TM-9-2320-280-34 HMMWV Direct Support & General Support Maintenance Manual Download

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TM 9-2320-280-34 14-12. AMBULANCE HEATER FUEL CONTROL VALVE TESTING AND ADJUSTMENT MODEL 10530A) (Cont'd) 13. Fill graduated beaker (1) with fuel to 50 cubic centimeter level. Close fuel container shutoff valve (7) and open graduated beaker shutoff valve (6). Allow heater to operate for thirty seconds. 14. Check fuel consumption rate at graduated beaker (1) for exactly one minute. Fuel consumption rate should be 10-13 cc per minute. If fuel consumption rate is not 10-13 cc per minute, adjust fuel control valve (11) by turning screw (10) clockwise to increase flow or counterclockwise to decrease flow. If not adjustable, replace fuel control valve (11) (para. 14-10). 15. Place HI-LO switch (5) in HI position. 16. Observe exhaust outlet (13) for smoke. Visible smoke up to three minutes after switch (5) is positioned to HI is normal. If smoke continues to be visible at exhaust outlet (13) after three minutes, repair heater assembly (para. 14-10). 17. Fill graduated beaker (1) with fuel. Check fuel consumption rate at graduated beaker (1) for exactly one minute. Fuel consumption rate should be 19-23 cc per minute. If fuel consumption rate is not 19-23 cc per minute, replace fuel control valve (para. 14-10). 18. Close graduated beaker shutoff valve (6) and open fuel container shutoff valve (7). 19. Check operating amperage on ammeter (2). If operating amperage exceeds 10 amperes, repair heater assembly (para. 14-10). NOTE Purge time is the interval from turning toggle switch to OFF position until indicator lamp goes out. 20. Place toggle switch (3) to OFF position and record purge time. Purge time should not exceed four minutes. If purge time exceeds four minutes, replace or adjust flame detector switch (para. 14-10). 21. Start heater and allow to operate for thirty seconds. 22. Partially restrict fresh air inlet (12) with a sheet or cardboard or sheet metal. Overheat switch on heater should actuate and shut down heater in less than five minutes. If heater does not shut down after five minutes, replace overheat switch (para. 14-10). Make sure indicator lamp (4) extinguishes. 23. Disconnect test equipment from heater assembly. 24. Install guard (8) on housing (14) with two dzus fasteners (9). 14-74