AIR-FUEL RATIO CONTROL MAINTENANCE - CONTINUED
FUEL RATIO CONTROL AND GOVERNOR CHECK - CONTINUED
If dynamic fuel ratio control setting is within +0.010 in. (0.25 mm) of specification given on engine informa-
tion plate, an adjustment is not necessary.
For adjustment of control, refer to Fuel Ratio Control Adjustment in this work package.
Check boost pressure that gives full torque rack travel, as follows:
Connect pressure gage, pressure regulator and air supply to fitting (40).
Apply 4 psi (25 kPa) air pressure to fuel ratio control.
Start engine (TM 5-3805-248-10). Run engine at 900 RPM and rapidly move governor control shaft to full FUEL
ON position. Record maximum indicator reading.
Repeat this procedure several times. Each time increase air pressure 7 psi (5 kPa).
Record first air pressure setting that gives full torque fuel setting. Full torque fuel setting was measured in step 13.
This is boost pressure that moves fuel ratio control out of rack control position. This pressure permits dynamic full
torque fuel setting. If pressure recorded is less than rated boost, fuel ratio control cannot be a cause of low power
FUEL RATIO CONTROL ADJUSTMENT
Before governor seals are cut or removed, refer to Fuel Ratio Control and Governor Check in this work
package to make sure an adjustment is needed.
Refer to engine information plate for correct dynamic fuel ratio control setting specification before an adjustment is
Install and zero fuel injection tool kit. Refer to Fuel Ratio Control and Governor Check in this work package for proce-
Remove air line (39) cover (42) and gasket (41) from engine.