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DavidScinto

AC620 Drive Belts

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DavidScinto
Hello out there! I am a brand new member. I bought an AC620 2 years ago to plow snow, rake a gravel driveway, and mow. Gotta say, I love this tractor! Anyway, the matched pair of drive belts connecting the engine to the drive train broke. It looks like I have been running on just one since I bought the tractor. Can anyone advise the best (easiest) way to change the belts? I have a manual, but it doesn't specifically have a procedure. Can anyone help a new member? Thanks, David

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4xbill
It's been a while since I did mine... I used a ratchet strap to keep the clutch disengaged and was able to slip the belts off the pulleys, then released the clutch and snaked the belts off. Reversed to get the new belts on. Like I said, it's been a while, so I dont know if I missed steps.

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DavidScinto
Hello 4X Bill. Thank you very much for your reply. The ratchet strap is a great idea and I will definitely use your suggestion. I guess my concern is, do I have to disconnect the drive train to get the belt on? I suspect that I do, but where is the easiest/best way to make the separation? If you have any suggestions, I would really appreciate it. I am a novice mechanic in training... being trained by my tractor that is! Best regards

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4xbill
Ok, going off of memory here... 1. Depress clutch to disengage and use a ratchet strap to keep it disengaged. 2. With the clutch disengaged, slip the belts off the top pulleys towards the back of the tractor 3. Release clutch 4. Slip the belts down and then forward between the upper and lower pulleys and they're off. Reverse to put the belts on. You shouldn't have to disconnect anything.

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RBE17
David, I don't know if you got your belts changed or not. If not, here's some more information. If your 620 has a rear pto, you will have to disconnect the bolts from the pto yoke to the crank pulley. W/ some careful maneuvering the belts will fit between the yoke and the pulley. Be careful not to break the fiber disk. Good luck, Steve.

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DavidScinto
Hello RBE17, Yes, I have a rear PTO and that was my question... where to break the rear PTO. I mistakenly referred to it as the drive train in my earlier message. Well, I got into it yesterday and I did exactly as you suggested, but I removed the fiber disk as well. Hopefully, I won't break the disk when I reinstall it! Why would this be made of fiber rather than metal? Thanks for your replay, i do appreciate all the great suggestions. David
quote:
Originally posted by RBE17
David, I don't know if you got your belts changed or not. If not, here's some more information. If your 620 has a rear pto, you will have to disconnect the bolts from the pto yoke to the crank pulley. W/ some careful maneuvering the belts will fit between the yoke and the pulley. Be careful not to break the fiber disk. Good luck, Steve.

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RBE17
David, The disk is a vibration / noise damper. That's why it's made of fiber and not metal. I believe it's a piece of phenolic. I'm actually doing this parallel to you as I am doing some desperately needed maintenance on my 4040. Later, Steve.

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DavidScinto
Steve, It's nice to know someone out there is sharing my pain! That explains it. Thanks. If you have anything new to report, let me know and I will do the same. I likely won't get back to it until a little later in the week. Best regards, David
quote:
Originally posted by RBE17
David, The disk is a vibration / noise damper. That's why it's made of fiber and not metal. I believe it's a piece of phenolic. I'm actually doing this parallel to you as I am doing some desperately needed maintenance on my 4040. Later, Steve.

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D-17_Dave
The fiber disc is in effect the universal joint for the rear shaft. It allows for small variations in angle between the engine and rear shaft. You'll find them also on both ends of the main transmission shaft that works off the clutch. I would also recommend changing the neoprene inserts around the shoulder bolts in the shaft base. These are the dampeners and over time get worn and hard. To keep the shaft properly centered and reduce vibration these need to be soft so they are tight around the bolts. Watch out when you put the disc back in as the washers are designed to be directional. You'll notice the washers are stamped out and have a rounded edge and a sharp edge. The rounded edge must face the disc so it doesn't cause a tear in the disc. You'll find all drive line washers on Simplicity/AC tractors to be like this. With the main part of this topic covered, I'd recommend spending some time around the sight and time permitting do a search of related topics under 620/720/9020/Powermax sized tractors. This will give you tons of practical articles on problems and fixes on these tractors. You can also get a copy of the parts/repair/and owners manuals. That will cover nearly anything you'd need to properly maintain these great tractor.

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DavidScinto
Hello D-17 Dave, I can't tell you how glad I am to have become a member to this sight! The information I have received from other members has been invaluable and you have saved me from almost certain trouble with your advice. I have only been a member for a very short time and just have not had the time to research the site properly, but I am looking forward to doing so. With regard to the neoprene inserts, if you wouldn't mind giving me a bit more advice... is this something I need to locate and purchase or is it something that I need to fabricate? When I disassemble the rear shaft, I did not see any neoprene inserts. This doesn't surprise me as I have found a lot of issues with poor quality workmanship/maintenance on this tractor. The previous owners weren't very concerned with doing it right. I have never and probably will never use the rear PTO, but if it is there, I want to do it right! Everything I do improves the tractor. I have the AC repair/parts/and owners manuals for the tractor, but what I don't have is the Simplicity parts manual with the Simplicity P/N's. Is this available on the sight? If so, I hate to be a pain, but can you point me in the right direction? Kind regards, David

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D-17_Dave
Item #7 on page 28 of the above file link. These parts are all available through Simplicity and any dealer should be able to cross your tractor's numbers over to their part numbers. Just a little side advice, if your local dealer is less than willing to supply your parts then walk out. Most dealers are more than willing to help and may even have your normal wear item parts. But some are less than enthusiastic about such an old tractor and may want to concentrate on selling you a newer model rather than supplying you parts. There are several sight sponsors than stock most of these parts and will be glad to help you out.

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DavidScinto
What can I say? I am blown away! You have been a tremendous help and eased my mind. When I bought this tractor I knew it was risky buying an older machine. Could I find information? Parts? etc... I didn't have a lot of money to spend. My wife thought I was nuts! But, like it or not I have a 700 foot long gravel driveway to maintain including plowing, grading, and raking and I needed a machine to do it. Those toys they sell at Home Depot just would not stand up to the task. I wish I knew about this sight a long time ago. I am now confident that I can maintain and even improve this machine myself. It really is a load off my mind. I am a member for life! Thanks again.

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