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Car Running Hot

  • Thread starter Thread starter plantmeister
  • Start date Start date Apr 10, 2017
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    foxbody overheating
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Apr 19, 2017
#41
  • Apr 19, 2017
  • #41
What are you using to measure temp?
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 19, 2017
#42
  • Apr 19, 2017
  • #42
Mustang5L5 said:
What are you using to measure temp?
Click to expand...

I'm just watching the dash gauge for the temperature
 

prgt347

Active Member
Jan 16, 2009
52
7
29
Apr 19, 2017
#43
  • Apr 19, 2017
  • #43
Are you running underdrive pulleys? Is it possible that your gauge is reading incorrectly?

Slightly different issue, but mine ran hot for years. I do have underdrive pulleys although I would probably swap them out for stock if my stock pulleys weren't rusted and useless. At idle the temp would continue to rise and if the AC was on, it would rise even faster. As I drove the temp would slowly decrease to normal, then heat back up immediately when I came to a stop (engine running). I tried a lower temp thermostat, high-flow water pump, installed a large two-row Summit aluminum radiator, new blue hoses, and tried different water/coolant mixtures, all to no avail. I ended up removing the stock fan/shroud and installed the Flex-A-Lite Black Magic fan with controller. Not cheap, but the car has never had issues since. I live in south Mississippi and can let the car idle with the AC on full blast in August and it never gets above where I set the temperature controller at. Driving, idling, full throttle, etc., no issues whatsoever.

I don't know if this will help in your situation but wanted to pass this along in case it does. It has made a huge difference for me.
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 20, 2017
#44
  • Apr 20, 2017
  • #44
prgt347 said:
Are you running underdrive pulleys? Is it possible that your gauge is reading incorrectly?

Slightly different issue, but mine ran hot for years. I do have underdrive pulleys although I would probably swap them out for stock if my stock pulleys weren't rusted and useless. At idle the temp would continue to rise and if the AC was on, it would rise even faster. As I drove the temp would slowly decrease to normal, then heat back up immediately when I came to a stop (engine running). I tried a lower temp thermostat, high-flow water pump, installed a large two-row Summit aluminum radiator, new blue hoses, and tried different water/coolant mixtures, all to no avail. I ended up removing the stock fan/shroud and installed the Flex-A-Lite Black Magic fan with controller. Not cheap, but the car has never had issues since. I live in south Mississippi and can let the car idle with the AC on full blast in August and it never gets above where I set the temperature controller at. Driving, idling, full throttle, etc., no issues whatsoever.

I don't know if this will help in your situation but wanted to pass this along in case it does. It has made a huge difference for me.
Click to expand...

Nah, my pulleys are stock.

I guess the fan was your issue. I'm starting to wonder that too, if maybe since my radiator is bigger, but I'm still using the stock fan, if it can't pull enough air through there.
I'm having the thermostat and radiator checked this weekend and if that's not the issue, maybe I'll have to try the fan you mentioned and see if that cures my problem. Thanks for sharing.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Apr 20, 2017
#45
  • Apr 20, 2017
  • #45
plantmeister said:
I'm just watching the dash gauge for the temperature
Click to expand...

Those are known to be quite inaccurate. Not saying it is..but if it's off 10 degrees, then your temps are actually ok.

Do you have an aftermarket temp guage handy? Or even a cheapo parts store gauge?
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 20, 2017
#46
  • Apr 20, 2017
  • #46
Mustang5L5 said:
Those are known to be quite inaccurate. Not saying it is..but if it's off 10 degrees, then your temps are actually ok.

Do you have an aftermarket temp guage handy? Or even a cheapo parts store gauge?
Click to expand...

Really? Okay dang. No, I don't have any other temp gauges, but they sound easy to get ahold of. I'll swing by the parts store and see if I can't get one to check the actual temperature.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Apr 20, 2017
#47
  • Apr 20, 2017
  • #47
plantmeister said:
Really? Okay dang. No, I don't have any other temp gauges, but they sound easy to get ahold of. I'll swing by the parts store and see if I can't get one to check the actual temperature.
Click to expand...

The sender for the dash guage is the small sensor on the very front of the driver's side of the lower intake.


Make sure it's clean and there's a tight connection here. If you get an aftermarket guage, install it here. You can just pull the wire off and let it hang. Dash guage will read nothing, but you are using the other guage anyway
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 20, 2017
#48
  • Apr 20, 2017
  • #48
Mustang5L5 said:
The sender for the dash guage is the small sensor on the very front of the driver's side of the lower intake.


Make sure it's clean and there's a tight connection here. If you get an aftermarket guage, install it here. You can just pull the wire off and let it hang. Dash guage will read nothing, but you are using the other guage anyway
Click to expand...

Oh! I looked at that yesterday because I noticed the black connector part had a split up the side where it fits onto the sensor. I wiggled it and it didn't seem loose, but it could still be causing an issue, I'm not sure.
But okay, thanks for the tip. I'm really interested to see if it's just been the dash all along
 

wgreenlee4

Member
Jun 12, 2011
27
5
14
Apr 23, 2017
#49
  • Apr 23, 2017
  • #49
Also, with the gauge sensor (not the EEC temp sensor), it is grounded through the block. I noticed last week my oil pressure and temperature gauges both were hovering higher than usual with no other side effects. I verified my fan was working properly and coolant level was good. I noticed one of my engine ground wires was not in good shape so I cleaned it up real nice and re fastened it and boom no more "overheating". Gauge reads right in the middle now. So yes check the wiring to the sensor AND engine grounds.

If you want to verify the real temperature you can also use T pins and a volt meter to measure the EEC's temperature gauge (mounted on the black heater core pipes above manifold). The service manual has the voltage/resistance chart to read the temperature.
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 28, 2017
#50
  • Apr 28, 2017
  • #50
Dear all,
After checking all the major stuff on this car, the thermostat was pulled to check it,and lo and behold...my 'helper' had put it on backwards.

I'm both aggravated and face palming right now.
Thanks everyone for the help on this one.
 
Reactions: 5.0specialist and Mustang5L5

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,892
10,550
203
polk county florida
Apr 28, 2017
#51
  • Apr 28, 2017
  • #51
Aahhh, it's the simple things in life that trip us up.
So, all's well now?
Sit your helper down on his roll around mechanic's seat and say
YOUR FIRED!
In your helpers defence, it's an easy thing to do.
 
Reactions: 5.0specialist

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Apr 28, 2017
#52
  • Apr 28, 2017
  • #52
 
Reactions: 5.0specialist and plantmeister

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,892
10,550
203
polk county florida
Apr 28, 2017
#53
  • Apr 28, 2017
  • #53
I need one of them patches
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,231
17,918
224
Massachusetts
Apr 28, 2017
#54
  • Apr 28, 2017
  • #54
Is that a real patch? I need one of those
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 28, 2017
#55
  • Apr 28, 2017
  • #55
karthief said:
Aahhh, it's the simple things in life that trip us up.
So, all's well now?
Sit your helper down on his roll around mechanic's seat and say
YOUR FIRED!
In your helpers defence, it's an easy thing to do.
Click to expand...

I can guarantee I won't be asking him for help anymore. He messed up my timing too at one point, but I've since had it timed.

I'm assuming and hoping this fixes it! I bought a 160F thermostat to replace the 190 and it's going to be put in correctly this time. When the gasket maker cures, we'll fire it up and see how it does. I was advised by another mechanic that in everlasting summer of Florida, a lower thermostat was wise.
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 28, 2017
#56
  • Apr 28, 2017
  • #56
mikestang63 said:
Click to expand...

This is amazing lol
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 28, 2017
#57
  • Apr 28, 2017
  • #57
mikestang63 said:
Click to expand...

This is amazing lol
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,892
10,550
203
polk county florida
Apr 28, 2017
#58
  • Apr 28, 2017
  • #58
You could be ok with a 160 stat but these cars are designed to run 190-200 degrees.
The 160 thermostat theory was good back in the 60's not anymore.
 

plantmeister

Active Member
Dec 17, 2016
87
6
28
FL
Apr 28, 2017
#59
  • Apr 28, 2017
  • #59
karthief said:
You could be ok with a 160 stat but these cars are designed to run 190-200 degrees.
The 160 thermostat theory was good back in the 60's not anymore.
Click to expand...

The thermostat temp seems to be a big debate, from what I've seen. Some say cooler is better, some day hotter is better.
So this particular car is better hovering around the 200 mark?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,892
10,550
203
polk county florida
Apr 28, 2017
#60
  • Apr 28, 2017
  • #60
Factory specs are 195 degrees
 
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