For the TR4 transmission in my TR3 I just got the transmission top cover drilled and threaded for the overdrive switches. The machine shop used the diagram from the TR4 manual for placement of the holes, and they are perfectly placed. The problem/question I have is that the "detent" in the 3rd/4th gear selector fork for the overdrive switch is almost 3/4 inch wide. (It is a Stanpart selector fork p/n 137387 with an AB2 below the part number.) As can be seen from the attached pictures the raised area that is supposed to turn the overdrive on in each of 3rd and 4th gear ends up positioned where the switch ball just barely gets pushed up, i.e. it rests on the very edge of the raised area. This seems as though it could cause intermittent overdrive switch problems after a bit of wear. Has anyone experienced this with the 3rd/4th gear selector fork? Is it possible, (or wise) to have the machine shop braze and machine the selector fork to make the detent about 1/8 inch shorter on each end of the detent?
BTW, the second gear switch is exactly over the top of the raised area on that selector fork and the detent moves correctly under the switch when shifted out of 2nd gear.
Regards, Bob
BTW, the second gear switch is exactly over the top of the raised area on that selector fork and the detent moves correctly under the switch when shifted out of 2nd gear.
Regards, Bob