probable causes

bad driver · Post by **bad driver** » 12 Apr 2004, 15:50

Hi, I recently blew a head gasket, it happened within 1 mile of having the engine in the car and on the road. I suspect somnething wrong with fitting has caused this. I need to know the most likely causes for this so I can resolve before blowing another after several hours spent fitting.
Thanks.

JohnD · Post by **JohnD** » 12 Apr 2004, 23:23

Maybe an airlock after filling the cooling system.

bad driver · Post by **bad driver** » 13 Apr 2004, 01:09

Yeah I suspected an airlock could be the cause but others have told me it wouldnt be enough on a derv due to high operating temps anyway. Someone has suggested pump timing as I had taken the pump off and put it back on. However the pump was not rotated at all, the crank wheel was locked in place and the pump was put back exactly where it came from as I drfew round it on the mounting plate!!
Also I had put the coolant back in under pressure and bled it right through the system so if there was an air pocket anywhere I am certain it would of been very small.
Is there anything else that could be a factor?

JohnD · Post by **JohnD** » 13 Apr 2004, 12:24

Had the head been off prior to refitting the engine?

bad driver · Post by **bad driver** » 13 Apr 2004, 14:49

No, the only thing that was disturbed prior to the engine going in was the fuel pump as mentioned above. I am hoping I was just unlucky and it is coincidence it blew so soon afetr fitting. I had ran the engine for a while whilst the car was on stands in the yard, 3 times I had taken it up to normal operating temperature and let the fans kick in. I had also taken it up through all the gears as it has had new selector bars put on and wanted to check everything was right with it.
It just seems odd it happened the first time it was actually under load!!