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Brettw

728 gear grinding, Updated

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Brettw
Need some help here. I have been trying to adjust the belt on my FIL's 728. When the clutch/brake pedal is fully depressed, the belt continues to turn the rear driven pulley on the transmission. The brakes are good and work fine. The belt has plenty of slop or play in it when the pedal is depressed. I can't see any stops, brakes, or belt guides that would help this. Anybody familiar with these? I know my old 728 would grind the gears sometimes, but this is a constant grind every time you are initially putting it in gear. Fully depressed, the idler pulley actually touches the driven pulley, so I don't think there is any more adjustment in that direction. Any help would be appreciated. Per all suggestions, I adjusted the belt guides to within 1/8-1/16". Problem immediately solved. So as an FYI to all, and a thank you for a great lesson learned, it does make all of the difference in the world.

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HubbardRA
Does it have the cover around the front pulley. If so, make sure it is no more than 1/8 inch from the pulley. That is basically a belt stop. When the belt is released and tries to expand in a circle, the cover catches that section of the belt and keeps it from staying in contact with the front pulley.

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Brettw
Thanks for all of the help. This tractor has a newer replacement engine in it, and seems to be missing the belt stops completely. I have a set from anotherr tractor I think will work, and that should fix the problem. Thanks to BLT for the PDF of the 728.

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timflury
I hate that when people repower these tractors and they see these parts, "What were these for? I don't think we need them." and the belt stops get tossed. Same thing happened on my Serf when I first had it.;)

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steve-wis
I got a nice 616 yeoman for almost nothing from a guy because it was grinding the gears. I offered to look at it and fix it for him but he said no, didn't want any tranny problems. On mine the stops were there but pushed around to the frame. Five minutes and it was fixed. The beauty was the guy lives across the street, so I drove across to show him how it worked. Yes, he still talks to me, but he seemed a bit put off. Some people, you just can't help them, you know? Moral of the story, those belt stops are really important and really do work great, so don't bypass them! Steve

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Brettw
I also think that having the importance of them and what they actually do explained, helps with the understanding. Up until this, I always figured they were to keep the belt on the pulley. So the fact that they were missing never came into my mind that that would cause the gears to grind. So as per the usual here, I learn something new every day.

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