[Vwdiesel] Bosch FI Pump Pictures and Book Reference.

[Charlie Smith]

Here's some info for those of you interested in how the Bosch injection
pump as used on the VW diesels works.

The VW's Bosch pump uses a single plunger and cylinder to create high
pressure.  The stroke of this "plunger" is constant, but the amount
of fuel actually pumped at high pressure is varied by moving a control
collar that opens a port to relieve pressure during part of the plunger's
stroke.  The plunger is moved back & forth as the injection pump toothed
pulley is turned.  This is shown in the referenced pictures.

The movement of the control collar adjusts how much fuel is pumped
per stroke.  This control collar is moved by the governor mechanism,
which is adjusted by movement of the lever connected to the throttle
cable.  The "adjustment screw" I talked about actually changes how the
outside throttle lever affects the governor mechanism.

There is a fuel distributor on the end of the pump, to select which
injector gets the "shot" of fuel.

A very good book on this stuff is a Robert Bosch book titled "Diesel
Fuel Injection".  The ISBN is 1-56091-542-0.  My 1st edition was
published in 1994.  It's about 3/8" thick, so it's not huge.

There are three pages from this book on this web page:

    http://elektro.cmhnet.org/~charlie/vwdiesel/

These pictures show the internal pump design, and explain function
and operation.

    Charlie


  Charlie Smith   charlie at elektro.cmhnet.org  614-471-1418
  http://www.elektro.com/~charlie      Columbus Ohio   USA
  http://www.elektro.com/~audi     photos & technical info

  95 S6 Quattro  -  24 PSI, RS2 6 speed, and other features
  97 Dodge Ram   -  35 PSI, 4x4 w/Cummins turbo diesel





--

 Charlie Smith   charlie at elektro.cmhnet.org  614-271-1418
 http://elektro.cmhnet.org/~charlie/  Columbus Ohio   USA
 SMS: charlie.sms at elektro.com