QuestionQUESTION: While running our round baler a few days ago, our 1896 pto developed a problem of not always stopping with the lever. One time it would stop properly, next it would run continuous whether the lever was in the on or off position. (I tried baling with it off to check if it was just free wheeling or actually running. Baler ran fine so I was assuming the pto was actually engaged.)
This tractor has had a previous and ongoing issue with the pto snapping out of gear when engaging the powershift, especially downshifting. (I pretty much ran the tractor all of the time with my hand on the lever, so it really didn't happen very often recently.) Because of this, though, my first thought was that the brake wore out and now it will free wheel, but because it operates the baler properly, I think some how it is actually fully engaged. Could there be a problem in the valve body or something else?
ANSWER: Hello,
The pto lever jumping out when shifting or pushing in the clutch pedal is a common problem on these. There is a detent adjustment screw inside the fitting on the pto control valve where the pto clutch pressure tube attaches to the valve. Remove the tube and use an allen wrench inside the fitting to turn the screw in slightly to increase detent pressure. But first make sure that when the lever is in the engaged position, that it doesn't hit the end of the slot in the console. Adjust the cable if necessary so that it engages fully before the lever hits the end of the slot. If the pto will still run the baler when disengaged, there is more wrong than the brake. I have a tee fitting that I put in the pressure tube to the pto clutch, then I install a gauge on the tee so that I can see what the pressure is to the pto clutch while engaged or disengaged. If it shows pressure to the clutch in the disengaged position, then there is a problem with the valve or cable. If it shows no pressure to the clutch while disengaged, then there is something wrong inside the pto. There should only be pressure to the brake when disengaged.
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QUESTION: Thanks. I adjusted the cable already, and I think there is a possibility that was too sloppy to allow it to disengage. As for the detent adjuster screw, how do you define slightly. Do I turn it a certain fraction of a turn, or do I have to estimate with regard to the frequency and ease at which the pto would jump out of gear?
Answer It's trial and error. All you can do is guess how much to turn the adjuster screw, install the pressure tube, and run the tractor and try it. If it's still not right, then do it again. I usually turn the screw 1/2 turn at a time and try it. For safety reasons, the lever is supposed to return to neutral if the engine is shut off with the pto engaged, so that the pto doesn't start running unexpectedly when the engine is started again. If you turn it less than 1/2 turn, you probably won't notice any difference. If you turn it too much, it might make the detent bind up and it will be hard to shut the pto off, and it won't return to neutral if the pto is on when the engine is shut off.
