Chart B1 - Restricted Exhaust System Checks

NOTE: Proper diagnosis of restricted exhaust system is essential before any components are replaced.

Remove the rubber hose from the exhaust manifold AIR pipe check valve.
Connect fuel pump pressure gauge to hose and nipple from Propane Enrichment Device (J26911).
Insert nipple into exhaust manifold AIR pipe.
With engine at normal operating temperature and running at 2500 RPM, observe exhaust system backpressure on gauge.
If backpressure exceeds 2 3/4 psi, a restricted exhaust system is indicated.
Inspect entire system for collapsed pipe, heat stress or possible internal muffler failure.
If there is no obvious reasons for excessive backpressure, a restricted catalytic converter should be suspected and replaced.