Picked up this QT over a year ago. It has always had a jerking when pulling up a grade going forward. Reverse and level or down grade was fine. Was going to drop the rear end and see if anything was out of line. Didn't get to it so it sat all winter. with no fluid. Yesterday I needed to mow a small pasture and wanted the QT as the deck will raise a lot higher than most. Filled it with fluid, fired it up and went off to mow. Run for about a half hour & got about half of it done, jerkin away if it tried to hold a steady pace so had to keep varying the ground speed. This morning went back to finish up. Started out the same way, wanting to jerk on up grade. Was doing a lot of forward/reverse moving and suddenly the jerk was gone. Drove it up a good hill to the shop and it ran smooth. Let it cool a while and headed back to the machine shed, up an incline into the shed and it was smooth as could be.
I have tried various things with this unit and probably put at least 2 hours on it last summer trying to work out the problem. Could it possibly have been air in the system some place that took this long to work its way out? I did go backwards fairly fast a few times. Would this have an effect on getting the air out - if that was the problem? I don't want to blow my horn to loud just yet till I see what happens next time I want to use it in a couple days.