Please help once again....

About 3 to 4 weeks ago, I posted my 740T overheated, blew trhe radiator and started running on what seemed to be two cylinders. What I have done since is replace the radiator with a new one, all the hoses, thermastat, plugs, wires, cap, rotor, coolant tank, cap, and air cleaner. The car runs fantastic!!! The pick up is awesome and the car is a lot quicker than it was.....But it still overheats, like a siv. I've checked the timing and the belt and it's fine, The converter is clear, I'm at a loss. I loose coolant but not by dripping, and no white smoke through the exhaust, not in the oil...... What do I check next? Signs of a cracked head??

Rick Plett

Sounds like a leaking head gasket. You should start by pressure testing it and seeing if the coolant is leaking externally somewhere. If not then pull the spark plugs out and see if it is getting into the cylinders. You obvioulsy cannot see a great deal into the combustion chamber area through the plug holes, especially on a turbo, but sometimes you get lucky and can see signs of the coolant on the piston face. If none of this tells you where it is going I suggest you have a block check performed on it. It will detect the presence of exhaust gas in the coolant which is your indicator of a leaking head gasket or cracked head. Although I am sure that you could crack one of those heads I have never seen one cracked in all the years I have been working on them. I have seen them bent/warped to hell from being overheated though.

Rule 308,

Thanks, the car did do a massive overheat a couple of weeks back, I drove about 3 miles with it overheating, (I was too P'd off), I figured it might be the head. I just put $600 into the work I did, how much more do you think an upper half rebuild would cost with a new head?

See steelseal.com

Or fix it the proper way and avoid the potential damage that something like steelseal could create.

A head gasket on a turbo isn't that difficult. Maybe $400-$500 if your machine shop is on the expensive side and you stop by the Volvo dealer for new fasteners. You could easily cut that price in half and still have a very liveable result.

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alex

'89 765T, 173,9xx mi