105643-0220 ZEXEL 9 420 615 646 BOSCH AUTOM. ADVANCE MECHANISM 9420615646 1056430220 me716934

start by: a) remove flywheel housingb) remove crankshaft rear seal 1. Turn the crankshaft until the access holes in gears (1), (2) and (3) are in alignment with the nuts or bolts that hold the thrust washers to the timing gear plate. Turn the crankshaft more than one time if necessary to remove all of the nuts and bolts from the thrust washers. Do not remove any of the gears at this time.2. Turn the crankshaft to top center of compression stroke for No.1 piston. See LOCATING TOP CENTER FOR NO.1 PISTON in TESTING AND ADJUSTING.3. Install a 3/8"-16 NC eyebolt in drive shaft (6) and remove it from camshaft drive gear.
Do not turn crankshaft after drive shaft (6) or any of the gears are removed or damage to the pistons and valves will be the result.
4. Remove bolts (4), locks (5) and the hub from gear (7). 5. Remove the bolts, lock and washer to remove air compressor drive gear (8) from the timing gear plate. 6. Use tooling (A) and a press to remove the bearing from gear (8) as shown. 7. Remove gears (1), (2) and (3) and the thrust washers from the timing gear plate. 8. Use tooling (A) and a press to remove the bearings from gears (1), (2) and (3) as shown. 9. Turn gear (7) to make an alignment of the access holes in the gear with bolts (9). Remove the bolts, gear (7) and thrust washer from the timing gear plate. 10. Use tooling (A) and a press to remove the bearing from gear (7) as shown.Install Timing Gears
1. Use tooling (A) and a press to install the bearing in gear (1), until the bearing is even with the surface of the gear. 2. Install gear (1) and thrust washer (2) on the timing gear plate and tighten the bolts and locks to hold the thrust washer. 3. Use tooling (A) and a press to install the bearing in gear (3), until the bearing is even with the surface of the gear. 4. Use tooling (A) and a press to install the bearing in gear (4), until the bearing is even with the top surface of the gear as shown. 5. Put the bearing in position in compressor drive gear (5). Make sure that the reliefs in the bearing are in alignment with the reliefs in the gear. Use tooling (A) and a press to install the bearing even with the surface of gear (5) as shown. 6. Install the bearing in gear (6) with tooling (A) and a press until it is even with the surface of the gear.7. Make an alignment of the "V" mark on gear (3) with the "V" mark on the crankshaft gear and install gear (3) and the thrust washer on the timing gear plate. Tighten the bolts and lock to hold the thrust washer. 8. Make an alignment of the "V" mark on gear (4) with the "V" mark on gear (3) and