280i overheating.

[sjp76]

Ok, I've had loads of problems with my cooling system lately. I've reaplaced all the hoses, the viscous fan, the water pump and thermostat and taken the rad out and flushed it (no blocks or anything). After doing all this, the pressure was still building up way too high and the pressure cap was blowing. I've just had the heads stripped down and gaskets replaced. but still the problem persists. I'm wondering whether there may be a crack in the block which is leaking pressure into the water jacket, and I'm thinking of a recon engine. I obviously don't want to spend all that money, before I've exhausted every other possibility. Is there anything I've missed. If i'm gonna have to replace the engine, I wanna make damn sure its going to solve the problem. Help please!!!!

[sjp76]

Guys,

I've had the engine pressure tested. with the engine still hot and the system depressurised comnpletely at the start, system gained about 8lbs in a few minutes. That sounds sounds like a lot to me, considering any pressure caused by water expansion would've already occured and been released, but I'm no expert.

The engine does run on unleaded, but used to run fine even after the head conversion, so can't see that the head has been damaged when this was done.

Ian, can you explain the timing theory please.

Cheers,
Steve.

[sjp76]

The advanced timing may well cause it to overheat, but I didn't think it would account for the large and rapid build up in pressure in the system. Wouldn't that have to come from the engine somewhere?? Its really weird cos theres no water mixing with the oil, so possibly there's a crack between one of the cylinder walls and the water jacket??

[sjp76]

Cheers Ian,

Found what looks to be a good company that specialises in Ford engines (specialisedengines.co.uk). They invite you to come down and see the build process which I like the sound of cos it means they've got nothing to hide. I'm looking at around 1500 quid including fitting. Not the cheapest quote but worth it for piece of mind. Everything is crack tested and, if i prefer and don't mind waiting a week, they'll recondition my lump rather than replacing it with another one. That way (assuming the block isn't knackered) i get to keep the same engine number. Sounds good to me, Just hope it sorts everything out. What do you think?

Steve.