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TomF

Question re. B-112 variable belt drive

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TomF
We have a B-112 that appeared to need a new variable drive belt. It was quite worn, and the tractor crawls along like the belt is falling deep into (either of) the pulleys, causing quite a speed reduction. We hit the Simplicity dealer up for a new belt ($56 I think) and installed it. It seems way too tight now, and pushing the clutch never seems to loosen it up enough for it to stop so we can properly shift gears. I think we've adjusted the clutch pedal for max. disengagement throw, but who knows.. Any ideas or guidance? Thanks very much! Tom and Peter Feldpausch

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Nothing beats experience!

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Kent
Tom, The key to "clutching" is the little, angled belt guide/stop on the idler pulley on the variable drive mechanism. When properly adjusted, this stop will "pinch" the belt just enough against the idler, when the clutch pedal is all the way down, so that the belt will slip on both the other pulleys (bevel gear box and transmission). When the clutch pedal is released, the belt must move freely without touching this guide/stop. You loosen the bolt on the center shaft of the idler pulley just a bit to adjust it. It simply swivels back and forth to adjust. The adjustment procedure (Step 3) shows a measurement of distance from this belt stop and the rear axle. Note that I've seen two different dimensions that were about 1/2" different, based upon the make/model of tractor.... I've tried both, and neither worked without additional "fine-tuning." If you'll notice, when you press the clutch pedal down, the idler pulley will pivot forward. It's this pivoting that changes the angles enough for the belt guide/stop to lightly "pinch" the belt. Also, make sure that the long, flat belt guide on top (between the two pulleys) is correctly adjusted to the defined clearance. This helps hold the belt "flat" between the pulleys, epecially when clutched, because there's a natural tendency for these stiff belts (especially new) to curve back out to a round or oval shape... This curvature keeps them in tighter contact with the drive pulleys (which you don't want while it is clutched). I just went through this, having replaced the drive belt on my B-210 this spring. It just takes a bit of "fiddling and tweaking" to get the belt guide/stop to stop the belt from moving, yet not rub when the clutch pedal is out.... Good luck. Perhaps some others have "secrets" or "tips" but I've found this to be time-consuming to get it just right.... Good luck! Let us know if this solves it. BTW -- I've linked the adjustment procedure just in case you need it... Kent[A href='http://www.simpletractors.com/service/vari-drive_adjustment.htm']http://www.simpletractors.com/service/vari-drive_adjustment.htm[/a]

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