Table 2-1. Direct Support Troubleshooting Guide (Continued)
TEST OR INSPECTION
Step 5. Step through the air lines starting at the air compressor and disconnect them one at a time until the
source of the air leak or plugging is found.
Repair as necessary. Replace the air compressor if the above steps have not isolated the problem and
send it to General Support Maintenance for repair (para. 2-72).
8. Air compressor runs but does not reach 1700-1800 psig.
Follow the steps of air compressor runs but pressure does not build up, except for replacement of the air
compressor. (Malfunction 7)
Check the third stage valves.
(a) Replace inlet and outlet valves on the third stage (para. 2-72).
(b) Replace the air compressor and send to General Support Maintenance (para. 2-72).
9. Air compressor has low output.
Step 1. Check inlet air filter on air compressor.
Replace if dirty (para. 2-72).
Step 2. Refer to other air compressor pressure problems and check that there are no air system leaks.
Repair as necessary.
Step 3. Check air compressor first stage valves for wear/corrosion.
(a) Replace inlet and outlet valves (para. 2-72).
(b) Replace air compressor (para. 2-72) and send to general support for piston and ring wear
problems, probably in the third stage cylinder.
1. Air system pressure cannot be adjusted down to 85 psig.
Check air pressure regulator adjustment.
Replace air pressure regulator (para. 2-61).
2. Air system pressure less than 80 psig and cannot be adjusted upwards.
Problem typically associated with high air consumption. Shut the ROWPU down. Shut the air manifold block
valves off one at a time until air pressure climbs.
(a) If closing a specific valve causes air pressure to rise, troubleshoot that device for leakage.
(b) If no leaks are found, replace the air regulator (para. 2-61).
3. Outlet air filter base leaks air.
(a) If the top cap or the filter cylinder leaks at the base, replace the preformed packings (para. 2-59).
(b) If the relief valve on the filter top leaks, replace the top and relief valve assembly (para. 2-59).
(c) If the base leaks at the tube fittings, repair by removing the leaking fitting and replace it (para.
(d) If the base leaks, replace the filter assembly (para. 2-59).
(e) If air comes out from underneath the base, replace the air filter cartridge (para. 2-59).
4. Outlet air filter suspected of bypassing water or oil.
Turn the air compressor off and close the air storage tank valve. Relieve the air system pressure by opening a drain
valve on either air manifold. Remove the air filter outlet check valve, Install a new air filter in the filter chamber and
start the air compressor. Run the air compressor for ten minutes and check if water is being blown out of the filter
If water is being blown out, the filter is bypassing. Replace the outlet air filter assembly (para. 2-59).