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Easiest, most effective way to find out where my coolant leak is?

  • Thread starter Thread starter 5spd GT
  • Start date Start date Mar 5, 2007

5spd GT

"the 5.0 owns all"
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#1
  • Mar 5, 2007
  • #1
It appears I may have a leak around my intake area, with 111k. I have little puddle all the time under my intake on the block.

I keep having to fill up my coolant reservoir every 3-4 weeks, when the light will come on. How can I find out exactly where it is coming from?

Ideas welcome!
 

03ghoststang

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Jul 16, 2005
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Mar 5, 2007
#2
  • Mar 5, 2007
  • #2
does your intake have the plastic crossover where the T-stat is located?
 

tomustang

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#3
  • Mar 5, 2007
  • #3
it's your intake (t stat housing), you can't repair it since it's composite, you need to replace it with a new one
 

5spd GT

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#4
  • Mar 5, 2007
  • #4
What is this plastic crossover piece, I think I know what you are talking about. Does it look like a little rectangular box?
 

COramprat

...I can take it. I think.
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#5
  • Mar 6, 2007
  • #5
5spd GT said:
What is this plastic crossover piece, I think I know what you are talking about. Does it look like a little rectangular box?
Click to expand...

It is the forward portion of the lower intake. Look where the thermostat housing is and see if you can see moisture. Most of them crack there (Mine did). The replacement piece will have an aluminum crossover much less susceptible to failure.



With aluminum crossover
 

5spd GT

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#6
  • Mar 7, 2007
  • #6
Looks like I'm going to do the pi headswap. I'm getting used heads/cam, but a new intake.

Thanks for the response!
 

kid rock

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Mar 7, 2007
#7
  • Mar 7, 2007
  • #7
good luck with the swap dude, i had the same thing cracked intake with less than 40,000 miles on it! grr oh well, intake swap done now!

Si
 

5spd GT

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#8
  • Mar 7, 2007
  • #8
What can I do to check where the leak is coming from? Have a mechanic pressurize the coolant system?
 

RandyStinchcomb

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#9
  • Mar 8, 2007
  • #9
5spd GT said:
What can I do to check where the leak is coming from? Have a mechanic pressurize the coolant system?
Click to expand...

you can go-to a auto parts store and buy some coolant systen dye and add it to the coolant system, now some coolant system dyes might require the use of a black lite to aid in finding the leak
 

5spd GT

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#10
  • Mar 8, 2007
  • #10
Good idea, I have a black light!
 

Dusstbuster

I love meat more than anything! I just have a spec
May 31, 2004
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Mar 8, 2007
#11
  • Mar 8, 2007
  • #11
Why do you want to find the leak? There is really no way to fix it other than swapping manifolds...plus the new manifold will give you power gains too, unless you just buy an NPI manifold w/ the Aluminum crossover.
 

98bluevert

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#12
  • Mar 8, 2007
  • #12
easiest way if the crossover is cracked is to start the engine then from under the hood pull on the throttle cable and rev it up to about 3500 rpms. should be very noticable then. right behind the alternantor usually.
 

four six

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Jan 19, 2006
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#13
  • Mar 8, 2007
  • #13
5spd GT said:
Have a mechanic pressurize the coolant system?
Click to expand...

No point in doing this. You need a new intake, since your doing the PI swap problem solved.
 

5spd GT

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Mar 9, 2007
#14
  • Mar 9, 2007
  • #14
It is pretty simple really on why I want to find where the leak is coming from:

Because I don't know where it is coming from

It could be the intake, it could be at the radiator, it could be from a hose, blah, blah...

Sure it is more likely from the intake, but do I know that for sure Nope.

I'll do the 3,500 rpm check

Again, thanks guys!
 

forum155pl

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#15
  • Mar 9, 2007
  • #15
when my intake went, i finally found it when i reved it up from underneith the hood.. the leak was a fine stream that you could barely see.. it sprayed about 20 feet out..

the Coolant Dye works very well.. i would dye it and pressure test the system at the same time if you really want to see the leak..
 
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