The spool should move smoothly, but some oil behind it may be causing it to hang up slightly when you push it into the bore. By all my manuals it should have two washers, but I don't remember how many my 4018 has, another washer will increase spring tension, try a second washer. This holding spool moves when the travel lever is moved by the operator and will stay moved until the pump pressure decreases to the point where it gets close to to the pressure caused by the motor becoming a pump as in rolling down a hill, then the spring tension moves it into the holding condition.
There was metal particle residue in mine when I removed the cap several years ago. My 4018 doesn't have a return filter and the Hydrabagger motor had been replaced by the PO. I suspect that the crud was from the Hydrabagger motor failure. The bottom of my oil tank also has more crud than my former 448 had in it's oil tank, but this 4018 has over 2,100 hours on it and come to think of it my 448 had almost 2,000 hours when I sold it!!!
Soma day Ima gonna clean it out, but it is a low priority at present!!!!! :crazy:
Mad Mackie in Taxonnecticut :mrgreen: :mowlawn:
