Mack LEU, Operator'S Handbook Manual

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MAINTENANCE AND LUBRICATION 27
MAINTENANCE INTRODUCTION
This handbook contains maintenance information specific to the Natural Gas Vehicle
and Engine. For recommended lubrication change intervals and procedures for
gear oils (transmission, rear axle carrier[s], front drive axle carrier, transfer case
and flywheel PTO) or other maintenance schedules or procedures not included in
this portion of the handbook, refer to the
Maintenance and Lubrication Manual
(21394653) or your vehicle model’s Operator Handbook.
DAILY LNG/CNG FUEL SYSTEM CHECKS
Check for Methane Leaks or Loss of Vacuum
The LNG and CNG fuel systems are pressurized systems. Any damage to the fuel
delivery system may result in leaks. All the tubing carrying liquid or gas fuel from
the fuel tanks to the vaporizer are stainless steel. The tubing from the vaporizer
throughout the remainder of the fuel delivery system is specialized high pressure
tubing. Any damage to this system should be repaired as soon as possible.
During the daily walk around, check for any leaks or damage to the fuel system. The
appearance of a vapor cloud accompanied by a hissing noise may indicate a methane
leak. Inspect the outside of the fuel tank for frost (LNG only). A frosted tank indicates
that the inner tank is leaking into the outer tank or there has been a loss of vacuum.
Open the tank door; if the Evacuation Plug has popped out, the tank must be serviced.
A leaking condition requires service before the vehicle is operated.
WARNING
Do not operate a vehicle which has a
methane leak.
Note: Some frosting and sweating is normal around the plumbing fittings in the
shrouded end of the tank.