Briggs & Stratton 271172 Main Bearings, Cleaning Cylinder, Check Bearings, Check Plain Bearings

Cleaning Cylinder

1.Wash the cylinder thoroughly in a solvent such as kerosene or other commercial solvent.

2.Wash cylinder again using a stiff brush with soap and hot water.

3.Rinse cylinder thoroughly with hot running water.

4.Repeat washing and rinsing until all traces of honing grit are gone.

NOTE: Honing grit is highly abrasive and will cause rapid wear to all of the internal components of the engine.

When cylinder and crankcase have been thoroughly cleaned, use a clean white rag to wipe the cylinder bore. If honing grit is still present, it will appear as a grey residue on the rag. Re-wash and rinse entire cylinder then check again. When there is no trace of honing grit on the rag, the cylinder is properly cleaned. Oil the cylinder bore to prevent rusting.

MAIN BEARINGS

Check Bearings

Briggs & Stratton OHV engines are equipped with plain bearings machined into the cylinder or cover/sump, DU™ bearings, or ball bearings to support the crankshaft.

Check Plain Bearings

Machined bearings are not repairable. If a machined bearing is scored or worn, the cylinder or cover/sump must be replaced.

Check DU™ Bearings

Main bearings should be replaced if scored or if plug gauge (A, Figure 4) will enter bearing. Try gauge at several locations in bearing.

Check Ball Bearings

Ball bearings must rotate freely. If any rough spots are felt, the ball bearing must be replaced (Figure 5).

NOTE: DO NOT reuse ball bearings. The bearing races are usually damaged during removal.

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Figure 5

NOTE: Standard and reject sizes for the main bearings are shown in Section 12 - Engine Specifications.

Check Camshaft Bearings

The camshaft is supported by machined

bearings which are not serviceable. Check

Figure 4camshaft bearings with Plug Gauge #19164. If gauge can be inserted 1/4” (6.4 mm) or more,

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