Loosing water and overheating!!!

[lewskisdub]

I have an 87 plate 2.1 injection T25....I need help!! So I changed the header water tank, then my overheating/loosing water problem went away for a couple of day. Then it came back. Checked the thermostat,all good. Checked the water pump,all good. Changed the radiator '2 speed' thermoswitch which is at the base of the radiator. The next couple days were happy motoring then alas...back to over heating/red water light coming on!! When I check the header tank its very hot but all the water has gone into the expansion tank. Im totally lost with what to do next. No obvious leaks in the water system. Is it worth changing the expansion tank?

[kevtherev]

I think it's time for a combustion gas test to see if your getting combustion gas pressure from a failed head seal.

[Mocki]

did you change the cap on the header tank at the same time?
where did the header tank come from? GSF?
could be a faulty header tank.....
and or cap.

[Ian Hulley]

did you change the cap on the header tank at the same time?
where did the header tank come from? GSF?
could be a faulty header tank.....
and or cap.

Agreed with all of this

[lewskisdub]

I got the header tank from Brickwerks but didnt get a new cap. Hopefully its this which is the problem. Ive had a 'VW SPECIALIST' look at this and another mechanic and both of them couldnt get to the root of the problem. Been on the verge of wanting to sell the van because of this. What exactly is a gas chamber pressure test? Does anyone know of a good mechanic in the south wales area?! Thanks for your help people.

[kevtherev]

I got the header tank from Brickwerks but didnt get a new cap. Hopefully its this which is the problem. Ive had a 'VW SPECIALIST' look at this and another mechanic and both of them couldnt get to the root of the problem. Been on the verge of wanting to sell the van because of this. What exactly is a gas chamber pressure test? Does anyone know of a good mechanic in the south wales area?! Thanks for your help people.

Most good garages will sniff the coolant for combustion gasses. Its not a pressure check.

Cant help with the garage though
Sorry

[ghost123uk]

Most good garages will sniff the coolant for combustion gasses.

Yep you need to get this done, as Kev says and the others said.
If the garage you go to does not have the correct gear for testing the water bottles for combustion gasses then WALK AWAY and find one that has.

If the result is there ARE combustion gasses present, tell us on here before making any commitments with the garage !

btw, don't drive it whilst it is overheating as this can do costly damage to these engines.