out of the RADIATOR! Head removed and skimmed, new head gasket, 4 miles down the road, same thing.

It's a Merc Sprinter. I thought it might be the liquid cooled oil cooler because that's one of the places where oil and water pass each other, but that's fine.

Any ideas?

Try finding a Merc Ambler Sprinter in a scrapyard that's got an engine without a knackered head gasket...

Got a mate with one and from what he's said they have a fair bit of head gasket problems.

His old blue bus (Merc 208 ) which has a fairly similar engine as far as I know was a lot better van.

Originally Posted by demographic

Try finding a Merc Ambler Sprinter in a scrapyard that's got an engine without a knackered head gasket...

Got a mate with one and from what he's said they have a fair bit of head gasket problems.

His old blue bus (Merc 208 ) which has a fairly similar engine as far as I know was a lot better van.

Yebbut, if it's just had a new head gasket, it should have managed 4 miles without blowing again.

Just seems like a bizarre fault. Presumably there's a place on the engine where oil pressure can jump into the cooling system and make a break for freedom.

It sounds like "take the head off again, clean relevant areas and look for the cause, resolve the cause and re-assemble"

Could there be a blockage in the oilway in the head?

Originally Posted by millard

My BMW F800S has a heat exchanger, a wee box down the front of the engine where the coolant and oil pass thorough. Has the Merc got one? is it damaged? leaking?

That'll be the liquid cooled oil cooler.

Originally Posted by big bald one

Probably way out but some turbos are watercooled, could it be in that area.

It is the radiator, not intercooler throwing oil?

Yep, like Vesuvius, rev the engine, there's a slight delay, then it spews out. Not much air though, no foam, no bubbles.

Originally Posted by DanDangerous

Is the water pump/cooling system working? If it isn't, running the engine up, then driving it for 4 miles could cause it to overheat again. Whether it's long enough to warp the head or not is questionable though I guess.

When the head was skimmed did you measure that it was flat? I saw a dolly sprint head once that was skimmed, it was still warped like a banana* - presumably it was bolted down/put under tension before it was skimmed which flattened it out.

*Slight exaggeration.

If it had overheated, then the gauge would have shown it and there would have been steam and water all over the place.

Originally Posted by DanDangerous

Fair enough, it's probably working ok then.

Just out of interest are the water and oil pumps on the same shaft/combined? That's something I've seen before (can't for the life of me remember what on though) and if the gaskets/o rings between the two parts of the pump fail it gives similar symptoms to a head gasket failure.

That's kind of what I was thinking just now. It's obvious that high pressure oil is making it into the cooling system, and not just a bit, all of it!! No water in the oil, just oil in the water.

remove the thermostat and check it using the kettle (while the missus is out)

had something similar happen on my old 99turbo, that was the waterway in the block corroded through into the oilway, except water pressure is far greater than oil pressure and i ended up with a sump full of water.
my money is on turbo seal