Golf Mk2 Overheating?

[TEREX1]

My Wife's Friend Has An Old Mk2 1.1 Litre Golf.she Has Had The Head Gasket Replaced But The Head Was Not Skimmed.the Original Problem Is Still Present In That When The Car Warms Up Coolant Is Expelled From The Expansion Tank.with A Lot Of Earache From My Wife I Agreed To Have Alook At It. The Engine From Cold Runs Ok Until The Temperature Reaches 82 Degrees Celsius Then You Can Watch The Coolant Expand Until It Blows Out Of The Expansion Tank At Which Point The Electric Fan Kicks In And The Level Drops Immediately.
The Temperature Drop Across The Radiator Is Between 9-14 Degrees Celsius. The Heater In The Car Works As It Should.
Has Anybody Any Specs On This Model
Thermostat Opening Temp,fan Kick In Temp Etc
Any Info Would Be Appreciated

[mechy1barry]

thermostat normally opens around 90, check the filler cap or try a new one, could be weak and losing pressure.when level drops when warm,only top up to the mark on the tank and replace cap,this system runs on pressure.other probs may be-radiator fan sensor faulty(try wiring across terminals so it runs constant)water pump impellor worn-blocked rad/waterways-head gasket/cracked head.

[naterkane]

replacing the thermostat is always a good idea...

and it's a very easy job...
just disconnect the lower rad hose...
pull the two 10mm bolts out of the housing it attaches to.
and pull the thermostat out (careful, since coolant will come pouring out of the engine as soon as your loosen the thermostat.

replace it with at 80 degree unit being careful to put the new thermostat in the same way the old one came out, and make sure to put a new O ring in there as well...

your fan switch seems to be working properly...

where is the coolant going when it leaves the expansion tank?

can you see it leaking anywhere?

if not, it's possible that not enough coolant was added after the headgasket job.

what you should try to do, is pull the pressure cap off and start the car... when it warms up and the tank empies... keep adding till you see a good stream of coolant from the skinny hose that goes from the radiator to the overflow container AND the coolant is filled up to the "max" line on the overflow container...

if it keeps disappearing, then there must have been a bad head gasket job...

also check your oil, and make sure it's not gray or white...
if it is... then your water/coolant is making it's way (probably around the headgasket) to the oil...
and that is no good at all..

good luck

-naterkane