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Heater Core Replacement

idrivejunk said:
Mmm steak.
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you mean like this

crockpot-coca-cola-peach-barbecue-p.jpg
 


Has anyone seen a walk through or video of the short-cut method to replacing the heater core? I have searched everywhere and can not find one.

Thanks,

Mike
 
mikedpp said:
Has anyone seen a walk through or video of the short-cut method to replacing the heater core? I have searched everywhere and can not find one.

Thanks,

Mike
Click to expand...

Not sure if there is a short cut. It's pretty straightforward as is, remove center console, covers and seats (not necessary, but gives a ton more room to work) to gain access to heater core. Install new heater core, reinstall all the other crap and you're done. It's not hard, just awkward and frustrating because you're working off your back at odd angles.
 
So is the center console in the way of reaching some of the screws or plastic rivets, so you absolutely have to take it out? or is this just a continence removal for maneuvering around?

Also, do I need to pre-drill those #6 or #8 sheet metal screws or will they self-tap and not crack the plastic?
 
You definitely need to take out the center shift console. It's four bolts and then you disconnect one wiring harness.

The seats are optional (I didn't take mine out but I did get into some rather interesting poses/positions)

Jeff
 
Wow...took those 2 covers off, that was some awkward work w/ the Air diverter and the core cover (idk what they're called). I found a drill and rotary tool were the best at removing those plastic donuts. I AM grateful for not having to remove the entire dash (like other cars), but seriously GM...use screws instead - think about the end user.

I need a new foam seal for in front of the heater core, mine's all wet a messed up. Did you guys just use weatherstrip from HDepot, cuz I can't find a "Heater Core seal" or "heater core gasket" at a parts store. I'm just worried about the temperature of that thing against the generic household weatherstripping.
 


My replacement AC Delco heater core came with the foam gasket.

When I put mine back together I only re-installed the (inner) core cover because I wanted more
heat on my feet rather than under my seats (no one sits in the back and my car was nearing it's
life expectancy)

Jeff
 
I installed an Adv'd Auto HC (PN 399329), it looked identical. Ended up using 3/8" weather seal from Lowes. A guy in a GM forum said he tested it in an oven at 350 and it was fine (see link).

Finished this project couple days ago. Not the hardest thing I've done, but definitely the most inconvenient. I think the plastic donuts were by far the worst for me. I also spent a lot of time trying to get the heater hose clamps off the HC near the firewall - they were just in and awkward spot with the pliers. Replaced the heater hoses as well, cuz why not, and I used standard hose clamps to reattach to the HC and tensioner fittings. Two flushes with distilled H2O (in order to remove bars leaks I had to use to get home 200 miles), refill, burp, and reassemble.

I didn't reuse the little screws I took out. I just used the 3/4" #6 sheet metal screws for the whole reattachment. I think spazzz referenced these earlier in the thread. They went in fine, no pre-drilling. I did use a drill with a right angle attachment to take some labor out of it.

I'm glad this thread existed, because it truly did help me out, there's not videos on GP's - so thank you to everyone.

http://www.gmforum.com/general-gm-c...-replace-gms-oem-heater-core-seal-kit-308307/

This also visually helped me a little bit before I got started - https://www.youtube.com/watch?v=_cOYV_dy47A
 
In the future, there is a spring hose clamp removal tool. Should be part of Adv'd Auto Loan-A-Tool dealio..... One end kinda looks like a bicycle hand brake w/cable going down to a small "caliper" looking end.
 
Does anyone have photos of the heater core cover and the HVAC cover in place? I've got everything replaced but I may have offset the covers, I'm not sure. It doesn't look correct. I'd only use the heater core cover but that seems to severely limit the amount of heat thrown on the windshield or through the dash vents.

Good floor heat but only cold air through the dash and defrost. Is my problem something else?
 


PizzaAndDoughnuts said:
Does anyone have photos of the heater core cover and the HVAC cover in place? I've got everything replaced but I may have offset the covers, I'm not sure. It doesn't look correct. I'd only use the heater core cover but that seems to severely limit the amount of heat thrown on the windshield or through the dash vents.

Good floor heat but only cold air through the dash and defrost. Is my problem something else?
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^^ likely the blend door. Just finished installing a heater core into my 2000 GTP. I have a pic of the heater core cover. Not sure GP you have though.


20161022_145951_zpsvr3ralnv.jpg


20161022_145957_zpsiagvhzzn.jpg
 
CHI2000GTP said:
^^ likely the blend door. Just finished installing a heater core into my 2000 GTP. I have a pic of the heater core cover. Not sure GP you have though.
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HINT: This thread is in the 2004+ specifics part of the forum. Your cover(s) look a lot different.

Jeff
 
Thanks for the post.... looks like this has been up for quite a while.... it also looks like the pictures are now gone from the instructions. Do you still have those?
 
If I remember correctly this link has the same pics/diagrams from the GM manual.

http://www.justanswer.com/pontiac/5mfzm-pontiac-grandprix-supercharged-replace-heatercore.html

It's nice to have the locations of the screws which these point to. Depending on your physical size, you might be able to get at the core from both driver and passenger footwells without removing anything else.

About the hardest part is sneaking the cowl out of the underseat duct work run, right below the radio.

The 2 hose clamps inside the engine bay gave me a struggle, or than that not bad.
 
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spazzz said:
If I remember correctly this link has the same pics/diagrams from the GM manual.

http://www.justanswer.com/pontiac/5mfzm-pontiac-grandprix-supercharged-replace-heatercore.html

It's nice to have the locations of the screws which these point to. Depending on your physical size, you might be able to get at the core from both driver and passenger footwells without removing anything else.

About the hardest part is sneaking the cowl out of the underseat duct work run, right below the radio.

The 2 hose clamps inside the engine bay gave me a struggle, or than that not bad.
Click to expand...
Thanks. I appreciate the help.

Sent from my XT1254 using Tapatalk
 
IIRC, the evap coil is buried behind the dash, so most likely you will have to pull the dash and a bunch of other stuff to get to it. Are you thinking you have a leak in it? Have you had the system dye tested? Just trying to save you some headache.
 
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