Restoring a Mopar Deluxe Model 31 Heater

[lostviking]

I'm starting a new thread to show this restoration, rather than continue to use the "What Heater fits..." thread I started when I was trying to find a heater. I'm not going to move the content related to the restoration, but you can still see it here:

 

The beginning of the project to restore the heater is there, I'm picking it back up with the rust removal of the rest of the box and associated parts. Today I did the first half of the main box. I again used a power supply and a bucket of water with Washing Soda it in. The details can be seen on the previous thread. Nothing new there. I am using the currently limiting resistor this time of course to avoid damaging my power supply, again. Due to other resistances in the circuit, namely I didn't bother to get a perfect connection from my negative wire to the metal, the current was about 1.36A. That's based upon there being a 6.82ish volt drop across my 5-Ohm resistor. Ohms law.

 

I didn't take a picture of the metal before, but I do have the other side and the first part I did today. I left it in the bath for around 3 hours. There is a very minor amount of rust in some places. Most people might just use a spray over rust type paint, but I'm going to put it back in the bath tomorrow to finish the job.

 

Looking at these pieces to take pictures, I see the worst part is the ones I've already done. I still wouldn't paint over this rust. A side benefit of the electrolytic rust removal, is that is take all the original paint off too

 

Edited August 1, 2020 by lostviking
Added some pics

[lostviking]

Here is the other half before I ran it through the bath. The pictures above had the same paint (some still there), but the electrolytic process takes you down to bare metal. I'll need to get some more VHT self-etching primer to protect the metal once I wash the parts post rust removal.

[lostviking]

The medallion and the hands/tabs on the various doors are riveted on, so I'm going to have to dremel them off before I do any painting. I'm also going to remove the screens. The just have some small tabs bent over them. Easy.

[lostviking]

OK, the medalion was just bent tabs, so that came off easy. The little door handles took a drill. No big. The inside of them is still rusty, so I'll put them in again. Remember when you use this process, that the electrons always take the shorted path, so if an area is "hidden" like the inside of the handles, you need to somehow make that open so there is a direct, or close line of sight. In my case, removing them was perfect.

 

I dipped the first have of the main case again to get it really cleaned up. Only an hour, but after improving the connections of my setup, I was getting the full 2.5Amps I calculated.

 

After some minor cleanup with a fiber circular painter removal disk (fibers are like wheel spokes), I painted it with self-etching primer. Under the medalion I was able to find the original paint, which is kind of gray hammered finish. I bought some of that also. Here is the primer drying in the sun. I need to wait 1 hour to top coat. I'll post a picture of that later.

 

You can see from how smooth the primer is, that this process really gets the metal clean.

[lostviking]

Here is a first coat of the hammered finish paint. I think I like it. I didn't sand off a bit of left over paint where I circled, I should have but hey. I'll wait a couple days and sand it before I do another coat of paint. The inside I'll only do area's I might have missed the first time.

 

Not bad for an amateur and rattle cans. I'll be more careful about sanding off paint that stays behind on the remaining parts.

[lostviking]

I left the second half of the main body in the tank for 3 hours. Here it is in all it's glory. You can scroll up to see this exact view as a before. The black area's are where the rust was heaviest. Rust doesn't just magically disappear, it get "converted" by replating of the steel from the donor anodes. That looks black and can be a bit loose also. I go at that with a steel brush or wheel to remove as much as I can. The rest gets painted over.

 

Here is one coat of the same primer. After 10 mins I'll sand any rough spots and recoat. The some of the same hammer finish paint.

 

The air is pretty wet in San Diego today...gonna take a bit longer for the paint to be ready to sand.

Edited August 2, 2020 by lostviking

[lostviking]

I use Solidworks at my job, so I'm working on a model for the firewall to heater adapter shown in the manual. I've only created a rough part without the correct dimensions. I don't have one. I will look at pictures and estimate as much as I can. I'll also measure angles on the firewall to help me get this at least close to the real part. If anyone has one, dimensions would be very helpful. Even just the thickness of the metal would be helpful.

 

I'll use best practices to get it as close as I can. I'll post the drawing once I'm done for anyone to grab a copy. This is just kinda, sorta what it looks like.

 

Edit: the hole spacing is actually from measuring my heater, so that's good.

Edited August 8, 2020 by lostviking

[Young Ed]

I've got one of those somewhere. I'll try and locate it and get some dimensions

[lostviking]

5 hours ago, Young Ed said:

I've got one of those somewhere. I'll try and locate it and get some dimensions

Thanks Ed. It's not a hard part to make, even at home. You just need accurate dimensions. I'm trying to recreate the fan motor mounting pad also Again, I have a picture in my manual, which is terrible and doesn't really show it, but since my heater is all apart right now it's easy to measure things. I have to make a guess at the thickness and material. Right now I'm 3D printing something that is actually a slightly different design. I think it's a better one, but I'll see when I get it done and try it.

 

Tim

[lostviking]

Last rusty piece that needed to be cleaned up. The defroster vent from the side. Before and after.

 

Still need to brush it off a bit before I primer.

I also found some better pictures of the part I'm modeling above...I see I need another flange on the skinny end. I hope Young Ed can find his and give me some dimensions. Then we can all build one.

 

Edited August 8, 2020 by lostviking

[Young Ed]

Located it and it was actually right where I thought! 5" wide at the bottom 6.75" at the top. Left is 5.75" right 6". 2" tall bottom and 7/8 at the top. Top and bottom have a flange. Top of the holes is 1" from the top edge. 

 

P

[lostviking]

Ed, I'm trying to get all the dimensions I need from you picture and measurements. I took one of the pictures you posted, and popped it into a CAD program, then scaled it based upon the dimension you gave for the top width.

 

I'm getting all sorts of weird measurements, and I think it might be that the picture is not dead on. Could you post another shot of the part taken from directly over the part? Here's what I'm seeing, but I think there are shadows and artificial angles causing it.

 

Once I have the image in my CAD program, I can rotate or scale it...so long as I have a known dimension to measure. Maybe if that is the only image you upload, you can keep it large.

 

Thank you for your help.

 

Tim

 

P.S. Being slightly off 6.75 across the top is just because it get bleary when I zoom in to find and edge to measure.

 

Edited August 9, 2020 by lostviking

[ggdad1951]

please keep parts solicitations to PM and off the main forum.  Thanks.

[lostviking]

On 8/10/2020 at 4:09 AM, ggdad1951 said:

please keep parts solicitations to PM and of the main forum.  Thanks.

Sorry, didn't know that type of question what verboten.

 

Tim

 

[lostviking]

I've finished refinishing all the various metal parts and giving them a coat of paint. I started reassembly this morning. After "shimming" the fan motor as straight at possible with some rubber washers, I added a bit of window calk at several points around the rear of the motor. I'm hoping that will act as a vibration damper and help to maintain the center line. I put the fan shrouds on and slipped the body part with the vent openings over the other parts. No pictures yet.

I still need to repair the band of metal that acts as a sort of clamp for the two main body parts. Mine is broken at the sharp bend on one end near the threaded part. I'll try to silver solder it back together. This is a non-magnetic metal, so my options are a bit limited.

If worst case become actual, I'll find a piece of similar channel and remake that part. Probably out of aluminum. More to follow.

[lostviking]

OK, now some pictures. At some point in the very beginning of my other thread, someone asked for dimensions.

 

 

[lostviking]

Last dim.

 

 

[lostviking]

I already put the fan shroud on in those pictures, but here's a better shot...and the fan must be placed so it doesn't hit top of bottom. This is a 6V motor I got from NAPA that was intended for a 56 Chevy. I don't know yet whether I need to cut the extra length off the shaft or the through screws that can be seen sticking out the rear. If not, I'm leaving them.

 

 

[lostviking]

Last for today is the base and the body side with all the vents. The wife got home from work, so I'm done for the day. I had a day off You can see where the defroster part goes back on sticking out the side. Obviously that goes on after the body is reassembled. Even though I'm not hooking it up for now, I'm putting it back on so I don't lose anything.

 

 

[lostviking]

Oh, no screws...I'm soaking them in vinegar to get the rust off. Very minor amount and then I'm paint some Coroseal on them.

[lostviking]

Almost done  I need to repair the band that clamps the two halves, and refinish the paint on the "Deluxe" badge and the defroster pull handle. But here is what it looks like. The studs that go through the motor clear, and so did the fan shaft, so I'm leaving them alone.

 

I initially tried to rivet the door handles back on, but the nose on my rivet gun is too large and damaged the surfaces. I used screws, nuts and Loctite.

 

Just need to fabricate the mounting adapter at the firewall, and get the large nuts that hold it in. Oh, and switch, h2o valve...minor stuff

Edited August 22, 2020 by lostviking

[lostviking]

OK, I tried to repair the clamp band today. It didn't go too well. I bought some aluminum brazing rods, but can't get them to stick to the metal...so I guess it's not aluminum. Probably tin then?

 

I used my MAP torch at first, but it has WAY to much heat and the torch nozzle is too big. I ended up melting a quarter inch or so of the material away. The second thing I learned from that is that the metal ends up having a slightly yellow color after it's melted.

 

I've got another idea. I was hoping to make something that was not visible, but then this part isn't visible anyway. The place it's broken is right where it would meet the firewall.

 

The clamp band goes over the two "clam shell" pieces of the main housing. It bends towards the housing on either end, and has a long threaded piece swagged into it. The screw goes through the bottom of one of the housing halves and into this threaded part. That's what holds the two pieces together, besides perimeter screws like the two you can see directly above this.

 

I'm going to try a piece of SST tubing. Very thin wall. I'll cut it in half most of the way down, then bend over and flatten the remainder. That part will get drilled so the screw fits through. Then I'm going to use a panel bonding adhesive to attach it to the remaining part of the clamping band. I'll dress it as well as I can, then paint the whole thing. It won't be visible anyway.

 

I don't have anything I can use to repair the clamping band exactly as it was, so this I think is the best bet.

[ggdad1951]

Brass?  You could do an acid test I think to determine metal type?

 

[lostviking]

With Young Ed's help, I think I've got a pretty accurate model of the sheet metal part that goes between the heater and the firewall. As soon as I've finalized one last detail, I'll publish drawings that will allow anyone to recreate the part.

 

This is what it looks like. I need to get the proper hole sizes, and exact X, Y locations from Ed. I can also try dropping the pictures he sent me into a CAD drawing, but that will have some error to it.

[lostviking]

I spent a little time today working on a drawing for the heater adapter. Something that became obvious to me, is that the adapter Young Ed was kind enough to send me pictures of, is for a different model than the model 31 I have. The tubes for the water are closer together than for the plate he photographed.

 

I set the hole spacing at 4-5/8, which is what I can measure for my Model 31 heater. I did not change the rest of the dimensions, so only time will tell if that all still works. I'm going to fabricate one from my drawing. I'm a mechanical designer though, not a drafter. Sure, I know how...but when it comes to dimensioning a drawing per the applicable standards...well you end up with what I think I'll need. That's why we have a drafting department at work, to fix my stuff before we send it to a vendor.

 

Anyway, here you go.

HEATER ADAPTER.pdf