Heater core leak
Thread Starter
Heel & Toe
Joined: Apr 2018
Posts: 16
Likes: 0
Heater core leak
ok so I had a leak coming from my heater box. I have replaced the heater core but I’m still getting a coolant leak coming from the heater box into the car.
Any suggerstons??
the only thing I can think of is maybe I got the hoses reversed but I put them on the same way I took them off.
need some help here.
Any suggerstons??
the only thing I can think of is maybe I got the hoses reversed but I put them on the same way I took them off.
need some help here.
Le Mans Master
Joined: Jan 2001
Posts: 9,247
Likes: 221
From: Dryden MI
One hose is 5/8, the other is 3/4. They also are pre formed with a almost 90 degree bend. The hose with the control valve is the supply. It is also easy to deform the tubes on the heater core if you tighten the hose clamp too tight. This is for an AC equipped C3, hoses are probably the same size though.
Last edited by Cooter Tech; Jun 9, 2018 at 08:55 PM.
Race Director
Joined: Oct 2000
Posts: 12,682
Likes: 3,135
From: Shamong, NJ
One hose is 5/8, the other is 3/4. They also are pre formed with a almost 90 degree bend. The hose with the control valve is the supply. It is also easy to deform the tubes on the heater core if you tighten the hose clamp too tight. This is for an AC equipped C3, hoses are probably the same size though.
All 68-82 Corvettes used 5/8" and 3/4" hoses, regardless of whether the car has AC. Because the hoses are different diameters, it's pretty hard to reverse them.
I doubt that it could be the hoses causing a leak inside the car. The heater hoses never come through the firewall, or into the interior. It's more likely that you got a bad core.
Melting Slicks
Joined: May 2009
Posts: 3,079
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Le Mans Master
Joined: Jan 2001
Posts: 9,247
Likes: 221
From: Dryden MI
The OP didn't tell us whether he has AC or not, but only AC cars use hoses with molded ends. Cars without AC, use a different core, and the hoses are routed differently, eliminating the need for the molded ends.
All 68-82 Corvettes used 5/8" and 3/4" hoses, regardless of whether the car has AC. Because the hoses are different diameters, it's pretty hard to reverse them.
I doubt that it could be the hoses causing a leak inside the car. The heater hoses never come through the firewall, or into the interior. It's more likely that you got a bad core.
All 68-82 Corvettes used 5/8" and 3/4" hoses, regardless of whether the car has AC. Because the hoses are different diameters, it's pretty hard to reverse them.
I doubt that it could be the hoses causing a leak inside the car. The heater hoses never come through the firewall, or into the interior. It's more likely that you got a bad core.