MikeC5 Posted October 14, 2012 Share Posted October 14, 2012 There doesn't seem to be anything out there on these vacuum wiper motors so I thought I would post some pictures of disassembly of one. I have been trying to find a Folberth vacuum wiper motor (pre-Trico) but sources tell me the poor pot metal castings making up the bulk of them are very difficult to find in usable condition. As near as I can determine, my 1925 Dodge Brothers touring car originally would have been equipped with a Folberth (it had a half moon-style Trico retrofitted at some point in time). I did see a few of these Eveready vacuum motors at Hershey and picked one up for a reasonable price. I'll still keep an eye out for a Folberth but I figure at least this is of similar cylindrical design. It was very easy to take apart; oddly, the end caps seemed to use only a tight fit (or perhaps a thin layer of glue?) to hold them on. There was no trace of solder... Link to comment Share on other sites More sharing options...
MikeC5 Posted October 14, 2012 Author Share Posted October 14, 2012 Forgot a photo of assembled... Link to comment Share on other sites More sharing options...
MikeC5 Posted February 8, 2013 Author Share Posted February 8, 2013 Well I'm hoping someone has one of these with the rotary valve intact. I've tried to reverse engineer how this worked and although close, I can't quite get it the piston to make the full stroke and then reverse direction. It stops when the lever gets about 1/2 way over and can't quite reverse the vacuum. The first photo shows the basic idea. The piston shuttle is one piece with a piston on each end. There is a small tang near each piston that trips the rotary valve actuating lever as the piston nears the far end of its chamber and reverses the application of vacuum to the opposite piston. The back of forth of the shuttle is translated into rotary left-right via the sliding track on the shuttle and the pins on the end of the wiper shaft (in first series of photos). Unfortunately, the rotary valve in this unit was missing so I'm guessing how it did its thing for my recreation in pic 3 and 4. I would really like to get a peek at how an original valve looked. I think it may be a timing issue/placement of vent holes... Link to comment Share on other sites More sharing options...
R.White Posted February 8, 2013 Share Posted February 8, 2013 How did you superimpose the diagrams onto your photos? I am not very knowledgeable about these things.I have never had much success myself with restoring vacuum wiper motors so a detailed restoration feature would be a great help. At least you managed to establish that you are missing some internal part. There seems to be quite a few non - working wiper motors about, so hopefully you will be lucky in finding another one for parts. Best of luck.Ray. Link to comment Share on other sites More sharing options...
Pete K. Posted February 8, 2013 Share Posted February 8, 2013 Thanks for posting that Mike. Our '25's must have had a cylindrical type motor like your Hershey find, only a Folberth like we all have mentioned. I've been studying your pictures, but have come up empty on a cylinder valve for "production" to get that working. It's one of those things where I would have to have it in my hands to really project a thought on making a valve. Keep at it though, it would be worth it to put on the '25. Best, Pete. Link to comment Share on other sites More sharing options...
ply33 Posted February 8, 2013 Share Posted February 8, 2013 Maybe there is a patent number on it? I think there are some look up tools on the web where you can get the patent application copy for free and read how it is supposed to work. Link to comment Share on other sites More sharing options...
Machinist_Bill Posted February 8, 2013 Share Posted February 8, 2013 Maybe there is a patent number on it? I think there are some look up tools on the web where you can get the patent application copy for free and read how it is supposed to work.Excellent idea!!! I have to go to work in a few minutes but tonight will dig out my one and only "Folberth" and list the patent numbers here. Link to comment Share on other sites More sharing options...
dl456 Posted February 8, 2013 Share Posted February 8, 2013 I think that I still have two Folberth vacuum motors that I purchased years ago at Hershey. If I recall one appearsnos. These have been stored away for a number of years. At one time I was buying most that I found in an attempt to make a good one. Didn't Folberth also make an air motor for trucks that looked almost the same?If there is any interest, I will take a look this weekend.Dennis Link to comment Share on other sites More sharing options...
MikeC5 Posted February 8, 2013 Author Share Posted February 8, 2013 Hi Ray, I happen to be using Corel Paintshop Pro for drawing the diagrams on the photos. Most image processing software (Adobe Photoshop, etc.) have a feature to allow this type of thing. I have done work on old player pianos before and those a vacuum-based systems so... Good idea bout the patents.. worth a try. Dennis, if you can find these and they are actually vacuum motor (as opposed to the similar looking air pressure motors) I would certainly be interested in seeing photos of them. Link to comment Share on other sites More sharing options...
Machinist_Bill Posted February 10, 2013 Share Posted February 10, 2013 Here are some photos Mike of my Folberth. Link to comment Share on other sites More sharing options...
MikeC5 Posted February 10, 2013 Author Share Posted February 10, 2013 Thanks Bill. So this is the type that usually has the pot metal casting coming apart? It looks good in the pics. Does it operate? I'll have to see if I can chase down anything on the patent date although my first attempt to search on the govt site was unsuccessful for the Eveready (which shows no patent numbers or dates). Searching by subject turned up nothing but I think one really has to read up on how to do searches. It's fairly complicated imho... Link to comment Share on other sites More sharing options...
Machinist_Bill Posted February 10, 2013 Share Posted February 10, 2013 I think ANYTHING made with pot metal in the 20's crumbles into dust! This one however avoided moisture so it's not in bad shape. I used the wiper assist lever and it moves back and forth so worst case scenario I can use it manually. Is there anything I can make for you to get yours going? Link to comment Share on other sites More sharing options...
MikeC5 Posted February 10, 2013 Author Share Posted February 10, 2013 I really appreciate the offer Bill but at this point I'm not sure what to make. The white piece (rotary valve) in the photos I made out of delrin. I have a lathe (old 9" South Bend) to turn the basic shape and then careful application of a small Dremel bit to hog out the groove. A hand file makes the flats on the end of the valve that mate to the lever mechanism. The lever mech has a spring loaded detent the limits movement to +/- 30 degrees from vertical center line. I suspect the 'timing' of when the groove connects vacuum source to port and when the vent hole releases vacuum at the opposing port is key to make this work. I've experimented with a couple of other timings but no luck. Link to comment Share on other sites More sharing options...
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