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Engine Mustang cooling and temps

  • Thread starter Thread starter amkullar
  • Start date Start date Jun 11, 2021
A

amkullar

Member
Apr 24, 2019
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Vancouver bc
Jun 11, 2021
#1
  • Jun 11, 2021
  • #1
Hey Guys. Foxbody temp and cooling question.
Have a 306 with HCI, 24 lb Injectors, 180 T Stat and I just installed a Fkex a lite 185 and have a year old SVE 3 Row Aluminum rad. The car when idling is fine. Fan turn in at 185 hit 187 and cool down to 177 area. When I start driving the temps start to climb hit about 200-207. Won't come down until I get to an idle and it just sitting there idling or I let off the throttle. I bled the cooling system with a Lysle Funnel and have the air out of the system. Trying to figure out what I need to look at? It's a GT so air flow is restricted a bit. The air damp plastic pieces are still there. The fan is suckling in air. The car has a Alt and Water pump underdrive pulley but stock crank pulley. Should I change out the water pump pulley?
Timing? Water pump? Not sure where to look next. Any help is appreciated
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Massachusetts
Jun 11, 2021
#2
  • Jun 11, 2021
  • #2
Does it cool on the highway at a steady cruise or does it still run hot? Sounds like it could be an airflow issue if that's the case.

DO you have the radiator side deflectors in place? Are the fins on the radiator clear and free of debris?
 
A

amkullar

Member
Apr 24, 2019
32
3
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Vancouver bc
Jun 11, 2021
#3
  • Jun 11, 2021
  • #3
On the highway it runs hot unless I'm off the throttle. If it's just coasting it starts to cool down. But one I'm back on the throttle it stops cooling down. I have the air reflectors on the side. The rad is clean. No debris and I flushed the whole thing
 

jrichker

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#4
  • Jun 11, 2021
  • #4
Is the air dam under the radiator in place and not busted?
It is the first that that gets hit under the car if you run over any kind of solid object.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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Jun 11, 2021
#5
  • Jun 11, 2021
  • #5
Also timing advanced too far can make an engine run hot at speed but I'm leaning toward air and/or coolent flow issue
 
A

amkullar

Member
Apr 24, 2019
32
3
18
Vancouver bc
Jun 11, 2021
#6
  • Jun 11, 2021
  • #6
Air damn is still there. Thinking maybe switch out water pomp and do a stock water pump pulley. It was a new T stat in April but I can change it again if need be. It's a new motor. Has been runny fine within temps. Had the first super hot day and the sve dial fans weren't doing much. Bought a flex a lite fan having same issue
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,236
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Massachusetts
Jun 11, 2021
#7
  • Jun 11, 2021
  • #7
Inwould pressure test the system first and verify the pressure cap is working properly
 
Reactions: General karthief

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
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Jun 11, 2021
#8
  • Jun 11, 2021
  • #8
Yes put the stock water pump pulley and alternator pulleys back on. More coolant flow and more alternator output can’t do anything but help your situation.
 

2000xp8

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Aug 8, 2003
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Jun 12, 2021
#9
  • Jun 12, 2021
  • #9
The pulley and water pump most likely won't solve it (assuming the right water pump is installed and you can see coolant moving with the radiator cap off).
At speed it should be moving plenty of coolant and it's not like water pumps break and somewhat work.
It either works or doesn't. The fans don't do much on the highway so i wouldn't be worried about the fan..

I agree with mike, pressure test it. Sounds to me like maybe somehow air is still in the system or getting back in there.
 
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