[goatman65]

My core had a 'now and then' leak. Sometimes it would drip on the floor sometimes not. I now have it out. Is there a way to check it for a leak out of the car? Isn't there a way of using air? I suspect it is leaking at one of the tubes for the hoses.
Also, what does the blower resistor do that is mounted on top the case? Non a/c.

[Pepi]

Hook up a hose to one end and plug other end with thumb and turn on water. You'll see the leak. The blower resistor is for the different fan speeds.

[66Post]

You can plug one end off and hook up an air line with no more than 5-10 psi to it dunk it in a bucket of water and see where the leak is. Years ago I would solder them to fix, these days I would just replace it.

[HWYSTR455]

If you have it out of the car and it's old, replace it and be done with it. Wash the box out real good and buy a seal kit too while you're at it. Make sure you use the correct size hoses for each fitting too. I've seen where they leak at the hose end because someone tried to clamp the wrong size hose down.

I've also coated the hose nipples with antisieze before assembly to aid in removal down the road, keeps the hose from 'sticking' to the nipple. Just need to make sure you appropriately tighten the clamp.

Don't apply pressure to the hose nipples/ends during assemby/tightening, like sideways, or you can damage the core where the nipples are soldered to the tanks.

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