How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Mike S. Your Own Question
Mike S.
Mike S., Classic Car Mechanic
Category: Classic Car
Satisfied Customers: 7369
Experience:  A.S.E. certified with 25+ years experience.
20625509
Type Your Classic Car Question Here...
Mike S. is online now
A new question is answered every 9 seconds

Ford Mustang: Thanks.....I have a street rod 68 Mustang in

Customer Question

Thanks.....I have a street rod 68 Mustang in which they have put in a Ford 390. They cars runs fine in stop and go driving but overheats on the highway.
Radiator is 3 inches thick, 24 inches wide, and 20 inches deep.
The car has A/C
There is a 14 inch electric fan in front of the radiator and 2 10 inch electric fans on the inside of the radiator. All fans have air moving in the proper direction.
Any advice?
Bob
Submitted: 2 years ago.
Category: Classic Car
Expert:  Mike S. replied 2 years ago.
Were any of these fans just installed or did it just start with this overheating problem?
Is there a heavy coat of paint on the engine?
Are there any leaves blocking the grille?
Is the fan shroud missing?
Is there a reason a mechanical belt driven fan was removed and electric fans installed?
Have you tried without a thermostat?
Is the ignition timing correct? Sometimes the timing off will cause overheating.
Customer: replied 2 years ago.
New installation
No paint on engine
Grile open
No room for a mechanical fan
Thermostat is out now
Timing has been checked and is correct
Thanks
Expert:  Mike S. replied 2 years ago.
Are you running the ac when it overheats?
Customer: replied 2 years ago.
AC is off when running
Customer: replied 2 years ago.
AC is off when it is running hot
Expert:  Mike S. replied 2 years ago.
It's a strange thing because usually an engine overheats more often when it's not moving. When it's moving the air blowing through the grille and around the engine helps to cool down the engine. That is what is making me think that there isn't enough air flow.
Air flow from the outside air that is, not what the fans create.
So you said there wasn't enough room for a mechanical fan. How much space is there excatly around that engine for air to flow?
Try running it around without the hood on and even remove the grille for now and let me know if it still overheats when driving with the ac off of course.