Please don't be the head gasket...!

larfinboy

New Member
Hi all. I have a slow coolant leak, so far I have had to put around 300 to 400ml of fresh coolant in since the end of the summer holidays. I have also serviced the van my self around a month ago, fresh oil ect. Today I checked the oil and have noticed a creamy substance under the oil cap. I'm thinking I have coolant getting in the engine, but I have not noticed any white smoke yet or drastic drops in coolant level / engine over heating. Is this a blown head gasket? If so does any one have a rough minimum guess i'll need to pay for this? Timing belt is also due a change next year, so im thinking I could get both done at the same time? Whats your thoughts? Many thanks for any help you can provide.
 
Head gasket wouldnt be so bad.

Failing EGR more likely.
So would EGR cause the creamy substance under the oil cap? I've done a very quick google searce and the only current symptom is the engine management light on. Its always drunk diesel like a fish and no worse than normal, no rough idle, no fumes, no lack of power, and i havn't noticed an unusual knocking noise (yet...!) Many thanks for your input.
 
Emulsification in the oil filler neck is regarded as normal by VW on some engines, have a Search and you’ll find some content. I just think it’s the result of a piss poor design; the oil filler much being higher than the PCV and being so long it is cooler than dew point.
If the oil on your dip stick is emulsified then that is a serious matter.
 
So would EGR cause the creamy substance under the oil cap? I've done a very quick google searce and the only current symptom is the engine management light on. Its always drunk diesel like a fish and no worse than normal, no rough idle, no fumes, no lack of power, and i havn't noticed an unusual knocking noise (yet...!) Many thanks for your input.

Sounds like a head gasket tbh. Can get a test kit to see if you have hydrocarbons in the cooling water. Which would maybe also indicate similar issue. There are many wiser sages on here than me though. Good luck.
 
Emulsification in the oil filler neck is regarded as normal by VW on some engines, have a Search and you’ll find some content. I just think it’s the result of a piss poor design; the oil filler much being higher than the PCV and being so long it is cooler than dew point.
If the oil on your dip stick is emulsified then that is a serious matter.
So should I just leave for now until I notice anything else wrong and just top up the coolant again? Or take it to a garage and let them have a butchers?
 
If you are adding coolant there is a serious issue providing it is not an external leak.
You run the risk of contaminating the engine oil and destroying the engine, probably the turbocharger / s first. Worst case the engine hydrolocks when you come to start it and that’s a new short block unless you are doing the labour yourself.
No coolant leak gets better by itself.
A workshop needs to check that the water pump drain isn’t discharging coolant, that there is no hydrocarbon trace in the coolant and finally a static pressure drop test both hot and cold over a long period and allow for settling.
You haven’t mentioned which engine / gearbox you have but there is the possibility for 3x liquid cooled units to fail.
Most likely the EGR, often only when hot, probably best to remove and test though, if it has more than 45-50K miles on it just renew as it will likely be severely fouled with carbon anyway.
Charge air cooler, you may have one if your engine doesn’t have an air cooled intercooler with the rest of the radiators.
DSG gearbox oil cooler, obviously you only have one of these if it’s an automatic. Fairly rare to fail but game over for the gearbox if the gear oil is contaminated.
 
Some mayo in the filter cap is normal.

Sounds like the EGR leaking to me...... Very common issue.

Head gasket is very uncommon.....unless a secondary effect after catastrophic over heating.

You can do a sniff test to see us you have combustion gasses in the coolant.

The garage will pressure test the cooling system and use a boroscope to see if it drips in the EGR intake path.

You can check the oil to see if the level is rising, or going milky color.



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More info...




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Just be aware, when using a 'sniff tester' - head gasket test, that if the EGR valve is cracked / leaking, that you could be getting exhaust gases mixing that way - which would give a positive head gasket fail result with the tester, even if it has not failed. \

Easiest check for an EGR issue, is to remove the front EGR pipe onto the cooler and check for pink residue, by dipping a cable tie into the EGR cooler end.
 
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