Shindaiwa 6850-9430, GP3410 manual Maintenance continued, 139/150-HourMaintenance, Valve Adjustment

Maintenance (continued)

139/150-Hour Maintenance

Maintenance after first 139-hours,	. Replace the spark plug annually: Use
then every 150-hours thereafter.	only NGK CMR5H or equivalent resis-
. Combustion chamber should be decar-	tor type spark plug of the correct heat
	range. Set spark plug electrode gap to
bonized, and the valve clearance should
	0.024-0.028 inch (0.6 -0.7 mm).
be adjusted. It is highly recommended
that this is done by a Shindaiwa-trained
service technician.

NOTE:

The NGK CMR5H also meets the requirements for electro magnetic com- pliance (EMC).

Valve Adjustment

CAUTION!

Performing a valve adjustment incorrectly may cause hard start- ing and/or can damage the engine. If you are unfamiliar with this engine or uncomfortable with this proce- dure, consult with an authorized Shindaiwa servicing dealer.

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

. Loosen adjuster locknut so that the

2.5mm Allen socket head adjustment screw can turn freely.

Figure 16

Figure 17

3.Insert .004" (0.10 mm) feeler gauge 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.

Figure 18

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. Re-adjust as necessary.

7.Replace rocker arm cover gasket to assure proper sealing and install cover.

IMPORTANT!

If a new gasket is not available and/or the old gasket is not damaged, the old gas- ket may be reused. Never use cracked or damaged gaskets!

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