Yeah, definitely. Could be your problem. Wouldn't that be easy??

For the short term you could just get a length of heater hose universal heater hose and make a "U" further upstream where the metal heater pipes are (pipe them together with the hose) ...and by pass the heater core entirely for now ...temporarily. You won't have any heat, but the purpose is to test the HC. Spray off the underside and wherever there was anti-freeze with a water hose & shop vac it clean ....drive it around a bit for a couple days. Check things. If you still see leaking anti-freeze under the vehicle, it could be the metal heater pipes (where the heater hoses hook up -- if your rig has them). Or maybe even a bad water pump or something (check underneath ....the weep hole under the water pump nose). But if you bypass the heater core and you have leaks then you know it isn't the heater core. Just a thought.

It's also possible there are is a leak up by the engine AND the H/C... Good luck

 

Yeah she doesn’t drive yet thought that’s the problem. 🤣 7K in and she still doesn’t drive.

I’m assuming it’s this left hose. You can see where it’s been wet. I uploaded a picture and it’s not showing for some reason.

 

That's definitely your problem. Those two hoses are going back to the cabin to the heater. I would swap them both. I had a leak from them too.

 

I’m hoping that’s “definitely” my problem haha. It’s hard to see in the picture but the hoses have been wet. We will see. I will replace them. I need to drain the coolant and pressure test the rad too.

 

Did your leak get inside the cabin into the floorboards when those hoses leaked?

 

You might also back-flush the heater core with a garden hose (run water the reverse direction of coolant flow). You'd be surprised the crap that can come out of a heater core. I don't know the direction of flow off-hand w/o looking. But you could look that up, or maybe someone here has done it recently.

 

Can’t I just do it both ways? It shouldn’t matter. One way will be the correct way and one way will be a back flush, I don’t think either should harm it should it ?

 

Sure you *could* ....but the idea is to dislodge crap that is in there. Blow it out the way it came in. Usually most is on the inlet side and settles down ...gets caught or covers some of the tiny passages on the inlet side of the H/C. If debris could go through the heater core, it wouldn't be caught or built-up inside there. So if you begin by pressurizing the inlet side you essentially force crap into the tiny passages it was to big to go through in the first place (harder) with high-pressure water (potentially making blockage worse). A lot of debris also settles on the bottom. Most guys first do a reverse-flush or two. Then do as you say and go both directions. There's a bunch of videos how to backflush a H/C.

It's optional. You don't have to do it. Just one of those things that's good to do on an older vehicle. I've had heater cores which heated a lot better after a flush. And then some weren't that gunked up much, and didn't make much difference. If your heater core turns out to be the leaking culprit in the end, then you'll be replacing it anyway ...and a flush is irrelavent.

 

all good points. I’ll figure out which was is the proper way. I’m assuming from the thermostat is the regular flow and back into the system, and not the other way around. I don’t think it should go through the core before it passes through the thermostat right?

 

No, mine was just outside - hose was kind of brittle and at some point clamp cut to it, so coolant was leaking, but it didn't make it to the cabin. But i had back of the engine "nicely" marked with it...