heating prob any ideas!!!!

[ABELL]

hi guys n gals. erm ive been having a little trouble with my discos heating, basically the head gasket went about three months ago and i had a new one fitted, but my heaters have been crap for about 6 months they only seem to get mildly warm, and when im driving along the heaters some times go off warm and start blowing cold, and the temperature gauge on the dash starts to rise sharpish, i dont think there was much air locked in the system as the guy who did the work said he,d got rid of the lock, but surely any air left in would of dissposed of itself by now. any info ideas appreciated. abe :)

[SteveGoodz]

Gotta say it sounds like an air lock to me.

When I've had this in the past I've run the engine with the cap off the header tank and the heater and blower on full. After a while I saw a large air bubble in the header and the water level in the tank dropped dramatically ~ like almost empty! I quickly poured in more coolant so that more air couldn't be sucked back into the system. This happened 3 or 4 times before the air was all expelled and the heater was fine from then onwards.

HTH  :D

[lurch_917]

he might of got the air out of the block but has he got it all ie: the heater matrix as i know on some cars you have to have your heater set on half with the blower going to get the air out of the system

[ABELL]

cheers guys yeh im getting more convinced it is going to be air locked ill get it looked at see if it is!! :lol:

[Ja1983]

remember that iff topping up a warm engine - use warm water!  

agree on air lock tho, have afeel of all the pipes, see if you can determine where abouts the hot/cold sections are, this may point you to the problem.

when the head gasket went, did oil get into the water? if so it could be worth taking out and cleaning the thermostat, as this could well be caked up in carp due to its position (high up in the hottest area!)