Description
Diaphragm for the governor commonly fitted to Bedford, Mermaid and Sabre Minimec pumps approximately 52mm in diameter
On turbo-charged diesel engines, the volume of air fed to the cylinders falls off as the speed of the turbo-charger drops. This is due to the inherent nature of the turbo-charger at low engine speeds. To prevent the emission of smoke under these conditionsa smaller quantity of fuel is required. The boost control unit provides automatic control of the maximum fuel delivery under these low speed conditions by sensing the inlet manifold air pressure generated by the turbo-charger. It reduces the maximum amount of fuel that may befed to the engine when the manifold pressure drops below a pre-determined figure. The unit consists basically of a spring loaded diaphragm, spindle, cam and fuel rod. It is fitted to the top of the governor case so that the fuel rod replaces the original maximum fuel stop. At high engine speeds, the boost pressure (taken from a point on the manifold) thrusts the diaphragm against its spring, thus moving the spindle horizontally. The spindle turns the cam,which allows the fuel rod to rise to its normal operating position, where it acts as a maximum fuel stop. When the engine speed falls, the boost pressure drops, and the diaphragm returns towards its original starting point. The spindle turns the cam, which pushes the fuel rod vertically downwards, thus reducing the effective maximum fuel setting. Adjustable minimum and maximum stops are provided for setting purposes.
Item number 414 in the exploded diagram
Fits the following pumps:
P5437-3, P5437-4, P5575-1, P5624, P5624-1, P5624-1A, P5624-2, P5624-2A, P5624-A, P5608, P5608-1, P5608-2, P5608-3, P5608-4, P5686, P5686-1, P5686-2, P5706, P5706-1, P5707, P5707-1, P5488-2A, P5488-2E, P5488-2F, P5488-3, P5488-3A, P5488-3B, P5488-3F, P5488-3G, P5488-3H, P5488-4, P5488-4A, P5525-2, P5525-2A, P5525-3A, P5569, P5569-1, P5578, P5578-1, P5614, P5614-A, P5614-B, P5614-BX, P5641, P5641-1A, P5641-2A, P5694, P5694-1, P5705, P5705-1, P5748, P5748-1, P5748-1A, P5748-2, P5748-2A, P5751, P5752, P5753, P5753-1, P5753-1A
