Borg Warner Overdrive Problem

J

jeepguy1948

Well-known member
So, I bought a Borg Warner overdrive for my Model A and discovered that the 6 Spline X 18 Spline coupling for the connection of the rear overdrive shaft to the pinion stub shaft. The overdrive is useless without it. A fellow in Longview Washington made several thousand of these so I’m hoping somebody has one they will part with. I do not know if this is a custom coupling or if it was OEM for something.
 
I would try Valley Gear in Seattle (800) 874-4408 I think they are a fairly standard coupling for agriculture/PTO type stuff
 
Have you tried contacting whomever you bought the OD from? Maybe they have the part you need and forgot to include it in the shipment?
 
Back in the 90's we installed a number of the Borg Warner overdrives that Burt Hiller made and these only had 6 spline couplings connecting the OD output to the stub shaft.
But as Rotorwrench suggests there were a few others who offered converted BW units back in the day and such a coupler combination (6 to 18) could have been used.
Recently the only overdrive stub shaft I've seen with 18 splines was in the Laycock (Volvo) overdrive made by Rich Little.
 
They look similar to the BW type but there are distinct differences. Maybe a previous owner picked that stub shaft up for a Laycock hoping it would work. No telling. A stub shaft could be cut & re-splined for a Ford 6 to 6 spline coupler. Those are out there. 18-spline, I don't know.
 
Thanks for the input guys, I really appreciate it. I purchased the OD from a gentleman about 100 miles from my so so I went and picked it up in person. The seller is adamant that he gave it to me. It’s possible he did but if that’s the case it’s disappeared, I have torn apart every place it might possibly have passed through. Personally, I think it’s laying around in his barnyard somewhere but he says no way so I’m at a dead end there. The seller told me that it went together like a V8 driveline does. I’ve never seen a V8 driveline apart so I can’t say. I will follow up this coming week and try to contact the possible sources suggested. My guess (and it’s only a guess) is that that particular OD was out of a vehicle (International, Studebaker, Chevrolet, Ford, the list goes on and on) that used the 18 spline shaft. As I understand it the V8 Fords used 6 and 10 spine shafts.
 
The early Ford V8 differentials had a 10-spline pinion early on and around 1938, they went to 6-spline pinions. The Ford and Mercury cars both used R10 BW overdrive starting in 1949 but their tail shaft is slined to fit a slip yoke for open drive.

I don't know what the model A BW conversions used. They weren't going to use a slip joint for a torque tube so they were likely modified for the spine coupling like the 38 thru 48 cars used. They were pinned to the pinion shaft but the pins like to break and fall out now and then.
 
I did some further reading on these old conversions since my own experience with them is limited to the Ford and Mercury cars of the late 40s & early to mid 50s. From what I understand, there were more than just one or two fabricators that attempted to make their own conversions for the model A cars & light commercials. Some were reliable and some were not, so a lot depends on who built the unit that the OP is needing parts for.

Bert Hiller was known to make the most reliable units since he paid particular attention to proper alignment of the modified torque tune sections. He made the flanges very thick so that they couldn't distort in service. They were near 1-inch in thickness. He also set up the rear seal to be as reliable as he could find since unseen oil leakage and subsequent lubricant starvation has be the most common killer of the planetary system. He used the short case units that were common on Nash and Studebaker cars. This set up utilized the torque tube as most of the structure and kept strength to a maximum effort in engineering. His units all share these characteristics so they are pretty easy to identify. Any unit that doesn't share these characteristics is in that unknown reliability range that is less desirable.

Bert Hiller retired and sold his business to Bill Swigart in Redding, CA. I found an obituary for Bill Swigert on line so the chain of support for these units has likely come to an end.

There are companies that will fabricate any kind of spline adapter a person wants out there. They would need the shaft diameter and spline count to start along with the width of the spline. Female to female adapters can be broached or machined depending on how the shop doing the work is equipped. Length dimensions will also be needed to get he stub shaft in the right place for fit to the differential pinion location. The seller of the OP's unit didn't do any favors by omitting a key part of the unit assembly since it rendered it useless for anything but parts.

The other option is to sell it for parts and purchase a modern Mitchell overdrive. There may still be some folks that play around with the Volvo/Laycock units but it's hard to beat the Mitchell.
 
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Well, the simple truth is that the parts might be worth a $100 and that would only cover the shipping on the Mitchell, the unit itself is over $2k. I do appreciate the research you did although so far nothing has come up to explain exactly how the connection was made at that joint. I believe that this is a Hiller unit because everything looks very well made and a described and also, I am in wester Washington about a hundred miles from where Heller’s shop was. I would suspect that even Heller’s were not all exactly the same because he would first have to start with a do salvaged from one of the different manufacturer’s that used them. Mel Gross and a partner used to make these units also but both Mel and his partner are now gone and his son Randy was not yet involved in the business at that time so does not know how they did it and has no parts. Randy did suggest a couple places to check which I will do this coming week.
 
There is a company in Kentucky that deals with Borg/Warner transmission conversions: Transmission Exchange, Monticello, KY Phone (606)348-8533 Good luck!
 
Gary, I tried Valley gear, it appears that they are out of business I tried the 800 number you gave and also looked up the local 206 number, disconnected.
 
I remember talking to Ron Mosher of Newhall CA some years ago and I believe he bought the inventory of Bill Swigert. Maybe Ron has some parts you can use.
 
Ok well, some new info; first, shame on me, the spine count on the aft end of the OD output shaft 16 Not 18 as I previously said. So, it’s. Very hard for me to explain this in writing but I’m going to do my best; the shaft that exits the back of the OD I’m calling the output shaft. The output shaft has 16 splines. The diffential has what I am calling a stub shaft that is approx 10” long and has the pinion gear attached to one end and 6 spines on the other end (I am told that this a V8 type of arrangement but I’ve never seen one myself). The 2 shafts connect with the use of coupling that has 16 female spines on the front end 6 female spines on the back end (again, like a V8 except with 16 spines on the front not 6 or 10 Like the V8 has). To make it even more complicated to explain the coupling itself passes thru a seal in the torque tube. The coupling attaches to the pinion stub shaft with a pin thru it like a V8. I have been assuming that this was one of Bert’s because I found this OD 100 miles from where his shop was. I have been contacted by a lot of people trying to help me but nobody has ever seen one of this type.
 
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