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  • SN95 4.6L Mustang Tech

Coolant/Radiator leak

  • Thread starter Thread starter Donovaldez
  • Start date Start date Jan 22, 2023
D

Donovaldez

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Jan 22, 2023
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  • Jan 22, 2023
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My 04 gt has a small coolant leak but no overheating. I flushed the coolant and everything with new top radiator hose. Still leaks a little I think it’s a cracked radiator. Smoke coming from right below top radiator hose on passenger side.
 

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D

Donovaldez

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  • Jan 22, 2023
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Asking to see if someone can help me out
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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Jan 23, 2023
#3
  • Jan 23, 2023
  • #3
If you were closer I would help you yank that radiator and replace it with a new one, shop around like RockAuto and 1-800Radiator, autozone. Most radiators have plastic tanks now and over time leak at the seam, my toyota has been seeping for a year, come to think of it, if I'm not fixing mine, I doubt I'm helping R&R yours, I will come over, drink your whisky and point at stuff and say "you should fix that", you know useful stuff
 
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Donovaldez

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  • Jan 23, 2023
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General karthief said:
If you were closer I would help you yank that radiator and replace it with a new one, shop around like RockAuto and 1-800Radiator, autozone. Most radiators have plastic tanks now and over time leak at the seam, my toyota has been seeping for a year, come to think of it, if I'm not fixing mine, I doubt I'm helping R&R yours, I will come over, drink your whisky and point at stuff and say "you should fix that", you know useful stuff
Click to expand...
So it's most likely the radiator correct?
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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Jan 23, 2023
#5
  • Jan 23, 2023
  • #5
From the pics I would guess yes but I'm not there to really poke around, you're gonna have to take it out to get a look.
 
D

Deleted member 38176

Jan 24, 2023
#6
  • Jan 24, 2023
  • #6
Replace the radiator
 
Reactions: Shuttleman83

manicmechanic007

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Jan 26, 2023
#7
  • Jan 26, 2023
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Clean it all off and reposition the radiator clamps and try it again?
Those clamps are too far from the radiator and are on the very end of the hose nipple
They are supposed to be right behind the nipple
Alright yes replace the leaking radiator too after the recheck
 
D

Donovaldez

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  • Jan 26, 2023
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manicmechanic007 said:
Clean it all off and reposition the radiator clamps and try it again?
Those clamps are too far from the radiator and are on the very end of the hose nipple
They are supposed to be right behind the nipple
Alright yes replace the leaking radiator too after the recheck
Click to expand...
By clamps you mean the radiator hoses right? I’m pretty sure coolant is seeping through cracks in the radiator, here’s a better picture after I warmed up my Stang and coolant started to slowly leak
 

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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
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polk county florida
Jan 26, 2023
#9
  • Jan 26, 2023
  • #9
Any rust stains around the radiator cap?
 

manicmechanic007

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#10
  • Jan 27, 2023
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Yes, It looks like the plastic side tank leaks (the plastic cracks often and the gaskets leak)
Flush that cooling system with the Ford flush to get the rust out
Rust that bad will eat out the freeze plugs
Flush is bad stuff / caustic
Flush it with the old radiator in it maybe
I mentioned the clamps position just so you know
Big fan of solid aluminum radiators myself with no side tanks
If cost is an issue just go stock and call someone like 1800radiator
 
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General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,868
10,542
203
polk county florida
Jan 27, 2023
#11
  • Jan 27, 2023
  • #11
If your freez plugs (sometimes called 'core plugs' ) are marginal that Ford flush stuff may cause them to start leaking, which can be a good thing.
Yes, it is very caustic. I used it on an engine before I pulled it and swapped all the core plugs, you gotta flush it with fresh water several times.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Jan 27, 2023
#12
  • Jan 27, 2023
  • #12
You can rent a pressure tester for the coolant system, which will pressurize it and show you leaks, if there are any.

Based on those photos however, i would guess a new rad is in your future. I would just want to verify it's not bypassing the hose clamp and coming out there first.
 
S

Shuttleman83

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Jun 30, 2019
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Jan 27, 2023
#13
  • Jan 27, 2023
  • #13
There is a high pressure JB Water Weld that can sometimes work for a short duration, possibly a bit longer depending on how skilled you are. Not too expensive.
 
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Donovaldez

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Jan 22, 2023
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Jan 28, 2023
#14
  • Jan 28, 2023
  • #14
manicmechanic007 said:
Yes, It looks like the plastic side tank leaks (the plastic cracks often and the gaskets leak)
Flush that cooling system with the Ford flush to get the rust out
Rust that bad will eat out the freeze plugs
Flush is bad stuff / caustic
Flush it with the old radiator in it maybe
I mentioned the clamps position just so you know
Big fan of solid aluminum radiators myself with no side tanks
If cost is an issue just go stock and call someone like 1800radiator
Click to expand...
I replaced the radiator but it’s still smoking but I found where it coming from. It’s just coming from the ac hose right where u insert the Freon in. Is there an easy way to fix it or do I have to replace the whole hose?
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,216
17,899
224
Massachusetts
Jan 28, 2023
#15
  • Jan 28, 2023
  • #15
Gotta replace entire line
 
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