HOW TO TEST HEATER CORE FOR LEAKS???

[Killer50stang]

I have coolant running onto my passenger side floor. I pulled the heater core but can't seem to find any hole. Is there a better way of testing this?

Jason

 

[trbkrb]

I saw one guy that clamped an old bicycle tube onto the outlets and filled the core with air while it was under water. He tested his new one after installing a prior new one that was bad. Any hole, and the air would bubble right out.

But most likely, 99% of the time, if you have coolant inside the car, it is the core. That is the only place coolant circulates besides under the hood.

 

[Aryan15]

I would replace it and get the new one pressure tested at a radiator shop.

 

[Roland69]

use a flow restrictor with the new one in the inlet side

 

[AnthonyR23]

can't you just fill it with water and see if it leaks??

 

[TRWXXA]

can't you just fill it with water and see if it leaks??

Nope. Most leaks are small, and water will only come out when it is under pressure.

I like the bicycle inner tube idea.