EXPLANATION OF
REQUIRED EMISSION CONTROL
MAINTENANCE SERVICES
The following explanation of required emission control maintenance items and service intervals has been keyed by number
to corresponding line numbers in the preceding maintenance chart.
More frequent maintenance will be required where an engine is operated under other than normal conditions (e.g., heavy
dust, excessive idle.)
1
.FUEL FILTERS. Replace elements in the strainer and the filter every 10,000 miles, or when plugging is indicated.
2
.INJECTORS. Check injector timing (proper height adjustment between injector follower and body is primary to
emission control). The injector timing should be set with the appropriate tool depending on the injector size.
Injector timing should be checked, and adjusted if necessary, every 40,000 miles on vehicles used in city,service
or every 80,000 miles on vehicles used in other applications.
3.
GOVERNOR. Check the engine idle speed and no-load speed every 40,000 miles and adjust as necessary. An
idle speed lower than recommended will cause the engine to be accelerated from a speed lower than the speed
at which the engine was certified. A no-load speed higher than recommended will result in a full load speed
higher than rated, and higher than the speed at which the engine was certified.
4.
THROTTLE DELAY. This system limits the amount of fuel that can be injected during acceleration by limiting the
rate of injector rack movement with a hydraulic cylinder. The initial location of this cylinder must be set with the
proper gage in order to achieve the appropriate time delay. Inspect every 80,000 miles.
64