1970 w/ AC Heater Core: Just Failed
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
1970 w/ AC Heater Core: Just Failed
This just happened on a very hot day here in New Brunswick. I noticed some coolant on the garage floor and saw some condensation behind my passenger side floor mat. Stuck a finger back there and found a little coolant.
I've dreaded this day, for obvious reasons, but I think the thing is probably original so it was inevitable.
This comes at an extra bad time - I'm about to be away from the car for about a year, so I won't have the time to properly remove and replace the core. Can I drain the core and bypass it so it's not leaking while sitting in my garage this fall and winter? I have nice new GM reproduction hoses, etc., on there and I'd like to save those, or at least do something that can't be seen.
I looked at older threads on this, but I wanted to start my own. Thanks in advance.
I've dreaded this day, for obvious reasons, but I think the thing is probably original so it was inevitable.
This comes at an extra bad time - I'm about to be away from the car for about a year, so I won't have the time to properly remove and replace the core. Can I drain the core and bypass it so it's not leaking while sitting in my garage this fall and winter? I have nice new GM reproduction hoses, etc., on there and I'd like to save those, or at least do something that can't be seen.
I looked at older threads on this, but I wanted to start my own. Thanks in advance.
Drifting
Joined: Aug 1999
Posts: 1,451
Likes: 84
From: Round Rock TX
This just happened on a very hot day here in New Brunswick. I noticed some coolant on the garage floor and saw some condensation behind my passenger side floor mat. Stuck a finger back there and found a little coolant.
I've dreaded this day, for obvious reasons, but I think the thing is probably original so it was inevitable.
This comes at an extra bad time - I'm about to be away from the car for about a year, so I won't have the time to properly remove and replace the core. Can I drain the core and bypass it so it's not leaking while sitting in my garage this fall and winter? I have nice new GM reproduction hoses, etc., on there and I'd like to save those, or at least do something that can't be seen.
I looked at older threads on this, but I wanted to start my own. Thanks in advance.
I've dreaded this day, for obvious reasons, but I think the thing is probably original so it was inevitable.
This comes at an extra bad time - I'm about to be away from the car for about a year, so I won't have the time to properly remove and replace the core. Can I drain the core and bypass it so it's not leaking while sitting in my garage this fall and winter? I have nice new GM reproduction hoses, etc., on there and I'd like to save those, or at least do something that can't be seen.
I looked at older threads on this, but I wanted to start my own. Thanks in advance.
Racer
Joined: Sep 2012
Posts: 322
Likes: 11
From: Staten Island New York
A few years ago my core went. I picked up a bypass at the local parts house. I just removed the two heater hoses at the heater core, put the bypass into the hoses. Tighted up the clamps and I was good to go.
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
One heater hose is 5/8" and the other is 3/4".
If you disconnect the hoses at the core you can connect them together with an 'adapter' and not damage your hoses.
Or you can loop the 5/8" hose from the water pump to the manifold. That is a temporary fix which lets you drive a little more before you park it.
If you disconnect the hoses at the core you can connect them together with an 'adapter' and not damage your hoses.
Or you can loop the 5/8" hose from the water pump to the manifold. That is a temporary fix which lets you drive a little more before you park it.
Le Mans Master
Joined: Nov 2016
Posts: 9,279
Likes: 951
From: Lake Tahoe, CA
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
Just unscrew the pipe nipple in the intake and the one in the water pump and put pipe plugs where the nipples were. Your total investment will be about two bucks. You can get super fancy and use hex-drive plugs for a flush fit or go to your local home improvement center's plumbing section and pay the two bucks for the pipe plugs. This takes the hoses completely out of the mix.
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 787
From: Lebanon Township New Jersey
Just unscrew the pipe nipple in the intake and the one in the water pump and put pipe plugs where the nipples were. Your total investment will be about two bucks. You can get super fancy and use hex-drive plugs for a flush fit or go to your local home improvement center's plumbing section and pay the two bucks for the pipe plugs. This takes the hoses completely out of the mix.
This is the way to go. No bypass hose is needed.
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Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Just unscrew the pipe nipple in the intake and the one in the water pump and put pipe plugs where the nipples were. Your total investment will be about two bucks. You can get super fancy and use hex-drive plugs for a flush fit or go to your local home improvement center's plumbing section and pay the two bucks for the pipe plugs. This takes the hoses completely out of the mix.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
Thanks - it does give a little more confidence. My dash components are mostly original and in great shape - so I worry about damaging something when I dig in there. Never have been a big fan of going into the dash area for that reason.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Just pop the hoses off the core, and install this between them.
https://shop.advanceautoparts.com/p/...yABEgLr3fD_BwE
After you change the core, slip them back on.
https://shop.advanceautoparts.com/p/...yABEgLr3fD_BwE
After you change the core, slip them back on.
