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  • 1965 - 1973 Classic Mustangs -General/Talk-

Heater Coil??

  • Thread starter Thread starter MINT68GT
  • Start date Start date Oct 28, 2009
M

MINT68GT

New Member
Oct 28, 2009
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0
0
Oct 28, 2009
#1
  • Oct 28, 2009
  • #1
Hello,
I have a 1968 Mustang Sprint B, GT. I was wondering if anyone can help with suggestions on coolant leaking from the back of the engine? I have heard it maybe my heater coil. It is leaking on the passenger in between the engine and the firewall. No to little coolant inside.
 

JonK

Member
Jun 6, 2007
276
0
16
Nashville (Smyrna), TN
Oct 28, 2009
#2
  • Oct 28, 2009
  • #2
The heater CORE is on the inside of the firewall behind the glovebox so if it was leaking you passengers floorboard would be wet. You could have a pinhole in one of the heater core hoses, a leaky intake gasket or head gasket. Best bet is to get back there with some degreaser and brushes to get a good clean/dry surface then start it with a bright ligtht to see where the coolant is originating from.
"No to little coolant inside" is confusing, does this mean you do have some on the carpet? If so I'd replace both heater hoses immediately. They're not easy to get to (laying on your back looking up) but if you don't change them soon they could bust and spray 200* coolant on the passengers feet and ruin a lot of your interior quickly. I loosened the clamps at the heater core, moved them out the way and slit the hoses lengthwise with a razor knife and peeled them off the htr. core nipples. If you pull on them you could break the solder on the nipples and they'll leak even with new hoses.
Jon
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Oct 29, 2009
#3
  • Oct 29, 2009
  • #3
JonK said:
The heater CORE is on the inside of the firewall behind the glovebox so if it was leaking you passengers floorboard would be wet. You could have a pinhole in one of the heater core hoses, a leaky intake gasket or head gasket. Best bet is to get back there with some degreaser and brushes to get a good clean/dry surface then start it with a bright ligtht to see where the coolant is originating from.
"No to little coolant inside" is confusing, does this mean you do have some on the carpet? If so I'd replace both heater hoses immediately. They're not easy to get to (laying on your back looking up) but if you don't change them soon they could bust and spray 200* coolant on the passengers feet and ruin a lot of your interior quickly. I loosened the clamps at the heater core, moved them out the way and slit the hoses lengthwise with a razor knife and peeled them off the htr. core nipples. If you pull on them you could break the solder on the nipples and they'll leak even with new hoses.
Jon
Click to expand...

I agree with this. Also, If you are replacing heater hoses, I would go ahead and replace the heater core, since you are already there. They are only about 20-30 bucks.
 
E

ETEL64

Member
Jun 20, 2009
51
0
6
NJ REFUGEE, HOUSTON, TEXAS
Nov 6, 2009
#4
  • Nov 6, 2009
  • #4
A/C Car ? I have a 69 w a/c and it had an issue with leaking coolant. It did not show up on the floor board due to the condensation tube for the a/c which drips it right on top of the exhaust manififold. Tricky huh? Replaced htr core on prev 69(non a/c) and it was a full day job. Pary it is just a hose and heed the being super careful with the nipples.
 

kiwimustang

New Member
Oct 13, 2009
4
0
0
Norflok,Nebraska
Nov 6, 2009
#5
  • Nov 6, 2009
  • #5
I may be wrong in saying this but every one is going on about the heater core, yes that could be true but he has coolant between engine and fire wall. As some one said that could be head gasket but it also could be rear engine frost plugs. As suggested you really need to isolate the leak and pinpoint the origin other wise you could be doing things for nothing. My first look would be the hose also suggested. See if its coming from the hoses them selves behind engine out of the holes in the fire wall for the hoses. What would save you a lot of time is using a radiator pressure tester, you can pump up pressure to check and then release when you want to, it saves starting the engine up and getting it up to pressure. If no leakes in hoses or from heater cool ports then look at the back of the cylinder heads.
 
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