1940 Cadillac wing window gear box

[Gene Grundmann #15185]

The wing window gear box on my 1940 LaSalle 52 convertible is cracked where the wing window bolts to it. This is the same on 1940 Cadillac 6267 convertibles. While it still works this way, I would like to repair or replace the gear box. They are very simple assemblies but made of cast metal. Has anyone worked on these without cracking the metal? Are there new parts available? Does anyone repair them? Does anyone have good used ones? I have them out of the car and would like to rebuild them before I put them back. I would appreciate any info anyone can pass along.   Gene Grundmann  #15185    gggmag@aol.com

[Bob Hoffmann CLC#96]

Hi Gene, thanks for your idea on my post. Sort of expensive though. LOL I had the same vent reg  issues on a post recently. There was a tech fix in a Chevy club newsletter some time ago. I can't find that issue. It talked about grinding off the peened over area in order to take the unit apart. I think? that they had a kit to rebuild it, but I'm not sure. All those GM units are basically the same. Different shaft lengths & mounting.  Same old GM crap, one steel gear, one pot metal gear. Guess which one wears out first? I've seen lots of cracked housing shafts. Not sure if I wou;ld worry about it. Contact me directly if you want to discuss more. Bob

[Bill Ingler #7799]

Hi Gene: Please look at the attached picture. If you are refereing to a crack in the vertical slot at the top of the regulator that has the 1/4- 20 bolt, a crack is quit common. A result of years of cranking the vent window shut and putting to much pressure in the closed position. Another common area to have a problem with these regulators is in lubrication. The grease now inside the regulators is what was put in there when it was made. Grease then has dried up or gotten so hard, the regulator shaft when turned, pushes against the backing plate which you see in the picture, pops the rivets and off comes the plate. The regulator pictured is one I repaired for my 47 convert. In my case there was still enough of the rivet left to pean over to hold the plate after lubing the gears. If it needs repaired again then I will have to drill  through the casting and either put in new rivets or use small studs and nuts to hold on the backing plate. If the backing plates on your regulators are in place then my advice is to live with the crack because trying to replace that part alone can open up a whole new can of pot metal worms. If you want to see if someone has some used regulators then look on the back and get the casting numbers. One set of numbers should have an R or L. This does not mean that R is the right window regulator but rather it means that regulator opens to the right which means it is for the left window. At least this lettering applies to my 47 regulators and probably to yours as well.

[Gene Grundmann]

Thanks for the info Bill and Bob. I could live with the cracks at the top of regulators but they are out of the car and now would be a good time to repair them if possible. I have the bottom cover off one without any major damage and the lube inside is still very good. The pinion plate shown in Bill's photo needs to be removed along with the pinion before the main shaft and gear can come out the bottom. I was wondering if a little heat would allow the crimped retainers in Bill's photo to be reshaped for cover removal and also for re-crimping for reassembly. I have considered making special hardware to reassemble but am trying to learn from others rather than reinvent the wheel. Does anyone have a source for the hew shafts. I would prefer a new shaft to repairing the old ones.
Gene Grundmann

Hi Gene: Please look at the attached picture. If you are refereing to a crack in the vertical slot at the top of the regulator that has the 1/4- 20 bolt, a crack is quit common. A result of years of cranking the vent window shut and putting to much pressure in the closed position. Another common area to have a problem with these regulators is in lubrication. The grease now inside the regulators is what was put in there when it was made. Grease then has dried up or gotten so hard, the regulator shaft when turned, pushes against the backing plate which you see in the picture, pops the rivets and off comes the plate. The regulator pictured is one I repaired for my 47 convert. In my case there was still enough of the rivet left to pean over to hold the plate after lubing the gears. If it needs repaired again then I will have to drill  through the casting and either put in new rivets or use small studs and nuts to hold on the backing plate. If the backing plates on your regulators are in place then my advice is to live with the crack because trying to replace that part alone can open up a whole new can of pot metal worms. If you want to see if someone has some used regulators then look on the back and get the casting numbers. One set of numbers should have an R or L. This does not mean that R is the right window regulator but rather it means that regulator opens to the right which means it is for the left window. At least this lettering applies to my 47 regulators and probably to yours as well.

[Brad Ipsen CLC #737]

I have taken these apart on a 40-60S similar to what Bill describes.  I didn't try to reuse the pot metal body rivets that Bill points out.  I drilled and tapped them and used screws.  This worked well.  At 90 degrees to this is a sheet metal cap that is held by bent pot metal.  There are enough extra tabs here to reuse.  38 to 40 seem to be quite similar and then there is a change in the basic body in 41 from what I see in my parts.  I used a 40-5219 for spares for the 40-60S.  I don't remember all of the interchange possible but a right rear interchanges some parts with the left front which is usual the only one wore out.  They work a lot better when they are re-lubed.  I have never seen any new parts for these but I still have some good extra parts around.