Possible heater core leak
Thread Starter
Instructor
Joined: Jul 2007
Posts: 141
Likes: 14
Possible heater core leak
Looking for any suggestions / recommendations. After taking my 64 / no AC car out for a drive yesterday, some letter size paper I had placed on the drivers side carpet was fairly damp. Obvious thought is a leak in the heater core. I can't think of anything else causing the issue. Would a pressure test of the cooling system help verify a leak? Would members suggest by-passing the heater core for now since I seldom use the heater unless I'm in a stop-and-go driving situation on a hot day to help the cooling system? Anyone ever replaced the core on a 64?
Thanks guys.
Thanks guys.
Melting Slicks
Joined: Jul 2006
Posts: 2,346
Likes: 41
From: Toronto
Heater core is on the passenger side. Did you mean the paper that got wet was on the passenger side, not drivers?
You could bypass the heater core since you don't use it. That would be a lot easier than replacing it. It can be replaced but it's a pain to do. Do a search for heater core to see how to change it out.
You could bypass the heater core since you don't use it. That would be a lot easier than replacing it. It can be replaced but it's a pain to do. Do a search for heater core to see how to change it out.
Thread Starter
Instructor
Joined: Jul 2007
Posts: 141
Likes: 14
Thanks for the response hzz. Yes papers were on passenger side where the heater core is. After I posted my question I noticed a recent good thread about a using a McMaster-Carr check valve. Sounds like a good idea that would work.
Latest example of great info on the Forum and members willing to share.
Latest example of great info on the Forum and members willing to share.
Instructor
Joined: Nov 2002
Posts: 105
Likes: 0
From: Southern Pines nc
If you don't need the heat by pass it, very simple to do. The heater core replacement is a PIA and you should get a good rebuild kit like Dr Rebuild's and go through the whole box while you have it apart. If your heater box is a virgin your seals are going to be shot anyway.
Pete
Pete
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
If you're going to use a shutoff valve to "bypass" the heater core as discussed in a recent thread, you'll need two valves, one in each hose or the coolant will back feed into the core and you'll still have a leak.
I changed out the original heater core in my '63 a few years ago because it sprung a leak. The new one lasted about a year or two and it started to leak so I dumped a small bottle of Barr's Stop Leak in it and it stopped the leak almost instantly. It's been fine for a year now and I don't anticipate any trouble out of it again.
You can do what you want but I don't think it's too much trouble to change the heater core in a non-AC car. It'll give you something to do on a rainy afternoon.
I changed out the original heater core in my '63 a few years ago because it sprung a leak. The new one lasted about a year or two and it started to leak so I dumped a small bottle of Barr's Stop Leak in it and it stopped the leak almost instantly. It's been fine for a year now and I don't anticipate any trouble out of it again.
You can do what you want but I don't think it's too much trouble to change the heater core in a non-AC car. It'll give you something to do on a rainy afternoon.
Le Mans Master
Joined: Sep 2008
Posts: 5,660
Likes: 2,344
From: Lake Minnetonka, Mn
2018 C1 of Year Finalist
If you're going to use a shutoff valve to "bypass" the heater core as discussed in a recent thread, you'll need two valves, one in each hose or the coolant will back feed into the core and you'll still have a leak.
I changed out the original heater core in my '63 a few years ago because it sprung a leak. The new one lasted about a year or two and it started to leak so I dumped a small bottle of Barr's Stop Leak in it and it stopped the leak almost instantly. It's been fine for a year now and I don't anticipate any trouble out of it again.
You can do what you want but I don't think it's too much trouble to change the heater core in a non-AC car. It'll give you something to do on a rainy afternoon.
I changed out the original heater core in my '63 a few years ago because it sprung a leak. The new one lasted about a year or two and it started to leak so I dumped a small bottle of Barr's Stop Leak in it and it stopped the leak almost instantly. It's been fine for a year now and I don't anticipate any trouble out of it again.
You can do what you want but I don't think it's too much trouble to change the heater core in a non-AC car. It'll give you something to do on a rainy afternoon.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,873
From: Greenville, Indiana
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Melting Slicks
Joined: Aug 2006
Posts: 2,607
Likes: 374
From: Oceanside CA
You should be able to tell if you have coolant on the paper by color or smell. Did you recently wash your car? There is a drain from the cowl to the bottom of the car. If it is plugged, you can get water through the passenger side vent. I have replaced the heater core on my a/c '64 and it is a pia.
Tech Contributor
Joined: May 2005
Posts: 15,573
Likes: 117
From: Conroe Texas
I'd throw a bottle of Bar's Leak Stop at it first, see if you have success there. Can save you a lot of time and hassle until you are more motivated to dig into the heater core replacement.
I hear replacing the heater core on a non-A/C car sucks, but less than in an A/C car.
I hear replacing the heater core on a non-A/C car sucks, but less than in an A/C car.
Le Mans Master
Joined: Jun 2004
Posts: 9,015
Likes: 331
From: Southeast Missouri
It's a pretty good job, OK. I've had mine out 2-3 times over the years and always dread it. Never wants to come apart or go back together until you get it into the "just right" position.
My heater core is OK, has been for 35++ years, but every now & again when I replace the battery I make the mistake of pulling on the heater hoses to get them out of the way, and this will break loose the inlet or outlet tube to the core. I used stop leak in mine for a few years until this summer when it started leaking again & I decided it was time to bite the bullet.
Yours may well be leaking at one of the inlet/outlet tubes, that's a common problem. It's also an easy fix once the core is removed, any radiator shop should be able to test the core to see where it's leaking and to re-solder the tube should that happen to be the source of the leak.
My heater core is OK, has been for 35++ years, but every now & again when I replace the battery I make the mistake of pulling on the heater hoses to get them out of the way, and this will break loose the inlet or outlet tube to the core. I used stop leak in mine for a few years until this summer when it started leaking again & I decided it was time to bite the bullet.
Yours may well be leaking at one of the inlet/outlet tubes, that's a common problem. It's also an easy fix once the core is removed, any radiator shop should be able to test the core to see where it's leaking and to re-solder the tube should that happen to be the source of the leak.
Racer
Joined: Jun 2007
Posts: 281
Likes: 1
From: Springfield MO
Bypass for now and fix it this winter. It is not an easy job but is time conusming and you will want to do other things while you are there.
Thread Starter
Instructor
Joined: Jul 2007
Posts: 141
Likes: 14
Thanks everyone for their responses. The thing that had me puzzled was there were no marks on the paper like coolant or the small. But it's had to think it was something else. Ordered the cutoff valve from McMaster already for the 5/8" core intake hose and will install right away. Will also try some stop leak.
Probably will pull the core as a winter project. In Buffalo that gives me about five months to complete, give or take a month.
Thanks again.
Probably will pull the core as a winter project. In Buffalo that gives me about five months to complete, give or take a month.
Thanks again.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,873
From: Greenville, Indiana
If you use the stop leak, you won't need the valves. If you use the valves, you don't need the stop leak.
