Shindaiwa 81719 manual 139/150-Hour Maintenance, Inspect the Gearcase Protector, Valve Adjustment

50-Hour Maintenance (continued)

CAUTION!

The D-shaped shim washer must be positioned with its flat edge toward the shaft tube.

Gearcase

Shaft

Tube

D-shaped Shim
Washer	Flat (toward26024
Figure 23	tube)

Inspect the Gearcase Protector

The metal gearcase protector (p/n 72958- 16210) is installed to protect the gearcase flange from damage when working close to sidewalks or other abrasive surfaces, and should be routinely inspected for damage or excessive wear.

When replacing the protector, inspect to be sure that both of the protector mounting screws are firmly tightened and each screw is locked in place with a nut as shown.

Nut

	Gearcase Protector (P/N
Figure 24	72958-16210)

139/150-Hour Maintenance

Maintenance after first 139-hours, then every 150-hours thereafter.

nCombustion chamber should be decar- bonized, and the valve clearance should be adjusted. It is highly recommended that this is done by a Shindaiwa-trained service technician.

nReplace the spark plug annually: Use only NGK CMR5H or equivalent resis- tor type spark plug of the correct heat range. Set spark plug electrode gap to 0.024-0.028 inch (0.6 -0.7 mm).

NOTE:

The NGK CMR5H also meets the requirements for electro magnetic compliance (EMC).

Valve Adjustment

1.Remove cylinder cover, rocker arm cover, and set piston at TDC-compression.

CAUTION!

nPerforming a valve adjustment incor- rectly may cause hard starting and/or can damage the engine.

nIf you are unfamiliar with this engine or uncomfortable with this procedure, consult with an authorized Shindaiwa servicing dealer.

2.Loosen adjuster locknut so that the 2.5 mm Allen socket head adjustment screw can turn freely.

3.Insert feeler gauge .004” (0.10 mm) for both intake and exhaust between valve stem tip and rocker arm.

4.Turn adjustment screw (clockwise = tighter, counter-clockwise = looser) until feeler gauge is almost snug. Back off just enough to allow gauge to slip out with limited resistance.

5.While holding adjustment screw in place with Allen driver, tighten locknut with wrench.

6.Turn engine over several times, and return to TDC-compression. Recheck with proper feeler gauge to make sure clearance adjustment did not change as a result of tightening locknut. Readjust as necessary.

7.Replace rocker arm cover gasket to as- sure proper sealing and install cover.

IMPORTANT!

If new gasket is not available and/or old gasket is not damaged, old gasket may be re- used. Never use cracked or damaged gaskets!

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