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  • 1965 - 1973 Classic Mustangs -General/Talk-

Do 65 Mustangs always run hot?

  • Thread starter Thread starter kefta4ever
  • Start date Start date Jul 30, 2018
K

kefta4ever

New Member
Jul 29, 2018
11
0
1
La Mesa, CA
Jul 30, 2018
#1
  • Jul 30, 2018
  • #1
Hi, we changed the radiator on my sons 65 Mustang, Its aluminum. My son says the car always run above the middle and high when idling for a while. I know the cooling system is working and we just replaced all the fluid. I looked for a larger radiator but did not find one that fits. Besides I already put the new one in. Is that just the way they run or is something wrong?

65 Mustang, 289.
 
G

GOvert

15 Year Member
Jan 27, 2007
491
100
63
north central Tennessee Valley
Jul 30, 2018
#2
  • Jul 30, 2018
  • #2
Yes they do. Make sure your thermostat inside the gooseneck is a 189 or 190. 160 opens too frequently and causes heat build in the radiator. also install some kind of recovery jug if you don't have one. Two months ago I added a 16" electric fan to the front side (the side I can see in your picture) with a fan and Haynes fan controller. The customer is always in parades driving slow or stuck in stalled traffic in his overgrown town. He wasn't getting the additional air flow that you get at normal cruising speed. He said it helped a lot at slow speeds. I hope this helps !
 
K

kefta4ever

New Member
Jul 29, 2018
11
0
1
La Mesa, CA
Jul 30, 2018
#3
  • Jul 30, 2018
  • #3
Thank you very much for the reply. You wouldn't happen to have a link to the fan you are speaking about? The recovery jug is installed, I'll check the book of invoices to see if it gives the thermostat #. As you stated the real problem is city driving in traffic. My son bought it as an everyday driver, and although he takes good care of it, I'm sure problems will arise, and he is quickly becoming a mechanic.
 
G

GOvert

15 Year Member
Jan 27, 2007
491
100
63
north central Tennessee Valley
Jul 31, 2018
#4
  • Jul 31, 2018
  • #4
Here is one with a controller. I havn't ever used this particular type of controller but I noticed the sensor would thread into the pipe thread hole on your gooseneck where a pipe plug currently exists. It will just fit between the radiator and hood latch support. You have to take out the radiator, place the fan in the space for it. Replace the radiator, then attach to it. Wire it to push (blow) through the radiator towards the engine. Leave the stock belt driven fan in place. It's worth a shot. link below:
Fan & controller
Take pictures of your install and post a new thread on STANGNET !
Other search results
 
Last edited: Jul 31, 2018

horse sence

15 Year Member
Nov 29, 1999
12,314
8,172
233
Wile Coyote's stunt double
Aug 2, 2018
#5
  • Aug 2, 2018
  • #5
I kind of think the new gaskets must have somthing to do with this . My old 66 fast back never over heated ,i ran a 160 thermostat . If i ran a 180 it would get a bit warm . I went through a car show with it idleing for a good 20 minutes ,i could see hoods poping up behind me but mine always stayed around 180 . I used the print seal gaskets from felpro ,i think the new gaskets are designed for the newer 5.0 and water doesnt flow through the block like the older motors would
 
G

GOvert

15 Year Member
Jan 27, 2007
491
100
63
north central Tennessee Valley
Aug 3, 2018
#6
  • Aug 3, 2018
  • #6
From Stangnet's Archives
 
R

rgsauger

Member
Aug 8, 2018
48
10
18
Houston
Aug 21, 2018
#7
  • Aug 21, 2018
  • #7
Talking about head gaskets, you have to make sure that the steam holes in the block align with the holes in the gasket and the holes in the head, especially if you are running aftermarket heads for a newer 302. If you're aftermarket heads do not have the holes, you must drill them.

Next, I cannot tell from the pictures if you are running a good fan shroud or not. The shroud is critical especially with a mechanical fan.

Lastly, do a search for Taurus fans. Very common upgrade that I am doing right now on a 65 Mustang with a very healthy 289 is to upgrade to the Ford Taurus electric fan assembly. You can also use the Ford contour fan assembly. Just do some reading. You will most likely have to upgrade your alternator to 100 amp plus if you have not already.
 
B

Baja Traveler

New Member
Jun 9, 2016
5
0
1
Aug 22, 2018
#8
  • Aug 22, 2018
  • #8
Mine did for sure - but once I put a fan shroud in it runs fine with the improved airflow through the radiator - instead of around it...
 

The Shemdogg

Active Member
Mar 15, 2016
137
23
38
san jose CA
Aug 22, 2018
#9
  • Aug 22, 2018
  • #9
Maybe your clutch fan is bad? I have no shroud on mine but a new fan clutch and mine stays cool

shem
 
S

Speedman

New Member
Jul 24, 2018
4
0
1
Jacksonville, FL
Aug 28, 2018
#10
  • Aug 28, 2018
  • #10
I have used a product called Water Wetter for years. Buy at any auto parts store and follow the directions.
 
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