TOMCAR TM2, Owner'S Manual

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MAINTENANCE & LUBRICATION
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Spark Plugs
Spark Plugs
CAUTION
Using non-recommended spark plugs can result in serious engine damage. Always use TOMCAR
®
recommended spark plugs. Refer to the
Specifications section (pgs. 101-102) for details.
Spark plug condition is indicative of engine operation. The spark plug firing end condition should be read after the engine is warmed up and the
vehicle is driven at higher speeds. Immediately check the spark plug for correct color.
The spark plug gap recommendation is 0.09 cm.
Spark Plug Diagnosis
1. The normal insulator tip is gray, tan or light brown. There will be few combustion deposits. The electrodes are not burned or eroded.
This indicates the proper type and heat range for the engine and the service. The tip should not be white. A white insulator tip indicates
overheating, caused by the use of an improper spark plug or incorrect carburetion adjustments.
2. The wet fouled insulator tip is black. A damp oil film covers the firing end. There may be a carbon layer over the entire nose.
Generally, the electrodes are not worn. General causes of fouling are excessive oil or incorrect fueling.
A hot exhaust system and engine can cause serious burns. Wear protective gloves when removing a spark plug for inspection.
Spark Plug Removal and Replacement
1. Lift cargo box to access the engine compartment.
2. Remove the spark plug cap. Clean spark plug area carefully before removal, as dirt might fall into the engine during removal.
Remove the plug by rotating it in a counterclockwise direction.
3. Reverse the procedure for spark plug installation.
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