Leaking Heater Core?

[ArdWrknTrk]

Just to be clear: if my [A/C equipped] heater core were truly leaking, there should be coolant leaking *inside* the cab on the passenger's side.

Right?

I just checked the box from the inside again, and it is not wet with coolant - at all.

Am I barking up the wrong tree?

 

 

Not only should the box have coolant in it, the windshield should be covered in glycol slime.

You'd likely see steam (even in the desert) but you can't miss the vape film.

[1986F150Six]

Not only should the box have coolant in it, the windshield should be covered in glycol slime.

You'd likely see steam (even in the desert) but you can't miss the vape film.

Lariat 85, try wrapping each individual hose, as it exits the heater core, with paper towels. Go out as far as you can toward the plastic fender liner. Drive the truck and then check the hoses. One side will have evidence of the leak and possibly the location.

[LARIAT 85]

Lariat 85, try wrapping each individual hose, as it exits the heater core, with paper towels. Go out as far as you can toward the plastic fender liner. Drive the truck and then check the hoses. One side will have evidence of the leak and possibly the location.

I tried your idea, and found the culprit. It turned out to be a loose clamp on one of the heater hoses. I tightened it back up, and the leak has stopped.

Thanks for the advice!

[85lebaront2]

Lariat 85, try wrapping each individual hose, as it exits the heater core, with paper towels. Go out as far as you can toward the plastic fender liner. Drive the truck and then check the hoses. One side will have evidence of the leak and possibly the location.

I tried your idea, and found the culprit. It turned out to be a loose clamp on one of the heater hoses. I tightened it back up, and the leak has stopped.

Thanks for the advice!

I started salvaging the flat spring clamps in junkyards, they may be a royal PITA to R&R, but they don't loosen with the heating and cooling cycles.

[grumpin]

I started salvaging the flat spring clamps in junkyards, they may be a royal PITA to R&R, but they don't loosen with the heating and cooling cycles.

Glad you found it!

Bill, I have replaced a lot of those clamps, but kept them. Always hoping to find a good tool for them.

Any suggestions?

[FuzzFace2]

Glad you found it!

Bill, I have replaced a lot of those clamps, but kept them. Always hoping to find a good tool for them.

Any suggestions?

There is a slip joint plier type tool just for them clamps.

They have little indents for the clamp ends to fit in and not slip out.

https://www.geniustoolsusa.com/550810.html?gclid=EAIaIQobChMI-YDG89q85gIVAtbACh2IBwMaEAQYDiABEgJRfPD_BwE

Google will post up a bunch of others - "hose clamp pliers"

Dave ----

[85lebaront2]

Glad you found it!

Bill, I have replaced a lot of those clamps, but kept them. Always hoping to find a good tool for them.

Any suggestions?

I have an entire kit of strange pliers I bought years ago, label on the case they are in has come off, I don't think they were Harbor Freight. I will try to get a picture of them. There is a pair specifically for separating the hose from the fitting too.

[grumpin]

I have an entire kit of strange pliers I bought years ago, label on the case they are in has come off, I don't think they were Harbor Freight. I will try to get a picture of them. There is a pair specifically for separating the hose from the fitting too.

Thanks guys, Dave I think I have a pair of those.

The flat square type is what I have more of.

I’ve used 90° needle nose with success, if there is room.