Having a lot of trouble with my 87 build i would really appreciate any advice

Austin__mk3

New Member
Aug 4, 2023
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0
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I bought an 87 automatic Supra July and it was amazing until my issues got worse. The problems started with overheating while idling in traffic but there was never a sign of bhg. I was driving the car home one day a couple weeks after I started trying to fix the overheating problem and the car seemed like it was misfiring, it wouldn’t pick up at all . I found an oil leak at my valve cover gaskets and changed them out but when I was changing the spark plugs the last one broke. When it broke, half of it fell off the treads and down my engine. After that the car was ran ( not by me) and I don’t know how damaged it is. I don’t know if the damage should be expected to be permanent or salvageable. At this point I have no idea what I should do and I just need my car back man. I have money for a rebuild kit but I don’t know if the damage is too far past a rebuild. I could always 1j swap it but I don’t think I’ll be able to do that anytime soon. The car had no other problems and was daily driven for about a month until this started happening. The 7m I have only has 150k miles so if I could save it I’d rather do that. I’m very overwhelmed with this situation and just don’t know what I should do. I just want my car fixed the fastest with the least money spent without cutting corners. Any advice would help thanks,
 

alcyon

Active Member
Jun 15, 2017
163
35
28
Kuala Lumpur
You might be overheating due to a faulty clutch fan. To remove that damaged spark plug, i think you have no choice but to remove the valve head.
 

Bru

Member
Feb 28, 2013
57
32
18
Tampa Bay Area
Make sure you have enough coolant in the system. Low coolant is indicated by the temperature needle whip lashing back and forth. You could drain out some coolant and test the thermostat by placing it in a pan of water then heating it up near boiling. The valve should open at the rated temperature or about 180° F. Make sure it's installed in the correct direction. The spring part goes into the thermostat standpipe housing with the jiggle valve at the 12 o'clock position. Be careful not to strip the (2) 10 mm bolts that cover the thermostat. A very thin smear of silicone is helpful To seal the surfaces. Another thing to look for is dirt, leaves, and cobwebs sucked up in front of the radiator blocking airflow. If you take off the 2 top straps, you can carefully tip it back to take a peek in there. You can use a low-pressure hose to backwash it being careful not to damage the cooling fins.
 

SupraTrbo89

Member
Sep 21, 2006
229
3
18
West Chester, PA
If your thermostat is stuck closed the top of your radiator will still be cold while overheating. Mine use to overheat and I would pull over and the top of the rad would be cold. I'd restart the car and the needle would suddenly drop as the thermostat opened. The top of the radiator was also red hot. Just a quick way to tell if the thermostat is stuck closed.
 

Yellow 13

Lurker
Apr 4, 2006
2,308
0
36
Fairfield, California
Overheating can be caused by alot of things. So cheap stuff first: Check for any blockages between the radiator/condenser area like bags or leaves you may have picked up. Next check that the fan clutch is engaging and the drive belts are good and not slipping. Next check that the rad cap and thermostat are both working at correct temps/pressures, plenty of youtube videos on how to test. If theres no visible signs of leaking Id pick up a pressure tester and test your coolant system under pressure, If it does lose pressure and you see nothing leaking outside then it may be a BHG internally. Id invest in a cheap amazon borescope and peek into the cylinders for coolant and check the oil for the usual milkshake. You can also use it to inspect for any damage caused by the plug dropping in. You could also use it to inspect the water pump without removing it. Ive seen cheap autozone pumps have their blades disintegrate and show no signs externally of a bad pump. Personaly Id pull the pump off and inspect it since its so easy on MKIIIs. Thats the easy stuff. You could have blockages but Id work through the usual stuff before digging too deep.