Remove the heaterbox without touching the fender or tub?

cdnpont · Canadian Poncho Superstar!

Remove the heaterbox without touching the fender or tub?

JC2+2 · Poncho Master!

I removed the one in my '68 using a long 1/4 drive extension with a swivel.

But I'm pretty sure there's an old post on this subject here somewhere.

-- Edited by JC2+2 on Tuesday 20th of November 2018 01:40:56 AM

Pontiacanada · A Poncho Legend!

JC2+2 wrote:
But I'm pretty sure there's an old post on this subject here somewhere.

Yes there are.

Two words ... small hands. blankstare

68 Grande · Guru

I left the fender in place but took out the inner wheel well tub but it was a pain no doubt about it. Upon replacing the inner tub I had to replace all the fasteners as they all broke off due to corrosion. Here is a few pics. I had the motor out as well. You can see that the firewall was the original color then sprayed black in a resto.

heater box 2.JPG

heater box.JPG

heater box 3.JPG

-- Edited by 68 Grande on Tuesday 20th of November 2018 09:15:30 AM

-- Edited by 68 Grande on Tuesday 20th of November 2018 09:31:53 AM

seventy2plus2 · Canadian Poncho Superstar!

There is 1 stud attached to the heater box extending through the firewall whose speednut is impossible to get at. You can drill the rear of that stud out from the passenger compartment side of the firewall.

I used this trick when replacing the heater core of the 454 Laurentian.

oshawacliff · Poncho Master!

Mark
Here is the manual diagram of the heater box inside the car with part numbers.

Photos of the box available if necessary.

Are you doing this in the driveway/carport or do you have a warmer location.

Heater box .jpg

68 Grande · Guru

The far left two fasteners and the most difficult to access are "screws" (#11) and not speed nuts. Cliff`s diagram shows that and that is the way my 68 was as well. Big PIA accessing those screws.

cdnpont · Canadian Poncho Superstar!

Thanks for all the reply's and pics guys. I think I'll seriously consider drilling out the inaccessible stud from in car.

When I reassemble, I might not even replace it. A good bead of sealer probably would be fine. And yes Cliff, nowhere warm to work. cry

seventy2plus2 · Canadian Poncho Superstar!

68 Grande wrote:
The far left two fasteners and the most difficult to access are "screws" (#11) and not speed nuts. Cliff`s diagram shows that and that is the way my 68 was as well. Big PIA accessing those screws.

The screws (#11) only hold the fan onto the housing, and don't need to be removed when removing the heater box on the interior of the car.

oshawacliff · Poncho Master!

so is it your intention to remove the box under the dash?

cdnpont · Canadian Poncho Superstar!

I have to Cliff. There is something long dead in there. Very little airflow. I suspect a bunch of seat stuffing blocking the airflow.

Canadian Poncho · A Poncho Legend!

It almost sounds easier just to remove the fender.

cdnpont · Canadian Poncho Superstar!

I don't think it will be a big deal to drill off the backside of the box stud. But I'll try to snake my hand in around the box first. Maybe make a McGiver wrench or something. I also have one of those snake camera's. It might help.me see the nut.

Pontiacanada · A Poncho Legend!

cdnpont wrote:
Maybe make a McGiver wrench or something. I also have one of those snake camera's. It might help.me see the nut.

Good ideas ... let us know how you make out.

Mike Ward MB · Addicted!

seventy2plus2 wrote:
The screws (#11) only hold the fan onto the housing, and don't need to be removed when removing the heater box on the interior of the car.

#11 are machine screws and they do mount the cover to the firewall. The fan is mounted to the cover with four or five screws.

I fought with my cover for a while. The car ended up coming apart anyway so I didnt waste too much time trying to get it out. That was the first thing to go back in before reassembling the front clip.

The easiest way to get it off is to remove the inner fender unfortunately.

-- Edited by Mike Ward MB on Tuesday 20th of November 2018 07:57:36 PM

68 Grande · Guru

cdnpont wrote:
I have to Cliff. There is something long dead in there. Very little airflow. I suspect a bunch of seat stuffing blocking the airflow.

Yep, you have to open it up if you have deceased critters in there. Only way you can clean it up.

I would bleach the inside of that box once you open it up and I would be wearing a mask and a running vacuum when initially digging out the contents. Just me, but I have cleaned too many grain bins and farm vehicles where critters were an issue.

cdnpont · Canadian Poncho Superstar!

Yes, I'll be careful and wear a mask for sure. When I turn the fan on in the car, it smells pretty toxic. Took the back seat out, and it was bad enough.

I remember I had the box out of a 69, and It could not be opened up to clean it out. It was kind of permanently put together if I recall.

Can it be opened up, taken apart to really clean it up?

oshawacliff · Poncho Master!

stuff to sell on Ebay Mar 12-15 (23).JPG quick photos

stuff to sell on Ebay Mar 12-15 (25).JPG

stuff to sell on Ebay Mar 12-15 (27).JPG

I can take more photos later

seventy2plus2 · Canadian Poncho Superstar!

Mike Ward MB wrote:
seventy2plus2 wrote:
The screws (#11) only hold the fan onto the housing, and don't need to be removed when removing the heater box on the interior of the car.
#11 are machine screws and they do mount the cover to the firewall. The fan is mounted to the cover with four or five screws.
I fought with my cover for a while. The car ended up coming apart anyway so I didnt waste too much time trying to get it out. That was the first thing to go back in before reassembling the front clip.
The easiest way to get it off is to remove the inner fender unfortunately.

-- Edited by Mike Ward MB on Tuesday 20th of November 2018 07:57:36 PM

You're right about the screws holding the cover to the firewall (I was looking at the photo on my phone) However he's trying to remove the heater box on the interior, so the cover can stay on the firewall.

cdnpont · Canadian Poncho Superstar!

This is true. I could probably get away with removing just the inner box. I'll do that first. But I suspect the squirrel cage fan along with the plenum is probably filthy as well.

I went out and had a good look at it. I think I can get to the outside lower #11 screw with a little bit of inventiveness. The hood will have to come off, as the passenger hinge will be in the way if I want to pull the outer box out.

I really don't want to go to the trouble of removing the fender. The hood is less work.

Mike Ward MB · Addicted!

You can remove the inner box without fully removing the outer cover. Following my nose, I removed mine in search of an obviously dead rodent. Unfortunately it met its maker in the fan. Turning the fan by hand, a nose appeared and I was able to remove the carcas, but my fan was stuffed full of parts of my upholstery that I couldnt get at without removing the cover from the outside.

Tin Injun · Addicted!

I had to do this on my '68 and this is not a job you want to do twice. I have small hands and with minimal cursing and maximum patience, I got the hidden nuts off by feel and just pulled the interior box with the core attached. Removed the leaking core, replaced with non-leaking core and reversed the procedure with a hand from a friend who held the outside cover in place while I tried to get all the studs lined withe the outside holes. Also had him start a couple of the nuts to hold it in place until I could take over.The bottom core pipe has a bend in it that makes it hard to get everything in the correct place. Had to use a round file to open the hole enough to get it through.

I used a stubby box end wrench to get the hidden nut [ farthest toward the fender] off but found it impossible to get it in place to re-install it,so, it is now in my spare nut bin. Didn't bother with the heater motor and hope it never has to be replaced!

Fred

cdnpont · Canadian Poncho Superstar!

I'm going to try removing the passenger side hinge only. I'll ratchet strap the hood from the front and back, with straps into the rafters above.

I think with the hinge out of the way it might help me get up, over and behind the blower.

The inner box is really rusty. Like, probably ruined. Apparently water came into the car through the box. How does that happen? Does it come in through the cowl plenum, then down into the blower plenum eventually spilling into the inner box?

Or is this an issue with the body itself? It's not a leaky core. One thing; it looks like a new windshield is now in place with plenty of sealer on the inside. But the dash panel looks completely fine. Maybe it leaked through the windshield? Guess it will be obvious when it gets opened up.

4SPEED427 · A Poncho Legend!

A very common issue on these cars if they've been sitting outside is rust in the lower windshield channel. I won't be surprised if that is what has happened, especially when you say it has a new windshield.

I've seen the passenger front floor pan rusted out because of this issue.

68 Grande · Guru

I took my hinge off as well and removed the inner fender tub, and the engine was out for a re-fresh. But, I had that aftermarket GM air cond unit inside to contend with as well so I could not completely remove the inside box. I could see some rusting on the air direction door inside the inner box, looking from the outside in, but mine was not too bad. The foam seal around the door was decayed and I bet yours is as well. I shot a bunch of rust paint in there as best I could. And, while I was at it, I noticed that my windshield channel at the bottom of the windshield had been replaced at some point. This is likely a reason my lower door pillars will need some attention at some point.

Keep us posted on your "morbid" findings. I hate mice.