Heater Core - 10/09/2013

What's the one job you should always do but no one wants to do? That's right, the heater core! If you don't take advantage of having the car apart, you'll always regret it. Kind of like I did after going for a drive to get stereo parts one day. I wound up driving a swimming pool home.

Yeah, it makes a mess. Fortunately no carpet to ruin.

It even made it all the way to the back seat area. Once again, no carpet to ruin.

I'm old hat at this. Drain, remove, replace, fill! Sounds easier than it is... But it beats doing this on an F-body!

Hoses are removed.

And since I've documented this so well, it's obvious what happens next. Remove 4 speed nuts from firewall, remove AC ductwork, disconnect 3 vacuum hoses, remove 2 sheet metal screws, pull box out. And this is what you have! It's obvious this car spent some time with water getting inside and surface rusting everything. This is why removing the AC box from the engine compartment side is bad! Water and moisture now have an easy path in.

Old heater core. It still had a GM part number inked on the back. And was obviously leaking.

New heater core! I hate how these tubes are not the same as the old ones. Means I have to bend ever so slightly, then verify no leaks BEFORE installing. Manufacturers insist that the aluminum they make them out of is superior to the brass and copper of the originals. I'm thinking it's just cheaper and they are telling us that to make themselves feel better.

Hole in the firewall. Half of the firewall insulation is ripped and missing, so add that to the list of things to do "one day."

All mounted. The 2 short sheet metal screws that mount the brackets down come awfully close to the core, but they don't touch. I was nervous. I was also nervous bending the tubes as well, the entire structure moves when you do that, but no leaks on the bench afterwards.

And all back together. Sure, I didn't make it look pretty but it functions nicely!

And DONE. Ran it for 25m up to operating temperature with the cap on, no drips or leaks and plenty of hot air when needed. Win!

Shop rate for this job is around 6 hours, which isn't completely unrealistic. I probably spent about 4.5 hours on it, but I'm leaving the AC and glove box out because I want to install my new 4x10 speaker in the front and that requires the dash be pulled to do so. Perfect opportunity to finish the stereo now!

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Last updated October 9th, 2013