Hello, I have read lots and lots of great information on this forum relating to the HST and adjustments, etc. I have been reading and messing around with this for a few weeks and have not figured out the issue, so hopefullly you all can help with a couple of ideas.
Kubuta RTV1100 (2011 ish). Hangs in forward - continues forward under just the right circumstances... for some reason this is usually when I make a slow sharp turn around the same tree. You can't force it out of gear, you just have to wait until it slows and rolls back slightly, then you know its fully disengaged. Driving across the field, I test occasionally and it decelerates abruptly indicated that its fine. Every once in a while it sticks, mostly going uphill I think, and when I let off the pedal, it does not imediately decelerate and thats when I know it sticks. If I continue pressing forward while its sticking, it does not seem to want to advance the swash plate and give me more hydraulic ratio, the engine just revs. (thats a guess at whats mechanically going on). The oil has been recently changed (Super UDT) and is possbily a little high but certainly not low.
(I am going to try to use the verbiage /component names directly from the service manual)
My first thought was the servo regulator or servo piston was sticking. I pulled the servo regulator off and inspected it, I did not pull the cap off the end and remove the spool, but it was clean and traveled freely. I also pulled both end caps and the cover off the servo piston and moved it back and forth. I could not figure out how to remove the guide block to remove the servo piston, but it was clean and seemed to move fine back and forth through the small amount of travel allowed by the moment of the swash plate. I put everthing back together to see if by some luck it fixed itself... it did not. I also inspected the forward check and high pressure relief valve. This is supposed to measure in at 38.6-38.7 mm and I am measuring 38.85mm - I did not mess with it at this time as it was clean and otherwise seemed in good shape.
I would love some clarity here, I read much about the dynamic braking valve (the one people replace with the solid aftermarket one) and based on the location and pics, I would think its the same as this check and high pressure relief, but that doesn't seem to make sense. Based on the discription, this valve sets the main working pressure.
oh, and yes, I have adjust the linkages and I can watch the arm of the servo regulator move back to neutral even though I continue moving forward.
Next on my list was to inspect the charge relief assembly, but I doubt that is going to turn up anything.
Also, I should mention that the brake relief valve actuated by the brake pedal is rusty on the outside and appears to be stuck. That is also on my list to remove and clean up but I dont think that is the issue here as it has not moved during all these tests. I am not sure if I am going to dump a lot of fluid as its on the bottom of the transmission.. any insight on this would be helpful.
Any other ideas would be much appreciated...
Kubuta RTV1100 (2011 ish). Hangs in forward - continues forward under just the right circumstances... for some reason this is usually when I make a slow sharp turn around the same tree. You can't force it out of gear, you just have to wait until it slows and rolls back slightly, then you know its fully disengaged. Driving across the field, I test occasionally and it decelerates abruptly indicated that its fine. Every once in a while it sticks, mostly going uphill I think, and when I let off the pedal, it does not imediately decelerate and thats when I know it sticks. If I continue pressing forward while its sticking, it does not seem to want to advance the swash plate and give me more hydraulic ratio, the engine just revs. (thats a guess at whats mechanically going on). The oil has been recently changed (Super UDT) and is possbily a little high but certainly not low.
(I am going to try to use the verbiage /component names directly from the service manual)
My first thought was the servo regulator or servo piston was sticking. I pulled the servo regulator off and inspected it, I did not pull the cap off the end and remove the spool, but it was clean and traveled freely. I also pulled both end caps and the cover off the servo piston and moved it back and forth. I could not figure out how to remove the guide block to remove the servo piston, but it was clean and seemed to move fine back and forth through the small amount of travel allowed by the moment of the swash plate. I put everthing back together to see if by some luck it fixed itself... it did not. I also inspected the forward check and high pressure relief valve. This is supposed to measure in at 38.6-38.7 mm and I am measuring 38.85mm - I did not mess with it at this time as it was clean and otherwise seemed in good shape.
I would love some clarity here, I read much about the dynamic braking valve (the one people replace with the solid aftermarket one) and based on the location and pics, I would think its the same as this check and high pressure relief, but that doesn't seem to make sense. Based on the discription, this valve sets the main working pressure.
oh, and yes, I have adjust the linkages and I can watch the arm of the servo regulator move back to neutral even though I continue moving forward.
Next on my list was to inspect the charge relief assembly, but I doubt that is going to turn up anything.
Also, I should mention that the brake relief valve actuated by the brake pedal is rusty on the outside and appears to be stuck. That is also on my list to remove and clean up but I dont think that is the issue here as it has not moved during all these tests. I am not sure if I am going to dump a lot of fluid as its on the bottom of the transmission.. any insight on this would be helpful.
Any other ideas would be much appreciated...