Johnny

A few questions for you..

1)Have you had a compression test? If so what were the results? Poor compression in one or more cyls. will cause a rough idle as will contaminated or poor quality fuel.

2)Is the rough idle a regular rythm or is it hunting (i.e. uneven RPM)?

Slacken each injector pipe in turn while idling and note any missing or knocking cylinders.

Your problem could be simply your pump calibration out - very sensitive at idle as the fuel vol. is very small, just a couple of drops. Re-calibration would have no benefits other than smoothing out the idle and will cost you $$$$! But can you live with a rough idle??

There is no "damper" inside that pump. Some are fitted with a damper in the throttle linkage, a small shock absorber about 3 inches long.

There are two adjustment srews with locknuts on the rack lever at the back of the pump, one is idle adjustment and the other max delivery. I guess one of these is the screw you refer to?

(Check the spring on the linkage is pulling the rack lever firmly onto the idle adjust stop)

__________________
Beagle