I had a leak in my truck ('86 GMC 305 V8) heater core a couple (or 3 or 5 ...) of years back and instead of trying to repair it I just bought a replacement from NAPA - cheap because my son works there (his employee discount , nothing shady) . Cheap looking aluminum unit , but it lasted a couple of years . The next one lasted less than 6 months ... and the next 3 or 4 each lasted about a month . All properly installed , system flush the first couple of times , but antifreeze ain't free . The last one that failed is still in the heater box , though the hose is now routed from the engine straight into the radiator because it started leaking while I was halfway home (halfway between Memphis and Mtn View) . So now fall is coming on , winter will be here soon , and I'm not particularly inclined to put another "lifetime warranted" NAPA unit in . So what the hall , I still have the original , and it's out in the shop in a box . Let's see where it's leaking ... and it turns out the leak is in a place that's easy to get at to clean and resolder . Cleaned , soldered , and I just pressure tested it to 25 psi , which is a good bit higher than system pressure . I love it when something works out this well ! Now I need to pull the radiator , it started leaking a few weeks ago - and this one is going to be harder . Aluminum core with plastic tanks , and the water stain is right in the center of the core . I need to see if it's a surface tube or deep inside . Either way , there is really only one way to stop the leak , and that's to cut/crimp the leaky tube . Shoot a wad of sillycone in there before I crimp . If I had more experience I might try to TIG it , but those tubes are a lot thinner than I can currently manage to weld without blowing holes . Then there's the tick that started a few days ago ... High likelihood it's the fuel pump pushrod . Not sure yet if it's the pump failing or the cam lobe , but it's also gotta be fixed before the snow flies . -- Snag Shade Tree Mechanic and Metalworking Hack .
9 years ago