Heater core removal?

[jaymizzel29]

Anyone know how to take the heater core out? Mine has gone past the point of no return

[centralcoaster33]

You can pull the dash, get to the climate control stuff, pull off the larger box type cases and expose the heater core. You'll disconnect the two pipes at the firewall from the engine bay side. You'll then pull the heater core out into the interior. Plug your firewall holes with something, anything, don't leave them open. Connect the two heater core hoses to each other probably with a single hose. You can delete the in-hose valve if your car uses one to control heat. Put all else back together. Purge your radiator of air bubbles ("burping the coolant") and you should have successfully bypassed the heater core.

I suggest repairing it or replacing it. Having a working heater and functional defrost (for like driving in the rain and on cold mornings and nights) are important features for a daily driver. Even races cars (example: the SCCA improved touring groups) aren't allowed to remove their defrost/ heater setups. It's for function and safety. Removal of AC is allowed. AC is a luxury.

You can do it with the FSM or just get some tools and work your way through my summary.

All FSM chapters:
http://www.nicoclub.com/FSM/300zx/1986/
Heater Chapter:
http://www.nicoclub.com/service-manual? ... zx/1986/ha

[centralcoaster33]

BTW - I thought mine was toast, but it was just jam packed full of orange stuff and chunks. I got a garden hose, connected it to one end of the heater core at the firewall, disconnected the other hose at the firewall, and blasted all the stuff out of the other end. This helped get more heat. If your's isn't leaking coolant down into the cabin, you probably just have a clogged one. I do wish I had even more heat, but I have a giant radiator and it never really gets hot.

[jaymizzel29]

Thanks a lot man, mine is leaking into the cabin and smoking lol. I have a new one coming just didn't know how to get to the old one. Thanks a lot

[centralcoaster33]

Oh, I see. I'm not sure why I assumed you were removing it without replacing it. Silly me! You may have to open up more of your interior to access the firewall filling fluff and stuff. I figure you'll have a mess of coolant stank and maybe even some rust to deal with. So, you'll be pulling back your carpet and such to clean it up while in there. Best of luck and be sure to add any further questions you may have regarding access/ removal.

[jaymizzel29]

I'm having trouble getting the white box that holds the heater core out of the car. Any advice?

[jaymizzel29]

I'm having trouble getting the white box that holds the heater core out. Anyone done this before have any directions/pictures anything will help thanks

[centralcoaster33]

Well, I don't have the same car, but you often have to remove the other parts to get to the box for the heater core. I mean the blower assembly and the mixing box often come out first because the seams overlap. The heater core box would have some bolts to the chassis, maybe 4 or 5 to remove. The top ones are tough if you haven't taken the dash out of the way. Then theres the two coolant pipes that need to be detached from the core to pull it out. Have you pulled the dash, blower and mixer chambers? Have you disconnected the wires and the mixer door controls?

[jaymizzel29]

I've pulled the dash out and took the bolts off the heater core box I haven't disconnected the coolant hoses yet though that's probably why it won't come out

[centralcoaster33]

Yeah, those would hold it to the firewall I'd think. Here's a couple links to similar threads. Sounds like your into a lot of "fun" for a few hours. Someone even says remove the steering column. Ugh!

advice-on-replacing-heater-core-t463367.html
has-anyone-changed-the-heater-core-t476209.html

[evildky]

IIRC there was a bolt that comes through the firewall from the engine side that also holds the core in.

[evildky]

http://xenonzcar.com/z31/heatercorereplacment.html

[jaymizzel29]

Thanks for all your help couldn't of got this far without yah