Makita EK7650H, EK7651H Ignition system, Tightening torque specifications, Checking Spark Plug

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Repair

[4]DISASSEMBLY/ASSEMBLY

[4]-9. Ignition system (cont.)

CHECKING SPARK PLUG

WARNING !!

•When a spark is produced, high-voltage current is delivered from Ignition coil to Spark plug. It is, therefore, very dangerous to pull Recoil starter knob with your hand on Ignition cable. Be sure to keep your hands off from Ignition cable when checking for spark.

•Fuel is extremely flammable and fuel vapors are explosive. Therefore, clean up spilled fuel before starting to check for spark. Also, be careful not to do the check near Carburetor.

(1) Remove Plug cap from Spark plug, then Spark plug from Cylinder head complete with the supplied socket wrench. Note: If the electrodes of Spark plug are wet, wipe them with a rag then dry them with an air blower.

(2) Using a wire brush, carefully clean up carbon deposits (if any) from the electrodes and the ceramic insulator around

	the center electrode.
(3) Adjust the electrode gap to 0.5mm by carefully bending the side electrode. Fig. 42
	Use Feeler gauge set (1R366) to check the gap width:
	between the center electrode and the side electrode, insert 0.5mm leaf					side electrode
	of Feeler gauge set. (Fig. 42)
(4) Install another Spark plug into spark plug hole to prevent air/fuel mixture
	from leaking outside of engine.							Electrode gap
(5) Connect the removed Spark plug with Plug cap, then ground the threads								must be 0.5mm.
	of Spark plug to a proper metal part of the engine.
(6) With Stop switch on, pull Recoil starter knob gently and check for spark.							center electrode
	Note: It is hard to see the spark in a bright location.
	Therefore, be sure to do the check in a shady but well-ventilated place.
(7) If spark is not produced, replace Spark plug with a new one,
	then check for spark by following the procedure (1) to (6) once again.
[5] Tightening torque specifications
		Application							Tightening
		(for fastening A to B)			Fastener
									torque (N.m)
		A	B
1		Cushion	Tank complete	M6x30 Hexalobular socket head bolt					7
2		Cutting arm	Cylinder block complete	M6x25 Hexalobular socket head bolt
3		Cutting arm	Belt cover		M8 Hex nut				30
4		Front inner holder		M6x30 Hexalobular socket head bolt					3
5		Crank case	Cylinder block	M6x30 Hexalobular socket head bolt					12
6		Cylinder head complete	Cylinder block	M6x35 Hexalobular socket head bolt					12
7		Flywheel	Crankshaft		M10 Flange nut				40
8		Clutch holder	Crankshaft	Hexagonal portion (M16-24) of Clutch holder					38
9		Clutch assembly	Crankshaft	M10-17 Hex lock nut					18
10		Rocker arm	M5 Hex socket head bolt		M5x9 Hex nut				6