Adjusting Engine Speed - Miller Big 40 C Owner's Manual

9-6. Adjusting Engine Speed

Engine Speed
(No Load)
1850 rpm max
(61.6 Hz)
1250 rpm
(41.6 Hz)
1
2
4
3
5
Engine Speed Adjustment
After tuning engine, check en-
gine speed with tachometer or
frequency meter. See table for
proper no load speed. If neces-
sary, adjust speed as follows:
Start engine and run until warm.
Turn Process/Contactor switch
to Stick − Weld Terminals Al-
ways On position.
Standard Model Idle Speed
Adjustment
1 Adjustment Screw
2 Lock Nut
Loosen lock nut. Turn screw until
engine runs at idle speed. Tight-
en nut.
Models With Automatic Idle
Option
3 Throttle Rod / Plunger
4 Lock Nut
5 Rubber Boot
Adjustment screw is not used to
adjust engine speed when auto-
matic idle option is installed.
.
To prevent solenoid dam-
age, be sure a 1/8 in (3 mm)
gap exists between the en-
gine low speed screw and
throttle lever when the sole-
noid is held in the energized
position.
Unhook rubber boot from the so-
lenoid housing but leave con-
nected to plunger.
Loosen lock nut. Place Engine
Control Switch in Auto position.
Turn throttle rod and plunger un-
til engine runs at idle speed.
Tighten lock nut.
Hook rubber boot back onto so-
lenoid housing.
.
Be sure solenoid plunger
pulls all the way in ("bot-
toms") when energized.
Weld/Power Speed
Adjustment
.
Weld/power speed adjust-
ment must be done by the
engine manufacturer's fac-
tory authorized service
agent.
Tampering with adjustments
other than shown may affect
engine warranty.
!
Stop engine.
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