Oil in the cooling system

[liam_w]

Hello all, I have a 1991 vw t25 1.6 td, it has done roughly 90.000 miles. On a trip to the lakes around 4 months ago it constantly overheated when on the motorway, usually on an uphill section. After we got back the engine started tappeting a minor amount when under load and kicking out a lot of smoke from cold right through to when warm. There was only water in the cooling system as we were going to put coolant in when the cooling system work was done, then after the recent cold weather, we discovered oil in the water system and it's kicking out a lot more smoke, as well as making a minor knocking noise. Throughout the temperature gage has always read very cold even on a long run until it suddenly overheats. Does anyone know what is wrong??? Has the Head cracked?? engine dead??? or something simple?? If so does anyone have any idea about cost's and good places to get it done??? Thanks, Liam

[Simon Baxter]

Service it properly.
replace the oil/water heat exchanger thingy between the filter housing and the oil filter itself.

[mrted]

Hello (imho) it sounds like a head/head gasket problem, it might be that the head was refitted with a new gasket when it was a little warped,
have you had the van a while and has anyone changed the gasket recently ? you can usually tell by looking.
Oil in the water is either the head gasket leaking, a badly cracked head or (as previously said) the heat exchanger under the filter corroding.
Smoke could be oil finding itself past the head gasket into the combustion chambers (if its using oil) if the head gasket is compromised.
Did the coolant freeze when you had the cold weather, as that would make the head gasket problem worse as water expands when frozen and could force the gasket apart.
The knocking/tappety noise I'm not sure about
I had nearly the same problem on a mk 1 golf diesel

Good luck

John