Injection Pump Accessories
injection pump can be used on a variety of applications; therefore, it is available with
several options as required. The options are as follows:
flexible governor drive is a retaining ring that serves as a cushion between the
governor weight retainer and the weight retainer hub. Any torsional vibrations that may be
transmitted to the pump area are absorbed in the flexible ring, therefore reducing wear of
pump parts and allowing more positive governor control.
electrical shutoff (fig. 5-19) is available as either an energized to
run (ETR) or energized to shut off (ETSO) model. In either case it will control the run
and stop functions of the engine by positively stopping fuel flow to the pump plungers,
thereby preventing fuel injection.
torque screw, used on DB2 pumps, allows a tailored maximum torque curve for a
particular engine application. This feature is commonly referred to as torque backup,
since the engine torque will generally increase toward the preselected and adjusted point
as engine rpm decreases. The three factors that affect this torque are the metering valve
opening area, the time allowed for fuel charging, and the transfer pump pressure curve.
Turning in the
torque screw moves the fuel-metering valve toward its closed position. The torque screw
controls the amount of fuel delivered at full-load governor speed.
load is applied to the engine while it is running at full-load governed speed, there will
be a reduction in engine rpm. A greater quantity of fuel is allowed to pass into the
pumping chamber because of the increased time that the charging ports are open.
will continue to increase until the rpm drop to the engine manufacturers
predetermined point of maximum torque.
Do NOT attempt to adjust the torque curve on the engine at
any time. This adjustment can be done only during a dynamometer test where fuel flow can
be checked along with the measured engine torque curve or on a fuel pump test stand.