Craftsman 143.991200 Specifications download pdf (Page 60)

IGNITION TIMING CHECK

In order for an engine to run effectively and efficiently,

the spark must ignite the compressed air-fuel mixture

when the piston is in a specific position to deliver

maximum power. This position is known as Before

Top Dead Center (BTDC). If the mixture is ignited too

soon, kickback can be experienced due to preignition.

If the mixture is ignited too late, loss of power can be

experienced due to retarded spark. A partially sheared

or the wrong flywheel key can cause kickback, loss

of power, or an inability to start the engine with a good

spark. Check the flywheel key if one of these

symptoms exist. See Chapter 9 under "Service" for

the disassembly procedure.

Timing on a solid state module is not adjustable. The

air gap check consists of having the proper .0125"

(.3175 mm) air gap gauge, part # 670297 between

the flywheel magnets and the laminations of the

module while tightening the mounting screws to the

proper torque. Remove the air gap gauge and rotate

the flywheel to check for any possible striking points.

If none are found, the air gap is set correctly and the

air gap check is completed (diag. 7).

SERVICE TIPS

DO NOT:

Interchange flywheels, flywheel keys, or spark plugs.

Use flywheels with cooling fins that are broken off.

Use a standard business card as an air gap gauge.

Attempt to reglue the spark plug lead back into a solid state module.

Store a solid state module within 20 feet (6.1 meters) of an unshielded welder.

.0125"

(.3175 mm)

Main Menu

1 2 ... 55 56 57 58 59 60 61 62 63 64 65 ... 93 94

No comments

Craftsman 143.991200 Specifications Page 60