Technical Information
C.
GAIN
and
STABILITY
adjustments may require minor changes after engine load is applied.
Normally, adjustments made at no load achieve satisfactory performance. A strip chart
recorder can be used to further optimize the adjustments.
If instability cannot be corrected or further performance improvements are required, refer below to
the
SYSTEM TROUBLESHOOTING
section.
Starting Fuel Adjustment
The engine’s exhaust smoke at start-up can be minimized by completing the following
adjustments:
A.
Place the engine in idle by connecting
Terminals M
&
G.
B.
Adjust the
IDLE
speed for as low a speed setting as the application allows.
C.
Adjust the
STARTING FUEL CCW
until the engine speed begins to fall. Increase the
STARTING FUEL
slightly so that the idle speed is returned to the desired level.
D.
Stop the engine.
Method 1
Method 2
Start the engine and accelerate directly to
the operating speed
(Gen Sets, etc.).
Start the engine and control at an idle speed
for a period of time prior to accelerating to
the operating speed. This method separates
the starting process so that each may be
optimized for the lowest smoke emissions.
Remove the connection between
Terminals
M
&
G.
Start the engine and adjust the
SPEED
RAMPING
for the least smoke on
acceleration from idle to rated speed. If the
starting smoke is excessive, the
STARTING FUEL
may need to be adjusted
slightly
CCW.
If the starting time is too long, the
STARTING FUEL
may need to be adjusted
slightly
CW.
or
Replace the connection between
Terminals
M
&
G
with a switch, usually an oil pressure
switch.
Start the engine.
If the starting smoke is excessive, the
STARTING FUEL
may need to be adjusted
slightly
CCW.
If the starting time is too long, the
STARTING FUEL
may need to be adjusted
slightly
CW.
When the switch opens, adjust the
SPEED
RAMPING
for the least amount of smoke
when accelerating from idle speed to rated
speed.
Idle Speed Setting
If the
IDLE
speed setting was not adjusted as detailed in
‘Starting Fuel Adjustment’
section, then
place the optional external selector switch in the
IDLE
position. A
CW
adjustment to the
IDLE
adjustment control will increase the idle speed set point. When the engine is at idle speed, the
speed control unit applies droop to the governor system to insure stable operation.
