Ok this is on my Primastar (trafic, vivaro equivelant) Pulled over the other day and noticed my fans had cut in, but temp guage was reading normal. then checked header tank and when i took the cap off it boiled over.

Weird thing is temp guage always reads normal and all hoses get hot but van would seem is definately getting too hot. Thought was water pump was not circulating properly, any help is appreciated. Had enought of this van.

 

it will boil over if u remove the cap as you have exposed the system to atmosphere pressure,does it boil over when the cap is left alone?does the temp gauge to in to the red ?do you fans cut out if left?and finally is the van equipt with air con?

 

I was hoping you'd see the post been a huge help in the past. No dosent boil over if left, It doesnt have air-con and temp guage always stays in middle, has once or twice spiked though like gone high then imediately leveled out like there was a blockage or sumats.

 

what do the coolant fans do?do they cut out?do the go in stages with regards to speed?i.e go faster all of the sudden?

 

Oh yeah the only thing that makes me think its overheating is that the fans come on even when I havent been sat in trafic. They just come on after ive been driving for a while then cut out say 30 seconds after i turn the engine off.

 

Sounds about normal to me mate tbh!this is a 1.9?

 

Yeah mate its a 1.9. Just worried as my mate had one and it was overheating but he didnt realise and it cooked the engine. Why wouldnt the temp guage how it?

 

temp gauge should of shown it!do ya heaters get hot?have you checked the hoses and rad to make sure the circulation is good?you could always run it up get the fans in wait till they cut out then slowly undo the cap,it should not boil over at that stage!i presume you have no nasty noises from the cambelt area?i see you are doing ya belt!always good practise to check ya pump for play and to check the bearing by simply spinning t and see how it feels!(much the same way u would check the wheel bearing!)

 

Sounds to me like it is doing what it should.
All cooling systems get hotter when the engine is turned off, as water stops circulating so it gets hotter, enough to put the fan on, which cools it down enough for them to go off.
tabetha