Assembling Crankcase Halves

1. Clean gasket sealing surfaces of crankcase halves.
2. Bolt together crankcase halves and measure bearing housings in crankcase. Bore diameter should be 2.55095-2.5598 inches.
3. Recondition main bearing bores as necessary.
4. Clean out all oil passages and blow clear using compressed air. An annular groove is cut around main bearing No. 7 through bolt on lefthand crankcase half sealing surface. Keep groove free of dirt or sealing compound.
5. Place intermediate shaft with connecting shaft and oil pump in crankcase without drive chain.
6. Turn intermediate shaft by hand and ensure that intermediate shaft, connecting shaft and oil pump turn and mesh smoothly. If any out-of-roundness is visible, gear teeth in mesh must be altered until all parts rotate freely.
7. Remove intermediate shaft with connecting shaft, but do not separate gear wheels.
8. Place drive chains on intermediate shaft chain wheels.
9. Insert sealing ring in oil passage between righthand crankcase half and oil pump housing.
10. Install intermediate shaft with oil pump into righthand crankcase half with new tab washers and nuts, then torque nuts to 18 ft. lbs. and bend up tab washers.
11. Place main bearing shells for bearings 2 through 7 in position in both crankcase halves.
12. Place shells for main bearing No. 1 in position in both crankcase halves.
13. Install crankshaft with bearing No. 8 into right crankcase half.
14. Coat shaft sealing ring at outer extremity with suitable sealant and install flush with exterior of crankcase half.
15. Position and tighten retaining clips for connecting rod and chain.
16. Position sealing rings between oil pump and lefthand crankcase half and the sealing ring linking oil passage between two halves of crankcase.
17. Apply thin coat of suitable sealant to mating surface of crankcase.
18. Install tools P221 and P222 or equivalents in right crankcase half.
19. Install lefthand crankcase half.
20. Assemble through bolts as follows:
a. Install double chamfer washer in bore so that smoother surface faces crankshaft.
b. Push on O-ring.
c. Push through bolt into position from righthand half of crankcase.
d. Place O-ring on end of through bolt.
e. Install second double chamfer washer so that smoother surface faces crankshaft.
f. Install cap nut. Bearing No. 1 has studs for attachment rather than through bolts. The studs are inserted into the lefthand side below oil cooler flange. Sealing rings and nuts must be installed as described in step 20.
21. When attaching main bearing No. 7 to stud in chain housing of lefthand crankcase half, use standard washer and nut.
22. Torque through bolts and studs evenly across crankcase to 25 ft. lbs.
23. Use No. 8 spring washers on all crankcase retaining studs, replacing nuts and torquing to 16-18 ft. lbs.
24. Using tools P236 and US1006 or equivalents, install flywheel, torquing attaching bolts to 65 ft. lbs.
25. Ensure that crankshaft turns freely and that chains and connecting rods do not jam.
26. Install pistons, ensuring that flat spot of piston faces intake valve.
27. Cover crankcase openings, then install piston pin retaining circlips so that open end of circlip faces either crankshaft or piston top.
28. Using tool US1008a or equivalent, compress piston rings.
29. Install new cylinder base gasket on cylinder and carefully push cylinder onto piston until cylinder covers all piston rings.
30. Remove tool and push cylinder into its base in crankcase until it seats on sealing surface.
31. Secure cylinder in position by placing spacer bushings onto two diagonally opposed studs and tightening nuts.
32. Install remaining cylinders.