I am working on a friend's 1914 Model T and have run into a snag in regards to the transmission. This engine/transmission has mixed and matched parts, such as a single stack coil ring with oval centers. Perhaps the driving plate has been changed, too? Are the driving plates interchangeable prior to 1926? The one on this transmission is not riveted underneath and has large push pins holes, while a plate I have on the loose is riveted and has smaller push pin holes. Everything else seems to the same between them, other than the number of holes around the center. I should think the riveted driving plate is the early one, even though this transmission's driving plate is not. Because the shaft collar is in better condition and fits nicely inside the newly-rebabbited 4th main than the one that was on this transmission, I'd like to use the extra driving plate instead. Can I do this? Are they interchangeable? If the early driving plates were riveted, that means they should be interchangeable because the plate on this engine (as stated) is NOT riveted (a later driving plate?).
Thanks to Gene Nelson of Davenport for coming over to my house today and answering my stupid questions about Model T transmission problems and sharing the fine points of recharging the magneto while out of the car. He even did a chemical magnet check for cracks! Nothing beats experience and a willingness to share it! Thanks again, Gene!
Marshall
Unless I misunderstand, all the driving plates are riveted to the output shafts. I also believe they are all interchangeable up to 1926.
Be mindful of the dowels on the clutch pack ring. The rings with large dowels can get stuck in driving plates with smaller holes.
I will not say how I came to know of this.
Whenever I needed to have my ball cap (4th bearing) rebabbited by George King III, he asked that I send him the drive plate along with the ballcap so that he could be sure the babbitted bearing could be custom machined to the diameter of the shaft so that the fit was as close as possible.
While the drive plates are probably interchangeable, some may be worn more than others, so that the diameters are not the same from one to the next. If you install a worn drive plate shaft on an engine with worn ballcap babbit, you're going to have a very bad leak. If you install a drive plate with little shaft wear, on an engine with a newly babbited ball cap, the shaft might be too tight for the ball cap. so the best case scenario is to send the drive plate and ball cap off to George King III to be babbited and fitted to the shaft. Jim Patrick
I plan to use the clutch pack ring that goes with the driving plate I have on the loose. That way the pins and holes match.
Marshall
I believe that Jerry pretty well answered the question. The question still remains as to the welded driving plate being found in a 1914 transmission. Was this stock for that year, or did someone weld up a previously riveted one? If that is the case, Mashall can go ahead with using one which is in much better condition. As mentioned above, this car has several mixed parts that had been working together.
Owner constraints prevented the removal of the magnets for the "crack" test, so we did the Dye Check test at the V area of each magnet, while in place. No cracks were found. Had cracks been found, there would be no choice but replacement.
Gene