O.S. Engine Crankshaft Ball Bearing OS23930000 for R 21RX, 21XM  [OS23930000]

O.S. ENGINES CRANKSHAFT BALL BEARING R 21RX,21XM
Price:
£14.40
Brand:
O.S. Engine
Model:
OS23930000
GTIN:
4531028109209
Condition:
Brand New
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Engine crankshaft bearing overview

This crankshaft ball bearing is supplied as a replacement accessory for O.S. Engine R 21RX and 21XM engines referenced in the product name. It provides support for crank rotation, reduces friction, and maintains alignment during engine operation.

Before installation: inspect the crankcase bearing seat for damage or foreign matter, use a correct bearing driver or press to install the part evenly, and verify endplay and free rotation after fitting. For maintenance, monitor bearing smoothness and replace when any roughness, play, or overheating is present.

Specifications

  • Item: Crankshaft Ball Bearing R 21RX, 21XM
  • Material: Not specified
  • Model Number: OS23930000
  • Compatibility: R 21RX, 21XM

A focused replacement for rebuilds and routine upkeep, this bearing helps restore correct fit and crank alignment to recover engine performance.

Does this bearing match original dimensions for R 21RX/21XM?

The listing specifies compatibility with R 21RX and 21XM; always confirm the bearing seats and clearances on your engine before final assembly to ensure the correct fit.

Will this fit without machining the crankcase?

Most installations only require a clean, undamaged seat; if the seat is worn or out of spec, machining or repair may be necessary to achieve a proper press fit.

Are there indicators it is the wrong size?

If the bearing does not sit flush, requires excessive force, or allows unusual endplay, these are signs of a fitment issue that should be addressed before running the engine.

Who should I consult if fitment is unclear?

Refer to your engine service manual or contact an experienced model engine mechanic for guidance on measuring and correcting bearing seats and clearances.

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