TM 5-4520-241-14
Table 4-2. Organizational Maintenance Troubleshooting - Continued
MALFUNCTION
TESTING OR INSPECTION
CORRECTIVE ACTION
4 - Continued
Step 15. Check for fuel in float bowl. Remove pipe plug (1, fig. 4-6) from side of float bowl. Using small wire
or pencil tip, gently tap float. It must bounce up and down to show that fuel is present in bowl. If
float bounces, proceed to step 16. If float does not bounce, inspect screen and needle.
Disconnect fuel line from elbow (2, fig. 4-6). Unscrew elbow and pull out screen (3). Clean or
replace screen. If it is clean, inspect needle and seat. Remove screws (5) and washers (6). Pull
off cover (7) and gasket (8). Remove pin (9) and pull off float (10) and needle (11). If needle or
seat (12) is damaged, replace needle, seat, and washer (13) as an assembly. Reassemble in
reverse order of removal.
Step 16. Check for fuel suction. Disconnect solenoid power lead at electrical connector. Use a pencil to
mark the position of the fuel needle in the carburetor body. Carefully unscrew and remove fuel
needle (1, fig. 4-7), counting the number of turns until needle is free. Connect power plug. Turn on
heater and feel for vacuum at the fuel needle hole in the carburetor body. You should feel a
vacuum if you place your finger over the hole. If there is a vacuum, check per step 17. If there is
no vacuum, clean fuel jet and mixer.
Do not reinstall fuel needle.
Disconnect fuel lines and wires from carburetor. Remove screws (3, fig. 4-7) and washers (4)
securing assembled carburetor to burner head. Pull off carburetor.
Pull off preformed packing (6) and clean fuel mixer (5) with a wire brush. Unscrew mixer and
remove to expose fuel jet (7). Using a piece of bare 20-gage or 22-gage wire, clean out bole in
fuel jet. Do not remove jet from carburetor. Insert wire into end of jet. It should pass through to
hole for fuel needle. Reinstall fuel mixer and preformed packing. Reinstall carburetor on burner
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