TM 5-4310-385-13
CHAPTER 4. INTERMEDIATE DIRECT SUPPORT
MAINTENANCE INSTRUCTIONS
SECTION I. TROUBLESHOOTING
4-1. GENERAL. This section contains troubleshooting procedures to be performed by direct support maintenance. This
assumes that troubleshooting and maintenance procedures have already been performed at the organizational level for
similar malfunctions. information should be reviewed in Chapter 3: Unit Maintenance Instructions; Section V.
Troubleshooting; and Section VI. Organizational Maintenance Procedures.
4-2. COMPRESSOR UNIT. Direct support troubleshooting and maintenance procedures cover cylinder and crankcase
component replacement: cylinder block, pistons, connecting rod assemblies, crankshaft and oil seals.
4-3. ELECTRIC MOTOR. Direct support troubleshooting and maintenance procedures cover motor component
replacement.
4-4. TROUBLESHOOTING TABLE. The following columns are used in the Troubleshooting Table.
a.
Malfunctions. Malfunctions listed are the ones most likely to happen. Not all possible malfunctions can be
foreseen and listed.
b.
Test or inspection. Tests or inspections are listed to help you find the cause of the malfunction. The tests that
are easiest to do are listed first. The tests that are hardest to do are listed last.
c.
Corrective Action. Corrective actions are listed to help eliminate the malfunction. The paragraph number of the
detailed maintenance procedure is given in parentheses.
Table 4-1. Troubleshooting
Malfunction
Test or Inspection
Corrective Action
COMPRESSOR
1. COMPRESSOR DOES NOT PUT OUT ENOUGH AIR.
Step 1.
Check for leaking gaskets between cylinder heads and cylinders, and gaskets between cylinders
and crankcase.
Install new gaskets (paragraph 4-7).
Step 2.
Check for worn or damaged intake or exhaust valves in low pressure cylinder.
Replace as necessary.
2. EXCESSIVE OIL CONSUMPTION.
Step 1.
Check for worn or stuck piston rings, particularly oil ring.
Install new piston rings (paragraph 4-7).
Step 2.
Check for leaking gasket between cylinder and crankcase, leaking gaskets between
crankcase and crankcase cover, or leaking gasket between crankcase cover and breather
assembly cover.
Install new gaskets (paragraph 4-7).
Step 3.
If oil leakage occurs between crankcase cover and breather assembly cover, check felt oil separator
on breather assembly.
Replace oil separator (paragraph 4-7).
4-1
