more detailed instructions on heater core replacement?

[Need For Steve]

Hey guys, so I'm planning on replacing my busted heater core soon, so I went out today to dig under the dash to get a feel for things and I'm a bit puzzled to say the least.

I've done a bunch of searching here and on other pages, and found a lot of rather inspecific "take the glovebox out, remove the black thing and there's the core!" posts, but nothing step-by-step or a detailed write-up. After removing my glovebox and hush panel and looking around for about 30 minutes, I still can't relate what I'm seeing to the pictures I've come across showing what needs to come off or how it comes off.

Does anyone know of a step-by-step, or at least really detailed, write-up on how to get to, remove, and replace the heater core?

[1oldman]

The instructions, if there are any, will depend on you having a manual A/C - heater or ECC (Electronic Climate Control). Which do you have? - BC

by the way, before I forget, ground your new heater core just in case there is any stray electrical voltage any where in the car. That can cause a premature failure of your core. - BC

[Need For Steve]

I have ECC. I've read also about grounding the core, I'm assuming I can just run a bit of insulated wire from somewhere on the core to a screw on the chassis?

[1oldman]

I have ECC. I've read also about grounding the core, I'm assuming I can just run a bit of insulated wire from somewhere on the core to a screw on the chassis?

Correct. That is what my son did for me. I am posting two threads that should be of help. I can tell you that my son and the dealer both removed the dash to replace the heater core in my old Bonneville. IIRC willwren replaced his without having to do so. He laid the driver and passenger seat backs all the way down flat, layed down flat on his back with his head on the front passenger floorboard, looking up under the dash. He had to do everything by feel.

Here are the two posts that I hope give you the information you are looking for:

heating core replacement
http://www.pontiacbonnevilleclub.com/fo ... eater+core

How to change Heater Core
http://www.pontiacbonnevilleclub.com/fo ... c1516.html

Let us know how it goes. - BC

[Sirius]

When you get your heater core cover off, take the time to pull the airmix actuator off, take it apart, and inspect the gear for cracks. If it's cracked at all, replace the actuator now and save yourself lots of future pain. There is a little blurb on removing the heater core cover in this article too:
http://trialsnuts.com/ecc.pdf

[Need For Steve]

Thanks for those links folks, I'm gonna dive into this today and see about getting it done...

[Need For Steve]

Ok, I can't figure out for the life of me how the vac fitting comes off the box beside the core cover. I know that box has to move to give room for the heater core cover to come off but I just can't figure out how...

Anybody?

[gmman]

best i remember, 10mm nut in the center of the vac line assy. once nut removed, take thin flat blade screw driver and pry around entire periphery small amount at the time gradually loosening the vac line connector. you will probably destroy vac line nipples in the process (not unusual). there is a fix for that in forum.

[Need For Steve]

Got it! Thanks for the advice and links. The vac stuff wound up breaking, so I've got no dash vents for the moment, but since my ECC wont channel heat to the dash anyway it's not a big issue.

Thanks again, folks!