overheating HELP!!!!!!!!!!

Phoenix · Post by **Phoenix** » Sun Mar 07, 2004 5:48 pm

its over heating and the fan doesn't kick in, its a 1272cc MkII breadvan

right its not the :-

Thermostat
the plug on the side of the radiator as its new (did it today)
or the fan as we know that works

there are two plugs just under the dizzy cap that we don't have a clue what they do, any info would be much appreciated

optima21 · Post by **optima21** » Sun Mar 07, 2004 6:46 pm

if the fans not kicking in its got nothing to do with the engine.

its simple to check electrically.

1) make sure you get a 12v supply to one of the wires in the connector to the fan switch at the side of the radiator. if theres no voltage their its possibly the fuse, so check that.
2) if theres a supply voltage there short the contacts on the connector out and if the fan works its the switch thats probably knackered. if the fan doesnt work its probbaly the fan that knackered.

amstrange1 · Post by **amstrange1** » Mon Mar 08, 2004 9:25 am

It could also be an airlock in the radiator. When we dropped the G40 into my car we were very careful filling with coolant, but must have managed to get air trapped in there somehow. Checked all the connections, shorted out the fan switch to get the fan to cut in, reconnected it all and started swearing. Then there was a loud gurgling sound and a few seconds later the fan cut in of its own accord.

optima21 · Post by **optima21** » Mon Mar 08, 2004 1:28 pm

True it could be Andy, and theres a white knob on the heater control valve (on the heater) that is a bleeder. if you undo it while the engine is running there should be a little trickle of water.

amstrange1 · Post by **amstrange1** » Mon Mar 08, 2004 3:30 pm

Yeah, trouble is the bleeder isn't foolproof - I'd even flushed the coolant system through several times before filling it and still got the bloody airlock. Everything had been done by the book - yet when I'd changed the coolant on the old engine I'd not taken as much care and it'd all been fine. Just one of those things I guess - it had me and Paul B worried for a while though!

Phoenix · Post by **Phoenix** » Mon Mar 08, 2004 4:03 pm

right done all that and narrowed it down to the 2 sensors under the dizzy but don't have a clue what they are or what they do, one is blue and one is black, i have 2 new ones from the scrap yard which i have cleaned up and i'm hoping they work, (five finger discount so i mayaswell as try) so any info on these might be some help cheers