4. Intake/Exhaust Restriction Test

4. INTAKE/EXHAUST RESTRICTION TEST

Purpose:
This purpose of this test is to determine if an intake air or exhaust restriction is contributing to a no start or hard start condition. If the engine starts with a high intake air or exhaust restriction, a considerable amount of black/blue smoke is produced.

Intake/Exhaust Restriction
- Inspect the air filter and inlet ducts.
- Inspect the exhaust system.
- Check for illumination of the air filter restriction indicator.







Recommended Procedure:
Inspect the air cleaner inlet and ducting to verify no blocks or collapsed ducting. Inspect the air cleaner housing and filter for correct installation. Inspect the air filter restriction gauge to make sure the indicator is in the normal operating range. Inspect the exhaust system for damaged or blocked pipes.

Air Filter Restriction Gauge:

Possible Causes:

NOTE: Reset the air filter restriction gauge after repairing a restriction concern.

- Snow or foreign material restricting the airflow at the air inlet
- Misrouted air cleaner ducting
- On engines recently repaired, rags or cap plugs may have been inadvertently left in an air inlet pipe
- Tailpipe or muffler may have collapsed or been damaged

Tools Required:
None