Impco HHI, Руководство по обслуживанию

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CUTS OUT, MISSES
Checks Action
DEFINITION : A surging or jerking that follows engine speed, usually more pronounced as the engine load
increases, but normally felt below 1500 RPM. The exhaust has a steady spitting sound at idle, low speed,
or hard acceleration for the fuel starvation that can cause the engine to cut-out.
Preliminary Checks None.
Ignition System Checks

Start the engine.

Check for proper ignition output voltage with spark tester J 26792.

Verify that the spark plugs are the correct type and properly gapped

Check for a cylinder mis fire.
Remove the spark plugs in these cylinders and check for the following condi-
tions:

Insulation cracks.

Wear.

Improper gap.

Burned electrodes.

Heavy deposits.
Visually/Physically inspect the secondary ignition for the following:

Ignition wires for arcing and proper routing.

Cross- firing .

Primary ignition coil wires for cracks or carbon tracking.
Engine Mechanical
Checks

Perform a cylinder compression check.
Check the engine for the following:

Improper valve timing.

Worn rocker arms.

Worn camshaft lobes.

Broken or weak valve springs.

Check the intake and exhaust manifold passages for casting flash.
Fuel System Checks
Check the fuel system:

Check the in-line fuel filter for restrictions.

Low fuel pressure, etc. Refer to Gas Fuel System Diagnosis .
Additional Check

Check for Electromagnetic Interference (EMI), which may cause a missing
condition.

Using a scan tool, monitor the engine RPM and note sudden increases in
rpms is displayed on the scan tool but with little change in the actual en-
gine RPM. If this condition exists, EMI may be present.

Check the routing of the secondary wires and the ground circuit.