Coolant issue

[Neil B]

My son has a 1998 Caterham Roadsport A with Rover 1600 K series engine. On checking the coolant level today we found the expansion tank empty. A litre of water topped it up to the correct level. We started the engine with the expansion tank cap off. When it reached operating temp water overflowed out of the expansion tank. As soon as the engine was switched off, all the water in the expansion tank disapeared. There appears to be no leaks on pipes etc.

I have been told this could be either an air lock or head gasket, although there is no mayonaze in oil cap or oil in coolant.

Any ideas?

 

[Burnerman]

I'm sorry to say there has been lots of problems with the Rover K series engine...it was fine as a 1.1 but oversizing it has caused lots of problems - blown head gaskets being the norm. I would suspect that this is the problem here.
John

 

[jonnyfishing]

Try refilling, ensuring you bleed it as per manual. Then if it happens again, as John says, look to the head gasket.

 

[jetex]

If the water mixes with the oil, then you will get the mayonnaise. The problem with these engines, is the head gasket blows between a water jacket and a cylinder. Therefore, the water will come out of the exhaust as steam (or white smoke as some people call it). It's not a good idea to run the engine without the pressure cap fitted, as you will cause problems for yourself, and will not get a true reflection of what the cooling system is doing. Run it up to temperature with the cap fitted, and check that all the coolant pipes are at the same temperature, and they are not rock hard due to excessive pressure. As has already been said, I think you're looking at head gasket failure unfortunately.