Here are some videos showing an exploded view of high pressure pumps. If nothing is shown immediately please wait a few seconds…
Exploded view of a Bosch CP1 high pressure pump
Exploded view of a Bosch CP3 high pressure pump
Exploded view of a Bosch CP4 high pressure pump
Lucas Cav DPA Pump
Bosch VE Pump
CAV BPE6B Pump Timing