I don't know if it's just my rotten luck or if there's a problem with these things, but I've had three heaters go bad and leak in some five combined years of driving thirdgens.

I don't want to have to do this job again only to have another heater give up the ghost two years later. Anyone have a recommendation for the best damn heater core you can get?

 

Had the same problem. Seems with the bypass valve, during the summer the coolant sits and corrodes the core. Winter comes and leaks. Replaced 2 in 1 year before bypassing the diverter valve and just having coolant run thru the core all the time. Been 4 years since and no leaks.

 

I am in the cooling business, stock, sell and repair/build/rebuild this stuff. The overall quality of all these parts from radiators to heater cores to almost everything has gone down hill dramatically over the last 3 decades for sure. Problem with brand shopping is you never know what's in the box regardless of the sticker. Is your heater an aluminum replacement or an original brass piece? I know when we sell brass heaters, policy is to examine the piece before selling or installing & look for solder shortages around the tubes and at the corners of the tanks where they are soldered to the core. If problems are found, we touch them up with solder & retest them before installing or selling. Brass heaters are almost extinct now so if aluminum, little harder to see defects. Another problem could be electrolysis which can eat up a heater or radiator in a hurry. If you suspect that, there are several articles out there on this problem, how to check for and correct it. ( can be a pain in the a@@ to find the actual problem sometimes ). Although this is not a common problem on these older cars, if it is present, it will eat up aluminum pieces much faster than it will brass for sure. All that being said, we all occasionally fall victim to the high demand for cheap parts so more than likely, that is the problem. As for your question, I would try to find a new brass heater and then take it to a radiator shop if you have one in your area. If they are reasonable folks, it should not cost too much for them inspect it, add solder if needed and then retest it. At one time radiator shops were easy to find but unfortunately there are few left as most did not reinvest in their business and stay educated and progressive in their industry. On the up side, most of the ones that are left would hopefully have their poop in one boot and be able to help you out. Good luck.

 

All of mine have been brass. Guess I'll start looking into correcting electrolysis and shopping for a new brass one.

Thanks for the help.

 

If they have all been brass, than you may be falling victim to the mass produced, I don't give a damn, solder work. Where are they failing, around the tube/tank joints, where tank solders onto the corners or out in the middle of the core?? If in the middle of the core on all, check for electrolysis, if hose connection/tank solder cracking or tank to core seam leaking, take new one to radiator shop and have them test and touch up any solder that seems short or lacking, then retest & install.