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Please Help Running Very Hot

  • Thread starter Thread starter Chad91gt
  • Start date Start date Mar 5, 2017
C

Chad91gt

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Mar 2, 2017
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Mar 5, 2017
#1
  • Mar 5, 2017
  • #1
1991 mustang gt. Was running 1-2 notches below red line on temperature.. which is still high.. flushed radiator now runs way above red line.and stays there. But when I start it when car is cold shows it at normal temp. And rises fast. But when use infared on water pump and neck shows 160-170-180.. am I checking the right area with infared? Could it be my thermostat? Or my coolant sensor? No water in oil..No coolant is spilling out of radiator ..
 

General karthief

wonder how much it would cost to ship you a pair
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#2
  • Mar 5, 2017
  • #2
Go buy a cheep manuel temp gauge and install it. Zip tie it to your wiper arm and watch the gauge.
Report back your temp readings,
Just a thought, you said cold temp gauge is at normal? Where is the needle when key is off?
 
C

Chad91gt

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#3
  • Mar 5, 2017
  • #3
karthief said:
Go buy a cheep manuel temp gauge and install it. Zip tie it to your wiper arm and watch the gauge.
Report back your temp readings,
Just a thought, you said cold temp gauge is at normal? Where is the needle when key is off?
Click to expand...
Thanks I'll purchase a cheap guage and see what happens. I meant when I give a little time to cool Then start it the needle will drop.. and if the next day it will be at the bottom like normal. But goes up pretty fast.
 

mikestang63

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#4
  • Mar 6, 2017
  • #4
  • did you burp the system
  • is the thermostsat opening
  • are any hoses collapses
  • is the radiator cap working
 

jrichker

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Does the engine overheat during highway driving or mostly just around town?
 
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Chad91gt

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#6
  • Mar 7, 2017
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So I took out the thermistat.. took forever with the bottom bolt. And I boiled water .once boiling I out thermistat in there for 20-25 seconds. And does not open. This means thermistat is no good. And probably was the problem? Also I ran It hot for 5-10 mins over red line. Wht should I look for if I did any damage to my engine.? I check the oil and there is no coolant in it and no white smoke. No ticking. Engine still sounds good
 

General karthief

wonder how much it would cost to ship you a pair
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#7
  • Mar 7, 2017
  • #7
Put a 195 t stat in and a manuel gauge and see how it does.
Check what mikestang63 said, are you familiar with burping a mustang?
 
H

Hammershop

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#8
  • Mar 7, 2017
  • #8
the 5.0 wasn't as bad as some other ford engines for getting vapor locked but still did,,oem ford thermostats had a small ball bearing valve on them to bleed out the air from the intake side,,I always drill a 1/8 inch hole in aftermarket ones so the air will bleed out ,,doesn't make a difference in warm up or operating temp,,you cant always count on the air bleeding out thru the bypass
 

General karthief

wonder how much it would cost to ship you a pair
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#9
  • Mar 7, 2017
  • #9
Chad91gt said:
So I took out the thermistat.. took forever with the bottom bolt. And I boiled water .once boiling I out thermistat in there for 20-25 seconds. And does not open. This means thermistat is no good. And probably was the problem? Also I ran It hot for 5-10 mins over red line. Wht should I look for if I did any damage to my engine.? I check the oil and there is no coolant in it and no white smoke. No ticking. Engine still sounds good
Click to expand...
Put thermostat in andgo with it your likely ok.
 
H

Hammershop

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#10
  • Mar 7, 2017
  • #10
karthief said:
Put thermostat in andgo with it your likely ok.
Click to expand...
that's what I think too,,nothing like making things more complicated than they are
 
Reactions: General karthief

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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#11
  • Mar 7, 2017
  • #11
Sometimes I over explain things to the point that even I'm confused after.
 
D

Deleted member 215073

Mar 8, 2017
#12
  • Mar 8, 2017
  • #12
Motorcraft thermostats are still available. I picked one up at O'Reilly auto parts recently. Think it was $12. It will only go in with the little ball vent at the top.
 
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Hammershop

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#13
  • Mar 8, 2017
  • #13
youll still have to make sure all the air gets bled out
 

mikestang63

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#14
  • Mar 8, 2017
  • #14
lysle funnel - use it
 

Tremic789

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Mar 11, 2017
#15
  • Mar 11, 2017
  • #15
Chad91gt said:
1991 mustang gt. Was running 1-2 notches below red line on temperature.. which is still high.. flushed radiator now runs way above red line.and stays there. But when I start it when car is cold shows it at normal temp. And rises fast. But when use infared on water pump and neck shows 160-170-180.. am I checking the right area with infared? Could it be my thermostat? Or my coolant sensor? No water in oil..No coolant is spilling out of radiator ..
Click to expand...
Just a question you didnt change the serpentine belt if so is the waterpump turning the right direction. I had that problem with my car i had the pump goin the wrong direction.
 

Tremic789

New Member
Feb 28, 2017
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Mar 11, 2017
#16
  • Mar 11, 2017
  • #16
Chad91gt said:
1991 mustang gt. Was running 1-2 notches below red line on temperature.. which is still high.. flushed radiator now runs way above red line.and stays there. But when I start it when car is cold shows it at normal temp. And rises fast. But when use infared on water pump and neck shows 160-170-180.. am I checking the right area with infared? Could it be my thermostat? Or my coolant sensor? No water in oil..No coolant is spilling out of radiator ..
Click to expand...
Just a question you didnt change the serpentine belt if so is the waterpump turning the right direction. I had that problem with my car i had the pump goin the wrong direction.
 
C

Chad91gt

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Mar 2, 2017
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Mar 11, 2017
#17
  • Mar 11, 2017
  • #17
So I finally changed the thermistat. I put in a 180 tstat. And changed the two hoses that connect to the water pump. Bam...... problem fixed. Doesn't go above half way point when fully warm. Thanks everyone for the help
 

mikestang63

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Aug 27, 2012
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Mar 12, 2017
#18
  • Mar 12, 2017
  • #18
Chad91gt said:
So I finally changed the thermistat. I put in a 180 tstat. And changed the two hoses that connect to the water pump. Bam...... problem fixed. Doesn't go above half way point when fully warm. Thanks everyone for the help
Click to expand...

  • curious why a 180 stat
  • did you burp the air out of the system
 
C

Chad91gt

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Mar 12, 2017
#19
  • Mar 12, 2017
  • #19
Wanted to be more on the safe side . Feel like a lower tstat would make me feel a little better. Dealing with over heating. And I did burp the system. Anyone recommend a specific type of coolant or additive like water wetter
 

mikestang63

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Mar 12, 2017
#20
  • Mar 12, 2017
  • #20
ok. but a lower stat does not control the operating temperature.
dont use anything but coolant and distilled water. 50/50 works for most climates in the south you can use 70/30 water to coolant
you installed the stat with the spring facing the motor
 
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