Help! Oil in coolant after head gasket replacement

[EvenM]

Hello.

I have a little nightmare with my S2 I have replaced the head gasket and after the first test drive its oil in the coolant reservoir and under minimum with oil on the dipstick.

What should I check first? Leaks around the new head gasket? Drain the oil and coolant?

Thanks

Regards

Even

[SteveH]

Hello.

I have a little nightmare with my S2 I have replaced the head gasket and after the first test drive its oil in the coolant reservoir and under minimum with oil on the dipstick.

What should I check first? Leaks around the new head gasket? Drain the oil and coolant?

Thanks

Regards

Even

Did you resurface the head when putting it back together? Why was the gasket replaced? If it was due to overheating or failure you would certainly need to check and resurface the head. I would suggest either the gasket hasn't sealed properly or you have a crack somewhere between the oil and water channels. Probably a head off and test scenario unfortunately!

[EvenM]

Did you resurface the head when putting it back together? Why was the gasket replaced? If it was due to overheating or failure you would certainly need to check and resurface the head. I would suggest either the gasket hasn't sealed properly or you have a crack somewhere between the oil and water channels. Probably a head off and test scenario unfortunately!

Thanks for quick reply. I replaced it because I had white smoke coming out of the exhaust. Did not overheat. Did not resurface the head, but is that necessary? A friend looked at the head and said it was good.

[simon20vq]

Could it be oil from when the head gasket first went? However as SteveH said the head would have needed checking first before fitting to be 100% safe

[EvenM]

Could it be oil from when the head gasket first went? However as SteveH said the head would have needed checking first before fitting to be 100% safe

I thought so too first, but under the test drive the engine used oil and there is no oil leaks, so have to go in the coolant I think

Nothing else to do then, just take of the head again and start from scratch:

Should I flush the cooling system with anything before taking everything apart?

[mike74]

If its leaking that much oil into the coolant then flushing right now probably isn't going to achieve anything. I'd get the head gasket replaced and then replace the oil & coolant. Once you're sure there isn't any more leaking then certainly run a flush through to remove oil residue from coolant and replace.

[EvenM]

If its leaking that much oil into the coolant then flushing right now probably isn't going to achieve anything. I'd get the head gasket replaced and then replace the oil & coolant. Once you're sure there isn't any more leaking then certainly run a flush through to remove oil residue from coolant and replace.

Okey, thanks

[ChrisG]

Not sure about these cars but many Audis have a small heat exchanger between the oil filter and the block
[ warms the oil up ( when engine cold) and helps to cool down ( when coolant up to temp)]
These can eventually fail internally and mix the two liquids. Possibility - if fitted to S2s ??
I had to replace one on an 80 Sport after 20 years !
£ 45 approx from the dealers.

[irishs2]

Could the oil/water exchange be happening in the turbo?

[EvenM]

I have replaced the org turbo for a used rs2 turbo , could that mix liquids?

[macspring]

Not sure about these cars but many Audis have a small heat exchanger between the oil filter and the block
[ warms the oil up ( when engine cold) and helps to cool down ( when coolant up to temp)]
These can eventually fail internally and mix the two liquids. Possibility - if fitted to S2s ??
I had to replace one on an 80 Sport after 20 years !
£ 45 approx from the dealers.

I think this is more of a Mk 2 Golf vintage type thing, and a similar vintage 4 cylinder Audi engine.

Don't think it applies to an I5.

[SteveH]

I think this is more of a Mk 2 Golf vintage type thing, and a similar vintage 4 cylinder Audi engine.

Don't think it applies to an I5.

Oil sandwich plate. S2's don't have them

[220bhp]

Did you check the head for corrosion around the water ways. It is quite common on these heads where the wrong coolant has been used in the past.
Heads should be pressure tested and checked for straightness when taken of, and if necessary be machined.
These heads are now over 20years old. that's a lot of heat cycles.
Best of luck getting it sorted

[EvenM]

Did you check the head for corrosion around the water ways. It is quite common on these heads where the wrong coolant has been used in the past.
Heads should be pressure tested and checked for straightness when taken of, and if necessary be machined.
These heads are now over 20years old. that's a lot of heat cycles.
Best of luck getting it sorted

I'm not sure, I had someone to look at the head. Thanks for the tips, better check those things this time

[EvenM]

Update: I found two places on the turbo side where it looks like oil is coming out from the head gasket, should I try to tighten the arp studs more? I have not tighten them after test drive.