Technical Fiat Punto 75 SX Overheating

[DigsySE18]

Hi
Fiat Punto R Reg 75 SX
It has just overheated today, its not the head gasket (that's been done recently) - breakdown guy thinks it might be thermostat but on reading other posts I think better see if its just air in the system.
Water level was very low, have topped that up. Can someone give me a real idiots guide on how to bleed air out of the cooling system - preferably with photo's??
Also, how easy is it to change a thermostat - is it so easy your Mum could do it (I might have to!)
Thanks

 

[dave]

there is already a guide in the guides section

 

[DigsySE18]

Thanks - just found guide to bleeding the system ... How easy is the thermostat change?

 

[dave]

2 bolts an a hose clip

 

[DigsySE18]

Seriously? Unclip hose, unbolt thermo, put in new thermo, rebolt and connect hose again? Sorry to sound dense, this is Mum speaking and will probably have to do it meself!
Where is best place to get thermo?
Yes you are talking to the completely noddy person!
Thanks for your help!

 

[dave]

oh also make sure surface where it bolts to is clean before fitting new one, you get them from a motor factors, local ones will be listed in yellow pages. they are about £12

 

[DigsySE18]

OK thanks, have driven car today, its fine til idling in traffic then temp goes up quite quickly, does that point to thermostat? In my limited knowledge that means the fan's not cutting in?
Thanks.

 

[dave]

thermostate usually ready low when its broke, is your fan coming on?

 

[euro]

OK thanks, have driven car today, its fine til idling in traffic then temp goes up quite quickly, does that point to thermostat? In my limited knowledge that means the fan's not cutting in?
Thanks.

If its fine when you are not in traffic i would doubt its the thermostat. More likely to be the fan not cutting in. There is a fuse for the fan in the panel below and to the right of the steering wheel.. 30 Amp I believe. There is also a fan switch half way down the right hand side of the radiator when looking from the front of the car. make sure the plug to it is connected properly and all wiring looks OK. The fan swich can be bypassed to test the actual fan. Does the fan spin freely with the engine off?

 

[Phil]

A quick diagnosis you can follow; when the engines looks like its starting to overheat and the rad fan appears not to be cutting in, feel the back of the radiator (mind your fingers), if its cold, the thermostat is likely stuck and not doing its job of circulating water to the rad once the engine has warmed up. Either that or you have a massive air lock in the rad (unlikely).
I have replaced the thermostat on my car and can confirm that its an easy job.