The Stovebolt Site Forums The Shop Area General Truck Talk Heater core

I posted a few weeks ago about my weak heater and replacing the 160 thermostat with a 180 version. Unfortunately, during the test drives, the gauge goes half way between the midpoint and the top end before settling down just over the mid mark (by this time I have the heater on full trying to help get the temp down). So I pulled the 180 thermostat and tested it; which showed it to be a 190 thermostat! I reinstalled the 160 deciding I could live with it here in Texas, but noticed that I now have a small leak from the core running into the cab. I guess the high heat/pressure might have opened something up (sorry this is such a long story). To finally get to my question, is there anything I can do to try to seal up the core? I ordered a new one online, but was told that it will not be here until mid january (maybe, he admitted that it is coming from China). Instead of waiting, what else can I try?

Thanks, Lee.

Oh, and it is the non deluxe version heater, just a recirc fan in the round core.

Well about the only thing i could think of would be to connect da heater hoses together temporarily. No heat, but no leak either.

Been there, done that.

Send it off to this guy and let him fix it up for you.

Bars Leak, Silver Solder, Blue Devil, etc. I've done a couple of "temporary" repairs with these products that ended up lasting the life of the vehicle.

Back in the day that I wrenched for a logging company, each re-cored radiator got a quart can of Bars Leaks. Otherwise they would be leaking again in a month or so. Rough roads, don't ya know. Don't put a whole quart in a pickup.

I did the circle hoses trick so I am still driving at least. I could not find where it was leaking when I took it out (it looked like it was coming from inside) but I did not put air in it to try to pin point the location. If I can find the leak I will try my hand at soldering and see if I can fix it.

Lee.

I had poor luck with having the heater core repaired by a local radiator shop. It didn't leak until the water got up to temperature and then started a small leak. Did this 2 times. Finally purchased a replacement core from Brassworks. I posted about it here https://www.stovebolt.com/ubbthread...rks_Recirculating_Heate.html#Post1011395

I may have the same issues about it only leaking when hot. I just pumped it up to about 20 psi (in a tub of H2O) and it did not leak. I am going to reinstall it and see if the leak returns.

Lee.

Chuck,
I just read your post on the Brassworks core; really nice! I’ll look into that if my original is still leaking.

Lee.

I also did a brassworks in my 49 gmc with my LS swap and I give it 2 thumbs up 👍 👍. Mine fit great and work great. Mine runs at a constant 190-195 so its nice and toasty in there. Fan is “loud” on high but i keep it on medium and it heats perfect for me.

I also went the brassworks route on my 55.2 3100.

LeeD Well you might try the oldest trick in the book...a tablespoon of black pepper in the radiator LOL !Seriously that will work, however I hate to put dirt in the cooling system !!

Tricks like that are just a temporary “get ya home” fix. Its not something that a critical thinker would ever trust long term.

It looks like I will need to replace the core. Driving to work yesterday I had not gone a mile when I looked to the floor and saw water already starting to pool up. Fortunately I have shut off valves on both hoses so I closed them both and stopped the leak. Unless the leak is at the connections, it looks like leak is worse. Oh, well.