Adjusting Engine Speed - Miller Big Blue 302D Owner's Manual

8-5. Adjusting Engine Speed

Tools Needed:
3/8, 7/16 in
Standard Models
2
1
Models With Automatic Idle (Optional)
4 3
5
6
Y Stop engine and let cool.
Engine speed is factory set and
should not require adjustment. Af-
ter tuning engine, check engine no
load speed with a tachometer or fre-
quency meter (see table for no load
speeds). If necessary, adjust speed
as follows:
Start engine and run until warm.
On CC Models, place Stick/TIG
switch in Stick position.
On CC/CV models, turn Process/
Contactor switch to Stick − Elec-
trode Hot position.
Standard Models:
1 Engine Speed Adjustment
1850 rpm Max.
Screw
(61.6 Hz)
2 Locking Nut
1250 rpm
(41.6 Hz)
Loosen nut. Turn screw until engine
runs at weld/power speed. Tighten
nut.
.
Do not set engine speed higher
than specified.
Models With Automatic Idle
(Optional)
3 Throttle Rod
4 Locknut
Loosen locknuts. Place engine
control switch in Run/Idle position.
Turn throttle rod until engine runs at
idle speed. Tighten locknuts.
5 Engine Speed Adjustment
Screw
6 Locknut
Place engine control switch in Run
position.
Loosen locknut. Turn screw until
engine runs at weld/power speed.
Tighten locknut.
.
Do not set engine speed higher
than specified.
Y Stop engine.
Close door.
Ref. 802 313 / 802 489
OM-497 Page 35