The Stovebolt Site Forums The Shop Area Engine Shop 58 3100 no heat - heater core or valve?

Want to get this tackled this year. Am NOT a mechanic but I am here to learn. Have the deluxe heater with defrost 235 straight 6. Every once & a while she spits out a bit of rad fluid in the cab under the heater box. Does that mean it's my heater core for sure? Or could it just be the valve & if so how do I test that? Thanks as always....

take it out and take it all apart. The valve and heater core are both in there along with a 90 degree elbow (rubber heater hose). Any one of them can and will leak! I took my core/valve assembly out of the box and then hooked it up to the engine outside the vehicle (heater hoses are long enough to do this) and started the engine up to see what was leaking! Your valve could be stuck closed or your core could be plugged up as well. Either way, you have to take it all out to test and then fix.

Thanks! That sounds like something I could do. That's what I love & fear about my truck, the tech is/seems simple but I have zero prior knowledge. I plan on learning as I go so this forum is a blessing.

also be careful with the core as they are not available anymore. Well, let me re-phrase that, there is someone making them, they want 300$ for one though!

I was told there is a place in town that can rebuild it if necessary (and salvageable).

the issue is finding a new core to solder to the existing tanks if needed. The shop that repaired my last one (59 Suburban) told me a couple weeks ago that he can no longer get the proper thickness core for these unless he buys a whole block of it (200$). Not to say that he knows everything but, he has been doing these old rigs for years. If you find a local shop that can replace the core for you, please let me know!

Is the thermostat working OK?

I'd be lying if I said I knew if the thermostat was working ok, the gauge is iffy at best (maybe that's why?). I've read that to test if it works you dump it in boiling water & see if it opens up? (not sure what that would look like).

you can watch the thermostat open if you put it in a pan of water and bring it up to a boil. Here is a link that shows an open and a closed thermostat.
http://www.agcoauto.com/content/news/p2_articleid/191

If the engine is hot but the hoses are cold the t-stat is bad.

My heater never worked very good, and neither did the temp gauge. I thought that was par for the coarse for an old truck. But then one day I replaced the thermostat as part of a pre-road trip prep and the heater suddenly started putting out some real heat. So much, in fact, that I now roll my window down a bit when the outside temp gets up around 30°F.

It is almost always a good idea to replace the t'stat., can use a 180 or so to let engine run at efficient range, burn off moisture from engine, especially if used for short trips.

Ed

There is a radiator shop here in Knoxville that replaces old heater cores. They replaced my standard heater core in my 59 for 65 bucks if I remember right.

I had my old heater re-cored a little over a year ago. It's been working like a champ since.
Work done by Camp Springs Radiator Service, Inc. 6416 Aaron Lane Camp Springs, MD 301-868-5757
It was $210 for the work.