Jetta 5 2.0 oil cap condensation

[Jetta5 man]

Hi guys I need advice or info.i have a 2.0jetta 5 non turbo2009 model.i have noticed mayonnaise on the oil cap but not on the dip stick.some mechanics tolde this is normal especially on these cars with this engine type to experience this issue.i took it a radadiotr place to test with that blue liquid that fill in tube and put it in where the water and coolent goes if changes colour that means head gasket if it does not change probably not.amd mine did not change any colour remained blue.any one experienced the same issue

[NH 9821]

Oil cooler?

[Jetta5 man]

I dnt know where does that sit.does it mean that that test I did came back negative does it mean I dnt have a blown head gasket

[chucker02]

I have seen other citis and even a jetta 5 that also had some mayo on the oil cap. Nothing to worry about. You can start to worry when you see it on the dipstick, but if the car behaves normally and does not get hot then I wouldnt worry about it. Remember that the engine breaths into the tappet cover and it can cause a little condensation as the 'gasses' are hot.

[missioner]

Heat exchanger starting to seep.

It's the aluminium block on the oil filter housing, sandwiched between the oil filter and the block. It has 2 water pipes attached to it.

Do an oil change as part of the job, as well as a full cooling system flush. Not changing the antifreeze every so often is part of the cause, after a while antifreeze becomes corrosive and eats away the soft parts like plastic and aluminum.

[Jetta5 man]

Thanks for the info.but do I think the test I did at the radiotor place either liquid not changing colour how conclusive is that test

[Jueshen]

that test only tests for presence of exhaust gasses in coolant (blown HG), the test is quite accurate
if you HG is blown you may have other symptoms, coolant boiling, car overheating, loss of coolant are just some of them
you have another issue possibly

[Jetta5 man]

Thanks but I would take any issue thana blown head gasket.but speaking to few. Guys who have had similar issue said that I should use shell helix instead of GTX as GTX can cause this issue.also spoke to be be mechanix told the way the breather system is designed causes this issue.he told me that if the exhaust gas test came back negative which it did then dnt really to be concerned

[bru-tom]

i removed my heat exchanger all together and made a copper fitting to reroute the water-flow that originally ran through it. These exchangers are meant for the colder climates.

However, i never experienced any oil residue on my oil cap, but my entire cooling system had a massive sludge build up from the oil mixing with the water.... so i had to flush the system over and over and still, a year later, there is still some sludge floating to the top of the water bottle. not sure if this is your issue though. The water never mixed with the oil thankfully, im putting that down to the fluid pressures involved...

[NH 9821]

Sorry they call it heat exchanger.

I just changed the oil cooler on my merc. Similar thing. Seals give up. Oil mixes in coolant system but not engine side.