Lincoln Electric BULLDOG SVM208-A Service Manual page 74

F-26
ENGINE THROTTLE ADJUSTMENT TEST
PROCEDURE
This test can be conducted by any of three meth-
ods.
Strobe-tach Method:
1. Stop the engine and remove the spark plug wire
to prevent accidental kickback or starting.
2. With the black or red marking pencil, place a
mark on one of the blower paddles, which can
be reached through the vent slots in the end
bracket. See Figure F.7.
3. Connect the strobe-tach according the manu-
facturer's instructions.
4. Reconnect the spark plug wire and start the
engine. Direct the strobe-tach light on the blow-
er paddle and synchronize it to the rotating
mark. The tach should read 3700 RPM.
5. Using the 10mm socket wrench, slightly loosen
the throttle locking nut. See Figure F.8.
5. Using the screwdriver adjust the high speed
stop screw until the tach reads 3700 RPM. See
Figure F.9.
5. Re-tighten the throttle locking nut. See Figure
F.8.
TROUBLESHOOTING AND REPAIR
ROBIN/SUBARU ENGINE (continued)
FIGURE F.7 – MARK LOCATION
MARK
BULLDOG® 140
Frequency Counter Method:
1. Plug the frequency counter into one of the 115
VAC auxiliary receptacles.
2. Start the engine
frequency counter. At the proper RPM (3700),
the counter should read 62 Hz.
3. Using the 10mm socket wrench, slightly loosen
the throttle locking nut. See Figure F.8.
4. Using the screwdriver, adjust the high speed
stop screw until the frequency counter reads
3700 RPM. See Figure F.9.
5. Re-tighten the throttle locking nut. See Figure
F.8.
Oscilloscope Method:
1. Connect the oscilloscope according to the man-
ufacturer's instructions.
waveform should exhibit a period of 16.2 mil-
liseconds. Refer to the NORMAL OPEN
CIRCUIT VOLTAGE WAVEFORM (115 VAC
SUPPLY) HIGH IDLE - NO LOAD in this section
of the manual.
F-26
and check the
At 3700 RPM, the