Whew! Nice talk. Just to clarify, “..making holes everywhere” was actually one hole each in the bottom of the drives, to create a 1/8 NPT drain. The holes were drilled carefully with the cases full of oil still (as the only way to change the oil is to remove the drives and invert to drain through the vent hose or fill, which certainly would guarantee any sediment to flow all over the mechanism.) The oil in the case affectively flows the last bit of grinding out when the drill penetrated, helping to prevent what you suggest. Secondly, the lurching was a condition existing before I made this modification.You either still have air in there, not enough oil , a defective pump ( highly unlikely ) or a bad drive belt / tensioner or dragging brakes
Unless you pulled the hydros apart fully before you let loose with your Black & decker then I could guarantee you have swarf in the system so even if you get the lurching problem solved you would have wrecked the transmissions .
These things are made in a sterile dust free environment so why did you think it was OK to grab your drill & start making holes everywhere ?
A brain dead ego posting on Y-Boob ?
Its a nice concept about the drives being manufactured in a dust-free environment, but when they are in use in the field having a vent tube to the dustiest environment imaginable, its no wonder the oil gets to look so dirty. Coupled with the impossible serviceability, its simply planned obsolescence. Note how in later years these static drives were improved with external expansion/fill tanks displaying proper oil level and drain plugs encouraging maintenance oil changes.
Trying to navigate past your angry response, I had mentioned having adjusted the spring tension on the brake control shaft to different positions of tension with no change resulting. Can you or anyone offer a prescribed procedure for correctly adjusting the brakes or where to inspect for dragging brakes?