Plymouth Owners Club

Does anybody know where on the web..,? I can view a diagram of the driveshaft joints on the 28/29 Plymouth.? They appear at first glance to be two flanges bolted together with some type of material between them.?? ?Obviously I haven?t spent much time under this car yet, just curious about this odd looking setup.

Chet?

The "universal" on the early Plymouths was a fabric disk. Apparently you can still get it, see:

http://www.ply33.com/Parts/Group16.html

However I hear that it is quite expensive. Check the classified ads in the back of the Plymouth Bulletin. I think a club member is making and selling them for less money.

Quote from: chetbrz on November 27, 2006, 12:34:16 PM
Does anybody know where on the web..,? I can view a diagram of the driveshaft joints on the 28/29 Plymouth.? They appear at first glance to be two flanges bolted together with some type of material between them.?? ?Obviously I haven?t spent much time under this car yet, just curious about this odd looking setup.

Chet?

Thanks..., I first looked on your site but didn't use the Alphabetical Part Group listing.? Now that I know it?s there I will use this first.?

Bye the way?,? How does this universal joint work.?? How does it account for propeller shaft movement up and down which would shorten and lengthen the distance from the differential to the transmission.?? Do I have this correct and is it compressing the material between what appears to be the flanges.? Or is something else happening.?

Sorry just learning?? Chet?

PS? If I need one of these can I order the (John Deere L373T -1940 John Deere LA tractor) from any Deere dealer.? There is a big Deere farm supply house in Harrington Del.

Quote from: chetbrz on November 27, 2006, 12:34:16 PM
Bye the way?,? How does this universal joint work.?? How does it account for propeller shaft movement up and down which would shorten and lengthen the distance from the differential to the transmission.?? Do I have this correct and is it compressing the material between what appears to be the flanges.? Or is something else happening.?

As if you make the rear axle swing along an arc so that the radius is centered at the end of the transmission there will be no change in length in the drive shaft. A lot of cars made use of this principle in the old days. Just look at any Model T or Model A Ford. I believe that Buick and a number of GM cars did as well. I believe they called it "torque tube".

However the Plymouth has an open drive shaft and no obvious way of assuring that the rear axle would travel in an arc to keep the length of the drive shaft uniform. So I guess I will have to say that I don't know how it works.

And since my car has the (in)famous "Detroit" ball and trunion universal joints I don't have any direct experience with the fabric style versions.

Fabric u-joints were? used on a lot of early vehicles, not just Chryco products. They compensated for driveshaft length changes by flexing within the fabric. Most joints I have seen consisted of four "fingers" on each of the drive shaft ends and trans/pinion shafts. The fabric was bolted to the trans output shaft, and the driveshaft fingers were offset 45 degrees and also bolted to the fabric. Same thing at the diff pinion. The flex in the fabric allowed for the minor changes in d/s length as the springs flexed and also allowed the "misalignment" of the d/s as it turned.

Quote from: 12905 on November 28, 2006, 04:21:13 PM
Fabric u-joints were? used on a lot of early vehicles, not just Chryco products. They compensated for driveshaft length changes by flexing within the fabric. Most joints I have seen consisted of four "fingers" on each of the drive shaft ends and trans/pinion shafts. The fabric was bolted to the trans output shaft, and the driveshaft fingers were offset 45 degrees and also bolted to the fabric. Same thing at the diff pinion. The flex in the fabric allowed for the minor changes in d/s length as the springs flexed and also allowed the "misalignment" of the d/s as it turned.

A few people have told me that this type of universal is a little dangerous and needs to be checked regularly.? Suspecting that this is true.., do you know what would be considered a good check for these joints.??

Chet...

They're not dangerous if they are in good health. They can rip and let the shaft swing free but I've never actually seen or heard of it happening now in the hobby. Maybe when they were a daily driver and nobody paid any attention to the condition of the discs. But I know of several cars both Plymouth and other makes that have their original disc system in place and have never had any problem from them, and you don't have to grease them!! The car only produces 45 horsepower and that's at wide open throttle at max revs. You are maybe putting 15 horsepower down the shaft at 35/40 miles per hour. I believe there was 5 discs ,3 up front and 2 rear, if memory serves me correctly. I would think if you put in new or NOS discs they will out last your use of the car. I have driven a '29 to shows and on tour,it wasn't mine, and you wouldn't know it had rubber/fabric discs for universals.       

Contact       He has new ones available. I just received a new set today. They are perfect.