Heater core only stop leak?

[RMETeeJay]

I've got a faint smell through the vents, but nothing wet (yet). I would never use stop leak in my entire system because I know it would clog it up, but am wondering if it would be possible to run it through the heater core only. If it didn't work, I'd replace the core.

Has anyone attempted this before? I think I read somewhere before that it takes heat for the additives to work. I'm thinking of getting a drill operated pump or other small pump and bucket to: 1) flush and reverse flush the core with distilled water 2) refill the bucket with hot distilled water with the additive and pumping it through for however long it says in the directions.

Is this is crazy as it sounds in my own head? The only thing I'd be concerned about is messing up the 50/50 ratio. What is the capacity of the core?

 

[MountaineerTom]

It might work and hold off the problem for a while, or it might not and you’ve lost nothing but time and effort. And maybe a little money.

No idea of the heater core capacity. I don’t think it’s much though.

 

[astjp2]

Its an easy fix if it works, if not you are only out the $6 for the barsX

 

[RMETeeJay]

Thanks. I've never used the stuff. Should I be concerned about the residual additive coming loose after I hook everything back up? Maybe do a final flush after it cools down?

 

[astjp2]

I just hook things up, pour in your 50/50, top off with the stop leak and forget about it unless you get steam. But I am that way.

 

[Leinhit]

Seems if it really clogged up everything it wouldn't be on the market long.

I've heard this for years, anyone have first hand knowledge of glogging up systems?

Replacing the core is probably 5-6 hours it calls for?

 

[03coloradowrangler]

id avoid the stop leak and do the job right the first time.
but then again i have access to the tools to do it. which could be a major deciding factor for most people.

i wouldnt like to have to go through the whole cooling system in the future due to failure somewhere from a $8 can of stop leak. ive seen chunks of it floating in coolant in a buddys car that plugged his heater core up.. i could only imagine what the radiator looked like inside the cooling piping from left to right.

 

[Goatman]

There is stuff that looks like aluminum shavings(Stop Leak) and stuff that looks like gooey slop with rabbit pellets in it (Rislone?). Every time I used the ones that looked like aluminum shavings I've had problems with the radiator plugging and wanting to overheat. It works on bigger holes than most anything else. Plugged a hole from a .22 (don't ask. I'm sworn to silence). The other goopy stuff never seemed to actually dissolve in the coolant and wanted to just plug the radiator cap. There must be some different types out there that I haven't tried. The old regular Pepper is the only thing that has worked ok for me. Don't do the egg white thing! You'll never get it all out later. Sometimes it's just better to bite the bullet and do it right and replace the core. Put new hoses on while your at it. Those new silicone hoses are nice! Good luck which ever way you go.

 

[Jerry Bransford]

The heater core and radiator are totally connected together, you can't add that crap to just the heater core without it getting into the radiator too.

 

[John Scoggins]

Used BarsX for several leaky system back in the college days when me and my friends had no extra money. It has fixed leaky head gaskets, leaky radiators, and leaky heater cores, leaky freeze plugs etc. and have never had it plug up anything other than the leak.
GM uses pellets in some of their cooling systems from the factory, (AC Delco P/N 12378255) that apparently do not plug anything up.

Now, 20+ years after college I can afford to replace leaky parts so I would not use stop leak but I do keep a bottle in the vehicles when taking long offroad trips just in case.

 

[MountaineerTom]

I think the BarsX brand is what I used years and years ago in a Chevy Beretta. It was supposed to be a temporary fix. 150k later, it still had the same radiator in it when I sold it. Like @John Scoggins said, at that time I didn’t have much extra money floating around.

 

[RMETeeJay]

Thanks all. I am going to think on this a bit. This is a recent purchase. 109K with the original cooling system that I plan to completely replace. I'm beginning to think that the core should be considered part of that process.

I was hoping to buy myself a little time. I have AC, so I would also need to get that purged in order to replace the core. With colder weather and snow coming on in my neck of the woods, I'd prefer to keep my DD in the garage.

I may target the holiday season when I have a few days off from work to pull the TJ into the garage and do this right. Like many of us, I plan to explore very remote areas and I know that the peace of mind of a new system would be worth it to me in the long run.

 

[MountaineerTom]

You might want to consider changing the a/c evap core too while you’re in there. More money though, of course.

Here’s some info on changing the heater and evap core that may help you When the time comes.

https://wranglertjforum.com/threads/another-heater-core-replacement-and-a-c-evap-core.15568/

 

[RMETeeJay]

Are the evaporators a failure point historically speaking?

I appreciate the link. I've read both writeups on here as well as around the Web. It looks like some are able to leave the steering column in and rest the dash on the driver's seat to save some hassle?

 

[MountaineerTom]

Are the evaporators a failure point historically speaking?

I appreciate the link. I've read both writeups on here as well as around the Web. It looks like some are able to leave the steering column in and rest the dash on the driver's seat to save some hassle?

I don't really know. I figured it was the same age as the heater core and I know I would be kicking my own ass if it went out after not replacing it. LOL

 

[RMETeeJay]

No doubt, if I don't do it, Murphy will come to town.

Here's my plan: I picked up an OEM heater core. I am going to buy one of those AC charge kits that includes dye and the light for checking leaks and charge it up (I bought it with non-working AC). I'll then check all of the system except for the evaporator for leaks.

Then, I'll bring it to a shop to have it leak tested (to see if they find anything I don't) and evacuated and then when I have the HVAC box open, I'll check the evaporator with the light for leaks.

Does that plan make sense?

I know I'll need a set of quick-connect tools to disconnect the evap. Are there o-rings on those lines that I should replace? I would like to get the AC working again some day.

 

[TJ4Jim]

No doubt, if I don't do it, Murphy will come to town.

Here's my plan: I picked up an OEM heater core. I am going to buy one of those AC charge kits that includes dye and the light for checking leaks and charge it up (I bought it with non-working AC). I'll then check all of the system except for the evaporator for leaks.

Then, I'll bring it to a shop to have it leak tested (to see if they find anything I don't) and evacuated and then when I have the HVAC box open, I'll check the evaporator with the light for leaks.

Does that plan make sense?

I know I'll need a set of quick-connect tools to disconnect the evap. Are there o-rings on those lines that I should replace? I would like to get the AC working again some day.

You'll need a set of AC disconnect tools that usually come in a colored plastic set for like $10. The sell the green AC "O" rings in assorted sizes which are fine but you will also need the correct O ring lube (for ac "O" rings) for reassembly. Since the system is dead at this time do your testing to confirm status.

 

[T Crawford]

If you don’t need the heat just bypass the heater core

 

[Aviatortroy]

Having just done my heater core, I can say in all honesty it’s really pretty easy. Absolutely no need to remove steering wheel or even drop steering column. Several writeups on the internet on how to do it. My advice...

Drain coolant, disconnect battery and do everything under the hood first except the 6 nuts through the firewall ( 5 studs, but 2 nuts on lower stud right behind the back of the head)

Then do the interior. Remove centerconsole around shifter, kick panel below steering wheel,remove floor duct (3-8mm 2 on right side one on left) 3 torx on each side of dash, 2-15 mm nuts behind glovebox, 4 nuts across top. A couple electrical connections, and the main vacuum connector to HVAC box.

Cover steering wheel and column with a blanket to protect from scratching and use ratchet strap to lift dash up and back, hang from roll cage.

One vertical bolt holds HVAc box to the actual body under the dash, easy to miss.

Then go back under hood and remove the nuts from the studs through the firewall.

Slither the HVAC box out and remove the three hundred 8mm bolts holding it together. You may or maybe not have to finagle the vacuum solenoids to get it apart but that’s it.

Notes: I found several writeups none of which mention removing the center console but I found you cannot get the fooor duct out nor will there be room to get the HVAC box out with it in the way.

The clamp type line disconnects work way better than the collar type.

I did not replace my evap core.

 

[MountaineerTom]

One vertical bolt holds HVAc box to the actual body under the dash, easy to miss.

Ah yes, I put that screw back in place while I had the HVAC box out working on it. Wouldn't you know it, I forgot to remove it when putting the HVAC box back it. I had to loosen it all back up some to get the screw back out. LOL