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ROLL PIN IN TRANS


mr_emerson

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Im rebuilding the trans on my B-110 and when opening the cases i found the roll pin to have a bearing jammed in it, also found a bearing laying in the bottom of the trans. I looked in the service manual as it says nothing about this. Does anyone have an explanation? By the way, i want to thank the members for pointing me to the dealer in New Jersey for parts, I called looking for seals,bearings and a gear and they had them in stock, i spoke to Pam who was very helpful. There web site is http://home.att.net/~jnem/index.html




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The one you found inside likely came outta one of the shift Forks. There should be one in each with a spring behind them. It's possible the one in the roll pin is your other one if you don't have it. How it flew into there when launched by the spring as you pulled it apart, I can only rely on ---- happens.:p
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Hi, Maybe someone wondered what the inside of a tranny looked like before you had it and lost a shift detent ball and never found it. If it was in there loose, you are VERY lucky that it didn't get picked up in the grease and try to increase the spacing of the teeth on a couple of meshing gears. (in plain words really break a bunch of stuff) The stop pins come from the factory with the balls pressed in them. A it increases the tension or pressure in the hole and B It makes the OD slightly larger to prevent the hanging up in gear problem. These pins and wear in the shift forks are the reason these units hang up in gear. When the shift finger slides back and forth from the front fork to the rear fork, these pins provide the neutral lock out. As the forks get worn where the finger pushes them, they get little dished out wear areas. Now lets say you are in 1st gear and as you are going to neutral, you are also pulling back on the shift lever. On the shift rails there are grooves where the detent balls pop in to hold the fork in either 1st or 3rd or neutral. Now lets say the fork has a little groove where the finger has worn. This pin keeps the finger in the fork until the fork gets to neutral and the detent drops in allowing the finger to slide back to the rear fork between these roll pins. This is how it is supposed to work and usually does when new. Now lets look at our worn tranny. As you are going to neutral, you are pulling back on the shift lever at the same time. The finger starts to pull the fork to neutral, but as the detent ball is being raised, the wear in the fork and the roll pin allows the finger to slip out of the groove in the fork and between the fork and the roll pin. The fork then snaps back into 1st gear because the detent hasn't crossed over the flat to the neutral groove, and it snaps back into 1st. The finger is out of the front fork and can move to the 2nd and rev fork and shift that, but when it does it locks the tranny in 2 gears. The front fork is in first and since the groove for the finger is behind the roll pin now there is no way the finger can get back into the fork. Thus when the shift lever is in neutral, the tractor operates in 1st gear. My old bent screwdriver I made in the early 70s allows you to get in and pull the fork out to nertral and then the tranny is normal. To prevent this from happening when you shift, go straight across until the fork is in neutral THEN slide the lever back or forward and then straight across and you will not leave it hung in gear. While you have this tranny apart, there are some height specs in the Large Frame Tractor shop manual Pulling these roll pins up to about .010 closer than the called out height will help compensate for wear in the shift forks and usually stop the "hung up in gear problem" I don't remember the specs, but look in the book and put them about .010 closer and it should fix this. I usually pull them with a large vise grip and use a slide hammer puller on the adjustment screw on the wrench. The pins are pretty tough, but don't pull tooooo sideways or you could break them off. They cannot be drlled out, and you have a choice of taking them to some one with and EDM "Electronic Discharge Milling" machine and having them burned out, or drilling behind them and punching out the stub and then plugging the hole. Good luck, Happy Holidays, Al Eden
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  • 3 weeks later...
Thank You Al: Today i received my trans parts from dealer and when opening the package i found the roll pins to have a ball bearing in them. So,, for the record, that's the way there made. AL, so i need to pull out each pin .010? Thank you for sharing your knowledge
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Hi, After you pull them out .010 put the cover on the tranny and be sure the finger slides back and forth between them without any drag. If so this will virtually eliminate any hanging up in gear. If they drag, drive them in a couple of thousandths. Al Eden
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