to Section TOC
to Master TOC
TROUBLESHOOTING & REPAIR
ENGINE THROTTLE ADJUSTMENT TEST (continued)
Return
Return to Section TOC
Return to Section TOC
Return
Return to Master TOC
Return to Master TOC
6.If either of the readings is incorrect, adjust the throttle as follows:
Adjust HIGH IDLE: Use the 10mm wrench to loosen the locking nut. See Figure F.11 for location of the adjusting screw and locking nut. Turn the threaded screw
Adjust LOW IDLE: First make sure there is no load on the machine. Set the IDLE switch to AUTO and wait for the engine to change to low idle speed. Use the 7/16" wrench to loosen the solenoid lever arm locking nut. See Figure F.12. Adjust the collar, to change the amount of throw in the lever arm, until the tach reads between 1325 and 1400 RPM. Retighten the locking nut.
Frequency Counter Method
1.Plug the frequency counter into one of the 115 VAC auxiliary receptacles.
2.Start the engine and check the frequency counter. At HIGH IDLE (1900 RPM), the counter should read 63 Hz. At LOW IDLE (1400 RPM), the counter should read 47 Hz. Note that these are median measurements; hertz readings may vary slightly above or below.
3.If either of the readings is incorrect, adjust the throttle as follows:
Adjust HIGH IDLE: Use the 10mm wrench to loosen the locking nut. See Figure F.11 for location of the adjusting screw and lock- ing nut. Turn the threaded screw counter- clockwise to increase the HIGH IDLE speed. Adjust the speed until the frequency reads 63 Hz. Retighten the locking nut.
Adjust LOW IDLE: First make sure there is no load on the machine. Set the IDLE switch to AUTO and wait for the engine to change to low idle speed. Use the 7/16" wrench to loosen the solenoid lever arm locking nut. See Figure F.12. Adjust the collar, to change the amount of throw in the lever arm, until the frequency reads 47 Hz. Retighten the locking nut.
Oscilloscope Method
1.Connect the oscilloscope to the 115 VAC receptacle, according to the manufacturer’s instructions. At HIGH IDLE (1900 RPM), the waveform should exhibit a period of 15.8 milliseconds. At 1400 RPM, the waveform should exhibit a period of 21.4 milliseconds. Refer to the NORMAL OPEN CIRCUIT
VOLTAGE WAVEFORM (115 VAC AUXIL- IARY) HIGH IDLE - NO LOAD in this sec- tion of the manual.
2.If either waveform periods is incorrect, adjust the throttle as follows:
Adjust HIGH IDLE: Use the 10mm wrench to loosen the locking nut. See Figure F.11 for location of the adjusting screw and lock- ing nut. Turn the threaded screw counter- clockwise to increase the HIGH IDLE speed. Adjust the speed until the period is 15.8 mil- liseconds. Retighten the locking nut.
Adjust LOW IDLE: First make sure there is no load on the machine. Set the IDLE switch to AUTO and wait for the engine to change to low idle speed. Use the 7/16" wrench to loosen the solenoid lever arm locking nut. See Figure F.12. Adjust the collar, to change the amount of throw in the lever arm, until the period is 21.4 millisec- onds. Retighten the locking nut.
Return to Section TOC
Return to Master TOC
