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ACT816

Different twists to the 6216 or T-816 Variator Q

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ACT816
Hey all, I've been going through the threads on the variators for the Simplicity 6216 and Allis T-816 tractors. I have the Allis version that is repowered with an Intek OHV 19 twin. I replaced the belts and everything works "okay" but...here's the twist. My shifting is extremely hard. The variator and all is working correctly, if I'm not careful the front wheels come up off of the ground. I have control with the lever for my ground speed but basically have to shut the engine off to switch gears. I did verify the brake adjustment as well. The clutch adjustment is at exactly 5 1/2" to the shaft. Anyone have any experience with this? I'm sure I can adjust the spring off of the clutch-to-variator to reduce the tension applied to the tranmission but this seems a bit odd. I will say, while replacing the belt, the variator freed itself up a little more so my variator works better than it has. I've been soaking the bushings every chance I get and it "popped" while swapping belts, which is what I'm suspecting the difference now compared to the last few years I've had this tractor. Any suggestions welcome! I've uploaded a shot with the snow blower attached. Dave


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ACT816
The tractor is a: 1690692. I did go through the belt stop adjustments as well. It "seems" like there is too much tension on the secondary belt. It shifts fine without the engine running and with the old belts and variator out of adjustment it shifted fine. Now, with new belts and going back through the variator adjustment the driveline seems overly tight, just from the standpoint of how it acts when I release the clutch and try to shift. The brake stop was at 3/4" space, I tightened this up to 5/8" thinking that the transmission gears were not being fully stopped (you can hear feel grinding if you try to push into the gear with the tractor running). My thought on this was to go back through the procedure and set the gap for the clutch/brake shaft to front to 6" and try it and then go to 5" and try it, and see which seemed to feel better but I keep over-thinking the way the sheaves work. It's actually a nice system but when going to think about the tension, I go from the belt tension of being close to the center of the sheave to what it does if you move the belt to the outer part of the sheave. Dave

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BLT
Those guides will make the belt slip foward off the groove and even with engine running the belt travel will cease. And to really be effective both guides be at the halfway point or widest part of the pulley. It won't hurt to gap the guides to 1/16" either.

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1Litre
If I remember correctly that has a split drive pully on the engine and a plastic bearing(washer) behind the movable sheave to allow more slip when letting the clutch pedal up for better control without leaping into engagement. Is that bearing in there.

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ACT816
I've uploaded the blow-up from the parts listing, which bushing do you mean? I still don't get why this shifts hard after going through the adjustments with the new belts. Nothing changed other than changing belts and then of course, the changes needed to walk through the variator adjustments, which I've done a couple of times now with the same results. Could the tension of the variator sensitivity spring have anything to do with this?? I did try backing this out a few turns but it didn't seem like it did much but maybe I didn't go far enough? Dave


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ACT816
Okay, quick update. So, after looking at the set-up of the variator and the belts and how the belts work when the clutch/brake is depressed, I decided to try an experiment. I set the brake travel to 6 1/4" to the shaft (interestingly, this is about 5 1/4" to the front of the pedals "hook" for the parking brake) and gave it a try. It shifts into the other gears now without an issue. I may try in 1/4" incrememts to see where the locking point is, but doing a short test ride, everything seems to work as it should. I'm guessing that as the primary belt stretches a little, I'll be able to move this back to book measurement. Is it possible that there is more belt-to-belt variation - lengthwise - than is expected by the manual?

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