76 heater core replacement
 

I'm getting ready to replace the heater core in my 76. I bought a core on e-bay advertised as "NOS" because of all the threads I've read about improper fit and leaks on after-market cores. The core I received was made by US AUTO RADIATOR made on 6/86 and labled 3015145, which I believe is the correct part number. Does anyone know if they were ever a supplier to GM and should it be a good fit?
Thanks for your input!

That's a good Q and I cannot answer it directly unfortunately ...

These things are readily available though, and if you can get the old one out you will have no problems. At first glance your message looks as if you're looking for NCRS replacement though. Is that true, or are you just trying to reassure yourself of a fit? If the latter then don't worry because as I suggested these are easy to get.

The problem is the replacement labor! I pulled mine outta my '76 when I did the dash. I had all the ducts out, and pulled the heater box out (WOW -at length!) to put a new core in it. By the time I had done all of the resealing of the A/C ducting systems and the heater box was out, I was fried.

I spent about an hour trying to get the heater box open (on my workbench) to put the new core in it, and gave up. I wound up putting the box back in, with the old core in it because I couldn't get it open!

Lucky for me, it wasn't leaking with the old motor in the car .... and since putting the 383 in her, I have never connected the heater.

I was hoping for NCRS but not that big a deal. I'm also replacing evaporator and vir which I have purchased and are NCRS. Evaporator has hole worn in it caused by the heater hose clamp. Gm isssued a service bulletin on this in Nov/76 and unfortunately-I got bit. I don't know how to insert a link to this bulletin but any other 76owners-don't let this happen to you. PM me and I will send you the link. Also has picture on bulletin showing you how to fix problem!