Kohler 24RCL manual 10 Spark Plug Gap Adjustment

Problem/Condition	Means of Identification	Possible Cause/Solution
Gap-bridged spark	Built-up deposits and gap between electrodes	Oil or carbon fouling. Clean and regap the spark
plug	closing.	plug.
Oil-fouled spark plug	Wet, black deposits on the insulator shell, bore,	Excessive oil entering combustion chamber
	and electrodes.	through worn rings and pistons, excessive
		clearance between valve guides and stems, or
		worn or loose bearings. Replace the spark plug.
Carbon-fouled spark	Black, dry, fluffy carbon deposits on insulator	Incorrect spark plug, weak ignition, clogged air
plug	tips, exposed shell surfaces and electrodes.	intake, overrich fuel mixture, or excessive
		no-load operation. Clean and regap the spark
		plug.
Lead-fouled spark plug	Dark gray, black, yellow, or tan deposits; or a	Caused by highly leaded fuel. Replace the spark
	glazed coating on the insulator tip.	plug.
Pre-ignition damaged	Melted electrodes and possibly blistered	Wrong type of fuel, incorrect timing or advance,
spark plug	insulator. Metallic deposits on insulator suggest	too hot a plug, burned valves, or engine
	internal engine damage.	overheating. Replace the spark plug.
Overheated spark plug	White or light gray insulator with small black or	Engine overheating, wrong type of fuel, loose
	gray/brown spots with bluish (burned)	spark plugs, too hot a plug, low fuel pressure or
	appearance on electrodes.	incorrect ignition timing. Replace the spark plug.
Worn spark plug	Severely eroded or worn electrodes.	Caused by normal wear and failure to replace
		spark plug at prescribed interval. Replace the
		spark plug.

Figure 4-9Engine Evaluation Using Spark Plug Condition

13.Use a gapping tool to gently bend the side electrode closer to or farther from the center electrode to set the correct gap. See Figure 4-10. Position the side electrode directly over the center electrode.

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Figure 4-10Spark Plug Gap Adjustment

Note: Ensure that the spark plug tubes are seated before installing the spark plugs. If the tubes were removed, reinstall them before installing the spark plugs.

14.Reinstall the spark plug. Do not bump the electrode against the cylinder head. Rotate the spark plug clockwise until you feel resistance.

15.Use a torque wrench to torque each spark plug to 18 Nm (13.3 ft. lbs.). Otherwise, hand-tighten the spark plug until you feel resistance.

16.Use a ratchet wrench to tighten an additional 1/4 turn. Do not overtighten, as doing so may strip the threads or alter the electrode gap setting.

17.Check the spark plug wire connector in the boot for accumulated dirt, grease, and other debris, and clean as necessary.

18.Firmly push the spark plug boot onto the spark plug.

19.Reconnect the generator set engine starting battery, negative (--) lead last.

20.Reconnect the power for the battery charger.

58 Section 4 Scheduled Maintenance TP-6905 6/14