'89 Mustang Overheating - Help

Question

1989 Mustang LX convert. (90K miles) is overheating. Installed a new radiator, new pump, new fan, new radiator cap. I have removed the thermostat and the problem still continues. There is no white/sweet smoke coming from the exhaust. What else could it be.

Answer 1

How do you know it is overheating?   Is a light coming on?  Do you see steam coming from the engine?  Need more details.

Could be anything from a faulty light coming on to something else.  

Answer 2

put the thermostat back in  with out it water can flow to fast thru the rad an not cool down also you might have the car checked for a cracked head or bad heaf gasket. Any good rad shop should be able to help or any shop with a 4 gas analizer

Make sure the belt is on right a belt put on wrong can cause the water pump to run backwards.

Answer 3

Are the fans coming on, sometimes the sending unit fails and the fans won't come on. If it is a belt driven fan make sure the clutch is functioning. Also look for a high pressure coolant leak, if the car overheats while driving you may be losing coolant somewhere when under pressure and the coolant loss is causing the heat problem.

Leave the thermostat out until you figure it out, a pegged gauge means a severe issue like no fan or major restriction in a coolant passage.

The "it could run hotter with no thermostat" theory is a wives tale, the theory that the water won't stay in the radiator long enough to be cooled would also mean the water won't stay in the engine long enough to be heated. claiming one will happen & not the other violates the laws of physics. I have never seen this happen.

Good Luck!

Answer 4

If it is running bad, there may be damage to a cylinder head or gasket.