Leaky Coolant at Heater Host to Heater Core

[2KJimmySLS]

I just replaced the heater core this past weekend. Feeling pretty triumphant from that minor victory I was hoping my troubles were past. Not so.

I have a 2000 GMC Jimmy 2dr 4wd, v6, etc, with 130k miles. Anyway, I've been smelling coolant for the past couple of days but had no idea where it was coming from. Thought it was left over from the heater core job. Found out this morning after pulling into work and seeing smoke pouring from the back of my hood that I appear to have developed a leak at the 3/4" hose at the heater core. Coolant is coming out from the end of the hose and I'm wondering what could cause that.

The clamp seems to be plenty tight. Could the hose be bad somehow? Could I have overtightened a clamp and warped the connection and does that mean I'm screwed and have to replace this heater core?

Anything simple that I'm missing here?

[MT-2500]

Originally Posted by 2KJimmySLS

I just replaced the heater core this past weekend. Feeling pretty triumphant from that minor victory I was hoping my troubles were past. Not so.

I have a 2000 GMC Jimmy 2dr 4wd, v6, etc, with 130k miles. Anyway, I've been smelling coolant for the past couple of days but had no idea where it was coming from. Thought it was left over from the heater core job. Found out this morning after pulling into work and seeing smoke pouring from the back of my hood that I appear to have developed a leak at the 3/4" hose at the heater core. Coolant is coming out from the end of the hose and I'm wondering what could cause that.

The clamp seems to be plenty tight. Could the hose be bad somehow? Could I have overtightened a clamp and warped the connection and does that mean I'm screwed and have to replace this heater core?

Anything simple that I'm missing here?

Pull hose off look for a crack or hole in it and if it looks good slide it back on and reclamp

[Airjer_]

You'll have to take the hose off and see if the core pipe is distorted. If not than maybe you just need a new hose?