Boiling up

[davidimurray]

If I was you I would start by removing the stat. This should make the engine warm up a lot slower (the only reason for the stat is accelerated warm up). While you are warming the car up take it easy and don't give it lots of revs for long periods.

Is your header tank at the highest point of the system? If so I would start the car with the header tank cap removed. As the engine is running, work your way all the hoses on the engine, giving each one a good hard squeeze in turn and checking for any bubbles in the expansion tank and keeping it topped up. You should be able to see some water movement in the tank depending on how you have configured it. You should be able to leave the car idling without it boiling over without the cap on.

Putting the cap on - if it is a 14psi one the the boiling temp of the water will be raised to 119C.

I wouldn't run the car without the stat on the road - as the last thing you want to do is overcool it during the early stages of warming up. If you do decide to remove the stat, put a metal disc with a hole in place of the stat as this will provide with you some flow resistance in the system.