Impco HHI, Руководство по обслуживанию

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BACKFIRE
Checks Action
DEFINITION: The fuel ignites in the intake manifold, or in the exhaust system, making a loud popping
noise.
Preliminary Check None.
Ignition System Checks

Check for the proper primary ignition coil wire output voltage using the
spark tester
J26792 or the equivalent.

Check the spark plug wires by connecting an ohmmeter to the ends of
each wire in question. If the meter reads over 30,000 ohms, replace the
wires.

Check the connection at primary ignition coil wire.

Check for deteriorated spark plug wire insulation.

Check the spark plugs.
Remove the plugs and inspect them for the following conditions:

Wet plugs.

Cracks.

Wear.

Improper gap.

Burned electrodes.

Heavy deposits.
Engine Mechanical
Check
Check the engine for the following:

Improper valve timing.

Engine compression.

Manifold vacuum leaks.

Intake manifold gaskets.

Sticking or leaking valves.

Exhaust system leakage.

Check the intake and exhaust system for casting flash or other restri c-
tions.
Fuel System Checks
Perform a fuel system diagnosis. Refer to Gas Fuel System Diagnosis .