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Repeat failure of heater core
Posted to HVAC Forum on 10/17/2012 11 Replies


We have a problem vehicle we're trying to get taken care of and I'd like to see if anyone has any ideas or suggestions.

This car came in a few months back with a leaking heater core. We installed a new Delco heater core and sent them on their way. About 6 weeks later we got a call that they were out of state and had a floor full of coolant. The customer had someone bypass the heater and fill it up so they could drive it and we got it back in. When we pulled the core out, the small tube was broken clean off at the swivel fitting where it's crimped into the core tank. These are the ones GM ships flat in a box and you have to pivot the tubes to line up with the holes in the firewall when you install them.

We warrantied the part out and got them going again. Now, about 2 months later, they're back again with essentially the same thing. Floor full of coolant. I pulled the core again and found that the small tube is again fractured at the base of the swivel, although it hasn't completely separated this time. There seems to be no sign of contamination or corrosion in the system.

Anyone else seen this happen? Any suggestions?

Thanks for any help you might offer.

Mark Verdi Lead Tech US Automotive

Terry Hyden
Service Advisor
U.S. Automotive, Inc.
Springfield, Missouri, USA

11 Replies Received (View Replies)


car Vehicle Data

2004 Pontiac Grand Prix GT1 3.8L

Engine3.8 L
Trans4-speed Automatic (Electronic)