Bosch type fuel pump
The most common fuel pump used on auxiliary diesel engines is the Bosch type.
This is a cam operated jerk pump with a helical groove on the plunger to control the fuel cut off and therefore the quantity for fuel delivered to the cylinder for combustion.
These pumps can be arranged singly along the camshaft with one at each cylinder position or they may be housed in a single block.
Each pump unit contains a pump plunger and guide together with a spring loaded delivery valve and its seat.
Plungers and guilders are not interchangeable they should be treated as combined units or elements.