91SZ-H Crankcase Cover Plate - O.S. Engine OS29067010  [OS29067010]

91SZ-H Cover Replacement

This cover plate, sold as O.S. Engine OS29067010, is a machined replacement intended for crankcases using the 91SZ-H designation. It restores the crankcase enclosure when the original plate is removed for service.

For installation, remove existing mounting screws, clean the mating surfaces, seat the new plate and torque bolts in stages to keep the crankcase aligned. The component supports standard maintenance tasks like seal replacement and bearing checks.

In tuning scenarios the plate preserves crankcase geometry, which helps sustain consistent compression and engine response during bench runs. Treat this as a service part, not a performance modifier.