Table 4-2. UNIT MAINTENANCE TROUBLESHOOTING (Cont)
TEST OR INSPECTION
Check drain valve or drain plug for leak
Replace defective drain valve gasket. Replace or repair drain valve or drain plug.
Check the emergency dump valve for a leak
Replace defective dump valve gasket. Replace or repair a defective emergency dump
Check the drain valve control handle, rod and rod support assembly.
(Not applicable to Advance Model TRL 1000)
Repair or replace the drain valve control handle, rod and rod support assembly.
Check the emergency dump valve control lever and rod assembly for wear or damage.
Repair or replace the dump valve control lever and rod assembly.
Section V. UNIT MAINTENANCE PROCEDURES
a. This section contains unit maintenance procedures as authorized by the Maintenance Allocation Chart
(MAC), Appendix B of this manual.
b. The tank assembly includes the manhole cover assembly, the drain valve and control handle, the emer-
gency dump valve and control lever, and the pump port and tiedown assemblies.
c. The tank and its components must be cleaned before any repair is started. Each time a component is
removed for repair, inspection or other service, it must be cleaned thoroughly.
d. No repair will be initiated until the tank has been thoroughly
vented and cleaned. The atmosphere inside
the tank must be tested and certified safe by technically qualified
personnel prior to welding on the tank or entry
into the tank to perform maintenance.
e. Before attempting any welding repair on the tank, drill four 1/2 inch diameter drain holes in each skid
(eight holes required) and four 1 1/2 inch holes in each skid (eight holes required). (Figure 4-1)