ENGINE REPAIR
CRANKSHAFT ASSEMBLY REPAIR

1. To repair the crankshaft requires special tools, including a press with a minimum capacity of 15 tons, a fixture for pressing apart the flywheels, an alignment jig for pressing them together again, and a set of machinist's centers fitted with two dial indicators to check for alignment after crankshaft reassembly.  If you don't have these tools and the ability to use them
properly, take your crankshaft to an Ossa dealer for repairs.
2. The crankshaft needs repairs when:

a. The connecting rod is damaged.
b. The flywheels are not aligned within given tolerances.
c. Either flywheel is damaged.
d. The connecting rod, crank pin, and bearing are worn or damaged.
e. The connecting rod's small end hole is worn or damaged.
3. Mount the crankshaft in a set of machinist's centers (see Figure 1).  There should be no more than .001" runout of the flywheels, measured at the point where the main bearings mount on either side of the crankshaft.
4. If there is more, or if the crankshaft is misaligned, the complete assembly must be inspected and repaired.
5. If there is any roughness in the big end rod bearing, or any perceptible up and down play in the connecting rod, replace the big end bearing as an assembly, including a new connecting rod, crank pin, rollers, and roller cage.

This is necessary because the rod is the outer bearing race and the crank pin is the inner bearing race, and to replace one without replacing both is a waste of time and money.  The life expectancy of such a bearing assembly would be extremely short.

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