h.e.l.p.....overheating
 

my son just purchased a 1991 supra turbo with a blown head gasket. He did some research and was told the best guy around to go to worked at the toyota dealership. So far he has replaced the head gasket, the radiator, fan clutch, the hoses, radiator cap etc etc etc.. The car sounds great, everyone who looks at it says it runs wonderfully. The minute he drives it under a load (up a hill) it overheats. There is no coolant in the oil, and no oil in the coolant everything looks clean. He had other work done also (new brakes all the way around, new tires etc etc.) he is into this guy for about 5,000$ and a this point the mechanic has no idea why it is over heating still.. Help !!!! he puchased this car in November of last year and has not been able to drive it yet. He is getting very discouraged. Loves Toyotas, is there something this guy could be overlooking, the shroud also looks great. He did remove an undershroud that we thought might direct air from under the car up to the radiator as there is a whole bunch of stuff in front of the radiator ( all stock) which might block airflow, he dealer says this is just a road shroud and would not effect the cooling situation

water pump? obstuctions in the block? new radiator cap?
Might be a chance the motor was rebuilt before and bored out, that would make the walls thinner and it would be harder to cool.
Maybe an oversize radiator would be a good idea. I live in kuwait where the temps are hot and I had a custom 3 row radiator made and my car runs cool all day where before it would get hot in the summer with the stocker 2 row.
How is the airflow through the front grill while driving?
The under cover is a good idea to keep on the car. I hit a puddle one time without it and my motor quit cause water went everywhere in the engine compartment. I had to pick it up after work and it started right up.

whats it do at idle? what about with the ac on? temp guage move up or down? both 7mgte's i bought with "head gasket repairs" still had the same heating issues, so i replaced the head gaskets and hadnt had any problems yet :) what about the overflow bottle pushing out coolant?

Is it blowing white smoke? This might be a dumb question but does it have the proper amount of coolant in it.

we dropped it off again last night, it ran fine all the way over there. When he started it up it pumped out about 1/4 of water then the exhaust was dry, no white smoke. The guy torqued the heads beyond factory specs. We checked coolant ratio, it was approx 50/50. It seems to be an intermittant problem but neither my son and I are mechanics and this guy doesn't take questions well. The proverbial "I have forgotten more than most people think they know" He came highly recommended but now we are in a tough spot. The car does not cool consistantly, we don't know of anyone else around who will touch it, never mind the 4k+ hes got into it. When it runs cool it runs extremely well but he is afraid to drive it because if it is not the HG right now he does not want to blow it again. Right now the guy is talking about re-torqueing and maybe pulling the head off it and having it checked again. I just hope he is using his wallet this time, my sons is running dry on a car he can't drive........is this the love/hate relationship I hear about on the supra????

does it bubble over and spit water or is the temp gauge just saying it's overheating ?

do you spit water onto the intercooler from the over flow tank upfront by the drivers headlight ?
do you see water ?

yes ....and yes. When it overheats it spews everything out

just as a concern when retorqueing use arp bolts not the factory ones the stress may cause them to snap in half and then you will have a bhg

also have you ever burped the system? that might help just going from what happened to my girlfriend's na

look at my block and you can see why just replacing the headgasket might not be good enough
http://www.ddmcse.com/turbo/images/process/0hrs.JPG

not being a mechanic, I assume it is because it is an uneven surface correct? But if the guy took the head off to replace the gasket, wouldn't he have seen that the surface looked like this and therefore would have had it ground or whatever they call it...to give it an even surface............did this guy just cut corners and charge him big $$$$ and not do the job properly????