DZ 140
 

Hi,
a question about plunger and how the fuel metering works.

What is the function of the plunger?
How does it interact with the diaphagm that is adjusted by the brass screw?
As the plunger pumps same amount of fuel every stroke, where the excess fuel goes?

Perhaps the pumping, metering, injecting of the DZ have been already covered in a post, if positive pls let me have the link.

best regards
David

RE: DZ 140
 

The pump only pumps at whatever volume the engine requires for a given throttle setting so there is not any excess fuel. For example, at idle, the pump only pumps a small amount of fuel, at full throttle a large amount of fuel. The speed of the pump is governed by the number of pressure pulses it receives from the engine through timed crankcase pressure. At idle only a few pulses, at faster throttle settings, more pulses. That is as simply as I can explain it.