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Heater Coolant Tube Leaking on Lower Intake

  • Thread starter Thread starter 5spd GT
  • Start date Start date Oct 27, 2011

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
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99
Arkansas
Oct 27, 2011
#1
  • Oct 27, 2011
  • #1
Does anyone have any ideas where to get a new o-ring for the heater coolant tube on the lower intake? It is leaking at the rotating portion above the nut.

Thanks for any ideas.
 

4G-KDMP

10 Year Member
Jul 23, 2005
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CA
Oct 27, 2011
#2
  • Oct 27, 2011
  • #2
That I know of there is no O-ring on any part of the heater tube.

Between the upper portion of the heater tube where it attaches to the lower portion that attaches to the intake it is sealed by the red thread sealer and not any sort of O-ring .
 

Boydster

5 Year Member
Apr 10, 2011
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Maryville, Tenn
Oct 27, 2011
#3
  • Oct 27, 2011
  • #3
You're talking about where the big nut threads into the lower intake? That's a swaged flange... no oring. Probably requires replacement of the heater tube.
 

5spd GT

"the 5.0 owns all"
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Oct 27, 2011
#4
  • Oct 27, 2011
  • #4
There is an o-ring above the nut you grab to thread it into the intake. It pivots above the "nut" (1 1/16" or so).

It threads into the intake with thread sealer, yes, but it pivots at the top into the actual tube so it can turn freely.

It is leaking above the nut and a big at the thread in the intake. I know how to fix the thread, but want ideas on the o-ring up in the heater tube above the thread and nut.
 

4rdnut

Member
Dec 14, 2010
188
1
16
Oct 28, 2011
#5
  • Oct 28, 2011
  • #5
o-rings are o-rings, taylors hardware store by me has a huge selection of o-rings, just bring the heater fitting with you and match one up that fits.
 

5spd GT

"the 5.0 owns all"
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Oct 28, 2011
#6
  • Oct 28, 2011
  • #6
I had thought that way 4rdnut - I just prefer to get THE original part.

I may just hit the hardware store up.
 

5spd GT

"the 5.0 owns all"
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Nov 9, 2011
#7
  • Nov 9, 2011
  • #7
Well, tried the O-ring thing out and still got a leak. Any place to get these for less than $100 NEW?
 

ALMOST STOCK

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Sep 23, 2000
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Nov 9, 2011
#8
  • Nov 9, 2011
  • #8
5spd GT said:
Well, tried the O-ring thing out and still got a leak. Any place to get these for less than $100 NEW?
Click to expand...

Being the original owner of my 89 and when polished all the aluminum parts on my engine I had my heater tube chromed I don’t ever remember seeing any O-ring on the heater tube (between the upper and lower nut or any where else), and I never installed an O-ring when I reinstalled the heater tube either and I’ve never had a leak so I’m really curious where this O-ring is suppose to go?

Last weekend I help a good friend pull his engine and when removing the heater tube I specifically looked and then asked my friend to look for an O-ring somewhere on this heater tube that you’ve talked about. Neither he nor I could find any O-ring, but we both agreed the end from the top heater tube had a swagged flange that shows up in the bottom portion of the nut that screws into the lower intake as Boydster had mentioned.

Any pics of where this so-called O-ring goes would be very appreciative.

Thank in advance…
 

5spd GT

"the 5.0 owns all"
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Nov 9, 2011
#9
  • Nov 9, 2011
  • #9
ALMOST STOCK said:
Being the original owner of my 89 and when polished all the aluminum parts on my engine I had my heater tube chromed I don’t ever remember seeing any O-ring on the heater tube (between the upper and lower nut or any where else), and I never installed an O-ring when I reinstalled the heater tube either and I’ve never had a leak so I’m really curious where this O-ring is suppose to go?

Last weekend I help a good friend pull his engine and when removing the heater tube I specifically looked and then asked my friend to look for an O-ring somewhere on this heater tube that you’ve talked about. Neither he nor I could find any O-ring, but we both agreed the end from the top heater tube had a swagged flange that shows up in the bottom portion of the nut that screws into the lower intake as Boydster had mentioned.

Any pics of where this so-called O-ring goes would be very appreciative.

Thank in advance…
Click to expand...

My response was based on a thread I saw with Michael Yount. He said there was an o-ring (along with another) in heater tube. I looked on mine and did not see one either.
 
V

vertvert

Member
Nov 3, 2011
27
0
11
Nov 10, 2011
#10
  • Nov 10, 2011
  • #10
4rdnut said:
o-rings are o-rings, taylors hardware store by me has a huge selection of o-rings, just bring the heater fitting with you and match one up that fits.
Click to expand...

News Flash: Orings are not created equal. There are several types of materials used in orings for different applications. For example some orings will completely fall apart when used in an automotive application when they come in contact with petroleum products. Etc. Etc.

To OP are you sure there is an oring on your heater tube? I can't find one on mine.
 
A

ajhale

New Member
Jul 10, 2003
1
0
2
Sep 8, 2013
#11
  • Sep 8, 2013
  • #11
5spd Gt, what did you end up doing to fix your leak?

I am putting this coolant pipe back on my 94gt after being down for over 6 months while I've been slowly swapping the engine. It just doesn't feel right as I thread the nut into the intake. I can still wiggle the pipe up and down after the nut is tight so it seems like coolant will be able to flow between the pipe and the nut as it is now (nothing for the pipe to bottom out on like a flare fitting would).

How should this thing fit?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Sep 8, 2013
#12
  • Sep 8, 2013
  • #12
Yes, there are o-rings.

http://www.stangnet.com/mustang-for...pair-your-leaky-coolant-hardline-pics.866543/
 
J

jAEded

Active Member
Aug 12, 2013
418
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Cali
Sep 8, 2013
#13
  • Sep 8, 2013
  • #13
liljoe07 said:
Yes, there are o-rings.

http://www.stangnet.com/mustang-for...pair-your-leaky-coolant-hardline-pics.866543/
Click to expand...


I always wondered how that sealed.
 
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