Cooling problem

[itavaltalainen]

to fit the thermostat on a 2.0 8v the wrong way round you'd need a hammer..... cos the flange won't go back on otherwise.

heater does not need to be on max. the matrix is ALWAYS in the loop. fill expansion tank with 1l water, then 1l coolant concentrate, then place cap back ON! start engine, kneed the bottom and top rad hose, rev engine from time to time a bit in short bursts (just pull the throttle cable on throttle body). when the coolant falls well below min turn engine off - open expnasion cover with care (if scared let it cool down a bit).... top up again.... replace cap... start engine kneed.... reapeat this it no longer goes below min...
now take it for a 5 mile spin.... when you come back allow to cool down and top it up again.

that should be it.... never had any issues when i did this.... (the reason you want the cap always on is to avoid the water boiling in the head => releasing gas)

[madsb]

to fit the thermostat on a 2.0 8v the wrong way round you'd need a hammer..... cos the flange won't go back on otherwise.

heater does not need to be on max. the matrix is ALWAYS in the loop. fill expansion tank with 1l water, then 1l coolant concentrate, then place cap back ON! start engine, kneed the bottom and top rad hose, rev engine from time to time a bit in short bursts (just pull the throttle cable on throttle body). when the coolant falls well below min turn engine off - open expnasion cover with care (if scared let it cool down a bit).... top up again.... replace cap... start engine kneed.... reapeat this it no longer goes below min...
now take it for a 5 mile spin.... when you come back allow to cool down and top it up again.

that should be it.... never had any issues when i did this.... (the reason you want the cap always on is to avoid the water boiling in the head => releasing gas)

Thanks, great to have a step by step will take out the tstat and put it in a pan to see if it's actually working. Then I'll do this.

[madsb]

Tried steps above (haven't tested tstat yet) and the bottom rad hose never got warm.... So I guess that the tstat is dead.. I'll take it out to verify.

[madsb]

ALSO: There's no warm air coming out of the vents even when the coolant temp displays 90 degrees.... Is this also due to the tstat or what?

[sharki786]

Bottom hose only gets warm 1ce the temp needle is very close to half way. After that it gets very hot to touch.

[sharki786]

You got air lock mate. Sometimes its a cnut to get it out depends where the air is

[GOLF-MK3-GTI]

No hot air = worn out water pump.

Had same issue with a mates Saab. Car stopped giving out hot air, changed thermostat, still no air, took it out and tried it, still no hot air. Changed water pump. And we got hot air.

[madsb]

No hot air = worn out water pump.

Had same issue with a mates Saab. Car stopped giving out hot air, changed thermostat, still no air, took it out and tried it, still no hot air. Changed water pump. And we got hot air.

Okay this is getting quite annoying.. Just tested thermostat, it works fine.. I really don't need a broken water pump atm....

How can I check if the water pump is broken? And how do I check to see it's not just air ? And how do I remove the air?? why didn't vw install a bleed valve.....

edit: also, there was hot air before taking it all apart

[itavaltalainen]

have a look if you can see water coming out the thin hose that comes from flange and goes to expansion tank.

at slightly over idle you should see a fairly continuous stream of water coming out... if not check if its blocked.... if its not blocked your pump rotor and shaft are no longer joint together (happens with plastic rotors sometimes)

[madsb]

They are still connected.. I have the pump out, and can see the rotor turn

This must leave air in the system as the only problem.... I tried massaging the upper and lower rad hoses with the engine running but to no avail.. there still wouldn't flow hot water into bottom rad hose.