Heater Core Leak Symptom
Thread Starter
Heel & Toe
Joined: Jul 2008
Posts: 22
Likes: 0
From: Steamboat Springs CO
Heater Core Leak Symptom
I think I have a leak from the heater core on my 1980 C-3. Coolant is leaking from the A/C "box" in the engine compartment. Is there any way to make sure it is the core actually leaking without removing the A/C box?
BTW, the A/C components are removed (compressor/condenser/etc.) Is heater core replacement any easier in this case?
BTW, the A/C components are removed (compressor/condenser/etc.) Is heater core replacement any easier in this case?
Racer
Joined: Jan 2007
Posts: 334
Likes: 0
From: York PA
If the leak is the color of your antifreeze then I'd say its either one or both of the hoses (in or out) to your heater core or// the copper sleeves that the hoses connect to. They're about 8 in long and are brazed to the heater core itself. Maybe the brazing split or maybe the hose connections became brittle on the ends where they are clamped to the sleeves. If it were the heater core itself, like the others say, then it would be leaking inside on your passenger floor mat. Only other thing that may be leaking is condensate from the AC accumulator. chuck
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Are you losing coolant? Can you smell anti-freeze? A bad heater core almost always leaks into the passenger side floor board, BUT stranger things have happened.
Major PITA to swap an AC heater core so I would not be volunteering to replace one if I was not sure it was leaking.
Major PITA to swap an AC heater core so I would not be volunteering to replace one if I was not sure it was leaking.
Racer
Joined: Jan 2007
Posts: 334
Likes: 0
From: York PA
Testing the heater core in place - If you done have a compressed air supply but lots of air capacity in the ol' lungs you might try disconnecting the hoses from the block, plugging the end of one and blowing like hell in the other. Sounds kind of lame and bubba-ish but thats how I actually blow out the lines for my pool in the winter. Also dont inhale. Its poisonious.
chuck
chuck
Thread Starter
Heel & Toe
Joined: Jul 2008
Posts: 22
Likes: 0
From: Steamboat Springs CO
CJ 77 and Easy Mike...Yes, it is definitely anti-freeze leaking. I tryed tightening the hose clamps at the inlet/outlet for the heater core with no luck. You may be correct on the brazing failure on the copper sleeves. Will check once more (test drive) to make sure coolant is not on the passenger side floor.
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Thread Starter
Heel & Toe
Joined: Jul 2008
Posts: 22
Likes: 0
From: Steamboat Springs CO
Back from test drive & coolant leaking more heavily from evaporator box. Based on suggestions, will try a bypass or shutoff valve. I think its core replacement in the future!
