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  • 1996 - 2004 SN95 Mustang -General/Talk-

Coolant Leak From Temp Sensor

  • Thread starter Thread starter GT99BLACK
  • Start date Start date Feb 27, 2014

GT99BLACK

Member
Apr 15, 2012
31
1
9
Feb 27, 2014
#1
  • Feb 27, 2014
  • #1
I searched but was unable to find this issue. I am noticing what appears to be a coolant leak from the coolant temp sensor on the coolant crossover. It appears the coolant is spraying out of the sensor threads and getting on the alternator. I have the aluminum crossover and installed a new sensor recently using red permatex thread lock. I was wondering if anyone has had this problem or could lead me in the right direction to fix it. I am having a new radiator installed soon but want to make sure I address this issue at the same time.



Thank you for reading.
 

Mattstang04

15 Year Member
Sep 15, 2006
1,152
144
104
St. Louis, MO
Mar 7, 2014
#2
  • Mar 7, 2014
  • #2
Make sure it isn't coming from underneath the intake crossover. Cracked intakes are common place in these cars. There are a lot of us who have already replaced them once. Have a look underneath and in the area behind the crossover. Hate to be the bearer of bad news but you are likely heading in that direction.
 
A

adamv7010

Member
Feb 18, 2014
43
2
19
Mar 7, 2014
#3
  • Mar 7, 2014
  • #3
Mattstang04 said:
Make sure it isn't coming from underneath the intake crossover. Cracked intakes are common place in these cars. There are a lot of us who have already replaced them once. Have a look underneath and in the area behind the crossover. Hate to be the bearer of bad news but you are likely heading in that direction.
Click to expand...
This...that's exactly where mine leaked
 
D

Deleted member 38176

Mar 7, 2014
#4
  • Mar 7, 2014
  • #4
The cracked intake is a right of passage in the mod motor world, so-to-speak. There are no "fixes" for this. Entire intake needs to be replaced.
 

GT99BLACK

Member
Apr 15, 2012
31
1
9
Mar 9, 2014
#5
  • Mar 9, 2014
  • #5
Thanks for all of the replies. I found a permatex for high heat/high pressure but took some pics and may need to fix something else first. First pic should be where you can see coolant residue near temp sensor/threads, second should be behind alt. Looks bad can anyone confirm what needs to be replaced?
 
Reactions: Suek

Mattstang04

15 Year Member
Sep 15, 2006
1,152
144
104
St. Louis, MO
Mar 11, 2014
#6
  • Mar 11, 2014
  • #6
If the intake is not leaking, there is a coolant line that runs from behind the waterpump through the center of the valley, to the rear of the engine. There have been instances where the nipple on the inside of the valley, behind the water pump, that the coolant line connects to has leaked. Also the coolant line itself could be leaking. Most of the time it is the intake though.
 

GT99BLACK

Member
Apr 15, 2012
31
1
9
Mar 13, 2014
#7
  • Mar 13, 2014
  • #7
Mattstang04 said:
If the intake is not leaking, there is a coolant line that runs from behind the waterpump through the center of the valley, to the rear of the engine. There have been instances where the nipple on the inside of the valley, behind the water pump, that the coolant line connects to has leaked. Also the coolant line itself could be leaking. Most of the time it is the intake though.
Click to expand...

The coolant in the valley evaporated so I re installed the coolant temp sensor with the correct sealant. Ran/drove the car for an hour, no leak. I am pretty sure if it was the intake manifold was the issue, there would have been a leak. I am going to drive it the rest of the week and see if the coolant pools up in the valley again. Thanks for the help.
 
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