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Coolant Leak I Can't Find

  • Thread starter Thread starter QuietOne
  • Start date Start date Jul 19, 2017
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QuietOne

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Jul 19, 2017
#1
  • Jul 19, 2017
  • #1
On the way home today I started leaking coolant. It's behind the intake, in the middle of the engine bay. I can't see it from the top. It's hissing and leaking down onto the bellhousing then onto the floor.

Any ideas?

@FoxMustangLvr @hoopty5.0 @karthief @tannerc91gt
 

FoxMustangLvr

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#2
  • Jul 19, 2017
  • #2
QuietOne said:
On the way home today I started leaking coolant. It's behind the intake, in the middle of the engine bay. I can't see it from the top. It's hissing and leaking down onto the bellhousing then onto the floor.

Any ideas?

@FoxMustangLvr @hoopty5.0 @karthief @tannerc91gt
Click to expand...
Check where your heater hoses from the firewall connect to your heater pipe. There is two of them.
 
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FoxMustangLvr

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#3
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If it's not the those hoses then it's possible that you're leaking from the back of the lower intake where it mates to the engine block.
 
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RaggedGT

Been here over a DECADE and still no CT
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Sure it's not a freeze out plug on the back of the cylinder head?
 
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QuietOne

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RaggedGT said:
Sure it's not a freeze out plug on the back of the cylinder head?
Click to expand...
I 100% believe it is a hose because when it's under pressure it sprays a small stream against the firewall. It leaked about a cup once I got it in the garage now it's not leaking at all. The top side of the heater hoses where they plug into the heater core look to be in good shape. Most of the other hoses had pin holes near an attachment points.
 
Last edited: Jul 19, 2017
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FoxMustangLvr

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QuietOne said:
I 100% believe it is a hose because when it's under pressure it sprays a small stream against the firewall. It leaked about a cup once I got it in the garage now it's not leaking at all. The top side of the heater hoses where they plug into the heater core look to be in good shape. Most of the other hoses had pin holes near an attachment points.
Click to expand...
If you are going to replace those hoses then make sure you use a hose tool to loosen the connection of the hose to the pipe. A lot of people try to muscle them off and end up breaking their heater core pipes at the firewall or you could slice them open with a razor blade and peel them off.


Edit: Mine were leaking not too long ago. My hoses are brand new so all I had to do was just tighten the hose clamps just a bit more and the leak stopped.
 
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mikestang63

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go to autozone or advanced auto and for free rent a coolant pressure tester. Whn the car is cool, remove the cap, use the appropriate adapter and pump up the pressure to 16#.. If you have a leak you should see it fairly easy and the pressure will drop. If a small leak, the pressure will drop gradually over time. A normal cooling system should maintain the 16# for at least an hour with no drop in pressure.

If you have a leak in one of the small heater hoses going to the firewall or from the water pump to the intake, it is easier to use a razor blade and make a cut lengthwise to remove them, rather than try and pry them off. You won't risk breaking off the fittings that way and it is plain easier than wrangling them off in the tight quarters..
 
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QuietOne

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Jul 24, 2017
#8
  • Jul 24, 2017
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So I go to put coolant in the Fox today to drive it down to the shop for said coolant leak issues. Now there is coolant dripping down the front of the engine too. About ready to set this thing on fire!
 

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Jul 24, 2017
#9
  • Jul 24, 2017
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Worm gear clamps 'might' be the problem.IMO these are far better... http://6364cadillac.ning.com/profiles/blogs/tower-hose-clamps
 

revhead347

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#10
  • Jul 24, 2017
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mikestang63 said:
go to autozone or advanced auto and for free rent a coolant pressure tester. Whn the car is cool, remove the cap, use the appropriate adapter and pump up the pressure to 16#.. If you have a leak you should see it fairly easy and the pressure will drop. If a small leak, the pressure will drop gradually over time. A normal cooling system should maintain the 16# for at least an hour with no drop in pressure.

If you have a leak in one of the small heater hoses going to the firewall or from the water pump to the intake, it is easier to use a razor blade and make a cut lengthwise to remove them, rather than try and pry them off. You won't risk breaking off the fittings that way and it is plain easier than wrangling them off in the tight quarters..
Click to expand...

Absolutely. Pressurize the system with a cold car so you can get your hands in there without burning them off. Always cut a hose off a heater core. Why would you try and save a hose you are going to replace anyway?

Kurt
 

QuietOne

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#11
  • Jul 25, 2017
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Got it down to the shop. Replacing all hoses, water pump and timing cover. Water pump has a ton of rust in it. Timing cover is warped, broke a few bolts too.
 

RaggedGT

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#12
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Replace the timing chain while you have the cover off
 
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FoxMustangLvr

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RaggedGT said:
Replace the timing chain while you have the cover off
Click to expand...
May as well upgrade the cam while your replacing the timing chain while your already replacing the cover anyways......
 
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RaggedGT

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  • Jul 25, 2017
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FoxMustangLvr said:
May as well upgrade the cam while your replacing the timing chain while your already replacing the cover anyways......
Click to expand...

Good thinking
 
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QuietOne

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Jul 25, 2017
#15
  • Jul 25, 2017
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I thought about all this however I can't afford it at the moment lol
 
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mikestang63

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  • Jul 25, 2017
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FoxMustangLvr said:
May as well upgrade the cam while your replacing the timing chain while your already replacing the cover anyways......
Click to expand...

good time to swap the intake and heads too
 
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QuietOne

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#17
  • Jul 25, 2017
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mikestang63 said:
good time to swap the intake and heads too
Click to expand...
Stop it! Oh getting a new radiator too
 

FoxMustangLvr

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#18
  • Jul 26, 2017
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QuietOne said:
Stop it! Oh getting a new radiator too
Click to expand...
New radiator That's good for at least +25hp
 

Ryuk

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  • Jul 26, 2017
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If you've got the radiator out, might as well switch to an electric fan.
 

QuietOne

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#20
  • Aug 2, 2017
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Back on the road. Entire coolant system replaced.
 
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