Lincoln Electric VANTAGE 400 Service Manual page 80

F-32
ENGINE THROTTLE ADJUSTMENT TEST (CONTINUED)
Vibratach Method
A Vibratach is used to measure the vibrations
caused by the running engine. It can be positioned
anywhere where the engine vibration is reasonably
strong. The best results will likely be obtained by
opening the top engine cover and placing the
Vibratach directly against the top of the engine.
Read and understand the manufacturer's instruc-
tions for the Vibratach.
1. Start the engine and place the idle switch in the
"HIGH IDLE" position. Make sure that there is
no load on the machine.
2. Position and adjust the Vibratach; it should
read between 1860 and 1890 RPM.
3. Move the idle switch to the "AUTO IDLE" posi-
tion and wait for the idle solenoid to energize,
and the engine RPM to drop and stabilize at
the low idle RPM.
4. Position and adjust the Vibratach; it should
read between 1300 and 1400 RPM.
If either of the readings is incorrect, proceed to
the "THROTTLE ADJUSTMENT PROCE-
DURE".
THROTTLE ADJUSTMENT PROCEDURE
IMPORTANT: Both the high and low idle settings
are adjusted at the solenoid.
1. Check that the linkage attaching the solenoid
to the engine speed control lever is properly
aligned and in good condition.
important that the solenoid linkage be more
precisely aligned when in the high speed (de-
energized position).
2. Check to be sure the spring located inside the
rubber boot is not broken or missing. In the
default, (de-energized) position the spring
should be holding the solenoid in the high
speed position. See Figure F.5.
TROUBLESHOOTING & REPAIR
It is more
VANTAGE® 400
NOTE: Low idle RPM must be set, and the
adjustment nuts tightened, before the high idle
RPM is adjusted.
Low Idle adjustment:
1. With engine running and no load applied to the
machine, place the idle switch in the "AUTO
IDLE" position. Wait for the idle solenoid to
energize and the engine speed to drop and
stabilize to low idle RPM.
2. If the low idle RPM requires adjustment, loosen
the low idle adjustment jam nuts. Turn both
nuts so they are clear of the swivel fitting.
Rotate the swivel fitting until the engine speed
has been set to between 1200 and 1400 RPM.
Hold the swivel fitting in position while tighten-
ing the first jam nut against the swivel fitting,
and then tighten the second jam nut against
the first. Do not adjust at engine stop lever.
3. Re-check the low idle RPM, and then proceed
to the high idle adjustment.
High idle adjustment:
1. With engine running, place the idle switch in
the "HIGH IDLE" position. The solenoid should
immediately de-energize, allowing the engine
to increase to high idle speed.
2. If the high idle RPM requires adjustment,
loosen the high idle adjustment screw jam at
engine lever + high speed stop nut and turn the
adjusting screw until the engine speed is
between 1860 and 1890 RPM.
adjusting screw in position while tightening the
jam nut against the solenoid plunger.
3. Re-check the high idle RPM.
4. Close the engine service access doors and
shut off the engine.
F-32
Hold the