The rear main thrust wears on the front end due to the clutch spring hauling back on the crank when the clutch is released. May I respectfully suggest you put the shim on the front end of the cap so the magneto clearance remains in specs. I think your method in ingenious. I have done this repair job a few times but don’t advertise it. I build up the babbit surface on the front of the cap and machine it down to proper width. It’s crude but works fine. Model T respond well to such things. When I babbit model T’s I put a bronze thrust on the front of the rear cap and it solves the problem permanently.
Sorry for my delay here. Crankshaft end play, when excessive, begins to cause fly wheel parts, mostly magnets, coils, etc, to begin hitting each other as tolerances are set very close for the magneto to work properly. End play caught early will save a lot of repair and problems, but correction is problematic. My scheme outlined in this video is a takeoff of similar fixes found. Best simply do an external end play measurement as described, it will tell you all thats needed as to your next step.
Did you have a noise when driving of the crank shifting through block? My 26 just started. If I go in reverse I get a noise when it shifts one way then only does it once again when going forward. I may try this to fix it. Thanks for the video
Actually, only one half the bearing controls the crankshaft thrust, and the repair here was to place a spacer, the brass shim seen, of sufficient thickness to make up for the loss of Babbitt for this repair, and in the future, well another problem comes up. The unworn space between the crank shaft flywheel flange and the other side will not allow more thickness to pass by when added to the bearing half, so then another tear down, a reworked crank, new fitted bearings, a ton of time and bucks, and all done again. I suspect one more thicker brass shim might be possible, but I would not bet on it. But, it did save a lot this go-round.
