Sean's Bonny Motor Rebuild

12/16/04, 12/28/04, 1/29/04

Transmission build. Inspection revealed worn main drive gear bushing and first gear c-shaft bushing. Notes below.

notes:

Press out old main drive gear bushing. Install new bushing. Hone to .0015 loose fit on mainshaft.
Make new first gear countershaft bushing and hone to .001 loose on countershaft. Used sintered bronze bushing stock.
Installed main drive gear in case with new bearing. Install new sprocket and lock-tab washer. Used anaerobic sealer on gear splines.
Deburred/cleaned up shift quadrant channel for smoother shifting. Replaced "hat" bearings that ride on shift forks.
Inspected shift fork rod for nicks/burrs/wear. No problems found.
Installed new shift quadrant spring and plunger.
Inspected all gears for chips/cracks/wear. No problems found. Gears in very good shape.
Turned down previously damaged lip on mainshaft that was preventing smooth installation through inner trans cover bearing.
Helicoiled six damaged thread bosses on left case at transmission and on inner transmission cover.
Made two new inner trans case studs. 5/16NC - 5/16NF as I don't have Brit thread repair kit. Fine threads into soft casting as with oem is weak anyway.
Installed mainshaft and countershaft gear clusters in case with new countershaft thrust washers.
Installed transmission inner cover and time shift quadrant with shifter plate.
Made new kicker clutch gear spacer as old one damaged.
Installed kicker clutch gears with new spring.
Made and installed new kicker return stop. Old one severely worn and case boss damaged. Was leaking trans fluid. New one is .002 press fit in inner trans cover.
Made and installed new kicker shaft bushing in kicker cover. Old bush was over .007 loose and was leaking trans fluid.
Turned and polished kicker shaft .005 undersize and fit new cover bushing to .003 loose. Shaft was severely scored and pitted.
Installed new kicker shaft oil seal and washer.
Installed new kicker spring.
Disassembled, inspected, rebuilt shifter return mechanism with new return springs.
Disassembled, inspected, rebuilt clutch release mechanism. No problems found. Shifter shaft is close fit in existing bushing.
Reformed damaged filler cap boss threads in kicker cover with jeweler's file. Filler plug would not install previously.
Installed trans drain plug, kicker cover, filled with 700cc 75/90 hypoid gear oil.
Confirm correct shift timing with all four gears accessible.