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88' GT Running Hot

  • Thread starter Thread starter VAFOX
  • Start date Start date Jul 28, 2011
V

VAFOX

Member
Apr 13, 2011
72
0
7
Jul 28, 2011
#1
  • Jul 28, 2011
  • #1
I purchased the car about 10 months ago. Haven't driven it much since I've continued to run into issue after issue. It is a rebuilt motor changed over to carb. One day while replacing a bulb in the speedo, I realized the temp gauge was not hooked up. The needle was positioned as if it were running normal temps.

I bought an aftermarket gauge and quickly found that it was running hot. It hit about 220-225 and then I parked it again. I put a 180 thermostat in it and that didn't work. Put a new water pump on it and that didn't work. Put a new radiator on it and that didn't work. Now I am at a loss.

I actually had a shop do the radiator and asked them to make sure it wasn't running hot prior to re-installing all new a/c parts and charging the system. Lots of money later, they said it never broke 180 while in the shop. However, it broke 250 on my aftermarket gauge on the way home from the shop. They've been no help since.

I've since checked the coolant, which was low, borrowed a different gauge, which also started to run hot (205) after about five minutes at idle. I turned the car off at this point because I noticed steam or smoke coming from the breather filter that is in the neck of the oil spout coming out of the valve cover.

I am not sure what to do from here and was hoping someone could help. I am fresh out of cash and cannot drive the car. Does the stuff coming out of the breather filter signify coolant steam and a head gasket problem? With the old radiator, I started it with the cap open and coolant eventually started to come up to overflow out of the where the cap is. Now I have the new radiator. Could the new thermostat be bad? I put it in with the spring side to the block, which I think is correct.

I've got a holley 670 carb, air gap intake, gt-40p heads and ford racing headers. I read something about differences with timing on the gt-40p heads. I had a shop tune the car with a 6AL box and vacuum secondary msd distributor.

Please Help!!!
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Jul 29, 2011
#2
  • Jul 29, 2011
  • #2
At 250 degrees you may have warped the head by now, thats very hot.

What fan set-up is on the car? Do you have the black plastic air deflector under the radiator support installed still?
 
V

VAFOX

Member
Apr 13, 2011
72
0
7
Jul 29, 2011
#3
  • Jul 29, 2011
  • #3
It has the stock fan setup and has the fan shroud. Not sure about the air deflector.

What do you recommend I do? Pull the heads and have them checked? I am out of $$$ since the shop went ahead and did the a/c work. I was thinking of getting another thermostat to be sure I didn't get a bad one.

Oh, and it was probably running about 275. The gauge stops at 250 and the needle went past that point. I didn't think to look at the temps since the shop said it stayed at 180. I just happened to look down and
 
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