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Schoolcraft Power Train Engineering Services

We start with extensive preparatory machining of the engine block to install splayed main caps from Kennedy Diesel. These caps relocate the outer bolts of the center three main caps (see photo at left). The bolt stress is now distributed into the block rail rather than in the undercut web area to eliminate a common web cracking failure mode through the outer bolt holes.

After align bore and align hone, a Block True fixture is used to machine the deck surfaces. This ensures that the decks are perpendicular to each other and 45° from a line passing through the crank and cam centerlines. The final deck height is established in conjunction with the rod length to set the piston protrusion to the desired level (see photo at left). The block is then bored and torque-plate honed to the optimum piston-to-bore clearance.

The crank shaft is ground to ensure perfectly aligned main journals and perfectly indexed rod journals. This usually can be accomplished with only 0.010” undersize journals resulting. The crankshaft and reciprocating hardware is then balanced to within 0.02 oz-in per plane (see photo at left).

The connecting rods are reconditioned and machined to equalize their lengths.