GT55/GT60 Front Crankshaft Ball Bearing - OS29730000 by O.S. Engine  [OS29730000]

Front crankshaft bearing for GT55 and GT60 engines

This replacement part fits the front crankshaft position on compatible O.S. engine models listed in the product title. It supports the crankshaft spindle, reduces front-end friction, and helps preserve smooth rotation during normal operation.

Fitment applies only to the GT55 and GT60 models shown in the product name, so verify your engine code before purchase. Installation is a press-fit at the crankshaft front plate; use a soft-faced driver or a bearing press to avoid damaging the crankcase or bearing race. Remove the carburetor and cooling head as necessary to reach the crankshaft for replacement.

When diagnosing idle or throttle issues, check the bearing for roughness, axial play, or excess endfloat since a worn front bearing can cause vibration that upsets idle stability and throttle response. After fitting, confirm free rotation by hand before reassembly, then perform a short low-throttle run to ensure correct seating.