TM 9-4940-549-14&P
Table 4-2. Troubleshooting-Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
6.
Abnormal Fluctuations of Dynamotor-Welder Output Current.
Check for dirty rheostat contact.
Step 1.
Clean contact.
Disassemble welder to check brush tension.
Step 2.
Adjust brush tension or replace brushes (para. 13-4).
AIR C O M P R E S S O R
Compressor Pumping Oil.
1.
Check cylinders or piston for wear, scratches, or scoring.
Step 1.
Replace defective cylinder or piston (para. 1411).
Check for piston rings broken or not seated in.
Step 2.
Replace piston rings (para. 14-11).
2.
Knocks or Rattles.
Check for carbon on top of piston.
Step 1.
Clean as necessary (para. 14-11).
Step 2.
Check for loose, broken, or carbonized air finger valves.
Replace defective finger valves (para. 14-11).
Check for worn or scored connecting rod, piston pin, or crank
Step 3.
pin bushings.
Replace defective parts (para. 14-11).
3.
Air Delivery Dropping.
Step 1.
Check for leaking, broken, carbonized, or loose finger valves.
Tighten or clean leaking or carbonized valves (para. 14-11). Re-
place defective valves (para. 14-11).
Check for scratched, worn or scored cylinders or pistons.
Step 2.
Replace damaged piston rings (para. 14-11).
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