Miller Electric 251 NT Welding System User Manual


 
OM-486 Page 26
7-6. Adjusting Engine Speed
Ref. ST-801 942-C / ST-800 397-A
After tuning engine, check engine
speeds with a tachometer (see
table). If necessary, adjust speeds
as follows:
Start engine and run until warm.
Turn A/V control to max.
Idle Speed Adjustment
1 Throttle Solenoid
2 Mounting Screw
Loosen two mounting screws.
3 Governor Arm
4 Carburetor
5 Idle Speed Screw
Pull governor arm away from
carburetor and hold while making
the following adjustment:
Turn idle speed screw until engine
runs at idle speed (see table).
Release governor arm. Place
Engine Control switch in Run/Idle
position.
6 Carburetor Stop
With solenoid energized, slide sole-
noid until idle speed screw just
touches carburetor stop. Tighten
solenoid mounting screws.
7 Governor Arm Extension
Check for smooth operation, and
readjust solenoid position if
necessary.
Weld/Power Speed Adjustment
Place Engine Control switch in Run
position.
8 Weld/Power Speed Rod
9 Locking Nut
Loosen nut.
10 Adjustment Nut
Turn adjustment nut until engine
runs at weld/power speed. Tighten
locking nut.
Y Stop engine.
11 Sensitivity Spring
See engine manual for governor
sensitivity adjustment.
2200 ± 100 rpm
3700
± 50 rpm
1/4, 3/8 in
Tools Needed:
Left Side
6
10 8
7
1
911
3
2
2
4
Top View
5