I went for a drive this morning and then parked the car up, I came back to it five minutes later to go out to work but the temperature gauge was reading very high, almost in the red. On starting the engine, within 20 seconds the temperature had come back down to 3 bars. Is this likely to be the result of an airlock? Possible headgasket failure? Dying water pump?

I changed the radiator a few months ago but didn't have this problem until today, I'll be pulling the engine in a few weeks anyway to do some work on it so am not really too worries but it would be nice to diagnose it beforehand.

 

you probably didn't bleed it correctly after you changed the rad, nowt to do with your water pump

 

Bleed the rad, i had this after having my inlet manifold off

 

It might just be a case of the coolant not circulating in the system for a short while and heating up.I had a mk1 escort that use to do that.

Provided the temps are normal when its running it should be ok.

 

I had that after my recent dyno session, the car had been sat for a while after its mapping, heated the water up in the block and then started the car and the temperature went through the roof. 2 mins later and since, everything has been fine.