Newbie with a question!

[anarchy187]

So I am a proud new owner of a 1988 Turbo supra hardtop all black, It has 150,000 miles on the chasis and 20,000 on engine(Had a full rebuild with performance parts) It has eagle rods, forged pistons, arp studs, hksmetal headgasket, has stock ct26 at 7psi, injectors, and ECU.
The car is over heating and I was wondering if it made 20,000 miles is it possible that if it has a metal head gasket and it already made 20,000 miles could a possible retorque solve the problem? Or possibly a temporary fix? I have alot of experience with cars and engine building and know that this is a long shot, but I have never had a MHG fail on me(I always do the proper prep though and retorque)
I just wondered if this could possibly stop the leaking, and if anyone else has done this before with good results.

Thank you everyone and look foward to let you know the results of what happens.

[Krem]

not sure what you torque'd the head studs to when doing the rebuild (believe it's recommended to use studs w/ a MHG). However, I know the factory settings are false and very under torque'd, leaving the HG's to blow.. surely there's someone that has the exact torque spex, I believe they're somewhere around 72 or 74 lbs/ft torque if I remember correctly. Sorry couldn't be of much more help, but I am still learning my supra and can only note what I know.

[Bill UK]

Over heating doesn’t necessary mean BHG, other things could contribute to over heating, thermostat, water pump, radiator condition, to name a few. The first thing I would do is a block test Link . If the gasket has failed then a re-torque after 20K would only be a temporary fix, if it did worked at all. I replaced a head gasket on my first Supra many years ago, drove about 15 miles down the road only to find it over heating again. The bock test shown negative, so I decided to pull out the water pump, only to find the impellor had disintegrated leaving only one impellor blade. The problem with an over heating Supra is that we get paranoid about head gasket failure, fortunately in some cases it’s not always the issue.

[86.5supra]

I had the same problem after my motor was rebuilt. My engine builder took the motor back out and tore it down. Found nothing wrong put a second HG in it just to have the same problem within twenty miles. He then brought in a guy who is known for some very fast imports. He said due to the extra HP the motor produced more heat than the radiator could handle. We did a larger radiator and dual electric fans. I have not had a problem since temp does not go over 180.

[anarchy187]

Thx, everyone! Just out of curiousity when the head gasket fails how long does it usally take for the engine to overheat? I figured it would go in this order for overheating
1.Thermostat for very fast over heating
2. BHG for longer than 5 minutes
3. Waterpump for longer than 15 or so.

[Bill UK]

Depends on how long the HG has been failing and how efficient the water pump is. In my case with the water pump impellors disintegrated , I would swap 2 and 3 around. with BHG at the bottom of your list.

[MA70-3.0GT]

A BHG (assuming it is causing overheating) could take any amount of time depending on how quickly air is escaping and causing the airlock (or how much coolant is escaping/how long to deplete system enough to overheat whats left).

Do you actually have any other symptoms of BHG? If it's a BHG causing the overheating you have to be losing coolant at the very least, either blowing out of the overflow tank or burning it. To be honest it could just be something simple if the head was torqued & everything prepped properly. How long is it actually taking to overheat (is it actually overheating, what is the engine temp measured independently of the gauge?).