721D slipping on one side

geoff

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Hi, and thanks for taking a moment to read my post. I have a 721D on which the right wheel appears to be slipping. It will eventually catch up but the problem seems to be getting worse and I am concerned it's getting to the point where I will get stuck with only one wheel working. When I purchased this used about three years ago, it had just been serviced and the left side motor replaced. However,when I spoke to the service guy prior to buying it, he said the had recommended replacing the right side as well. My question is that considering it will eventually catch up to the other side, isn't it more likely to be the tensioner and/or the belt rather than the motor itself? I hate to sound so cynical but I have been ripped off so many times, I am worried if I bring it to the dealer, they are going to replace the motor AND the tensioner and I would never know it was just the tensioner and or belt. I haven't delved into this motor to any great extent but trust I could just replace the tensioner and belt myself... any suggestions? Is replacing the tensioner and belt a pretty straight forward project that I could likely do without a service manual? Any thoughts would be appreciated.. thanks again

geoff
 

bobbysr

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What year is the mower ? And which transmission does it have? If its a G2, it could be a locked up tensioner - happened to me.
 

GHdiesel6

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I have a 2000 721 with the G2 trans and this happened to me too..I replaced both drive belts and replaced the tensioner idler wheel bearing and made sure i had the correct tension on the belts...Rides great now! Before I did this the mower would drive fine on flat ground but it would slip on any incline...hope this helps


and as far as doing the repairs yourself, its pretty easy...a little tight fit..just remove the inline coupling coming from the motor then loosen both tensioners and the belts will come off.. just remember the orientation..
 

geoff

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What year is the mower ? And which transmission does it have? If its a G2, it could be a locked up tensioner - happened to me.

The mower was made in 1995 and not sure what transmission it has.... how would I find out? Is it as easy as looking for model number on the side? From looking at the parts blowup on one of the web pages, I believe the part is 391207.. hope this helps.. let me know if you have any other questions or if this doesn't answer your question.. thanks again for your help..

geoff
 

geoff

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I have a 2000 721 with the G2 trans and this happened to me too..I replaced both drive belts and replaced the tensioner idler wheel bearing and made sure i had the correct tension on the belts...Rides great now! Before I did this the mower would drive fine on flat ground but it would slip on any incline...hope this helps


and as far as doing the repairs yourself, its pretty easy...a little tight fit..just remove the inline coupling coming from the motor then loosen both tensioners and the belts will come off.. just remember the orientation..

Thanks very much for your suggestions... hope to work on it this Friday but as usual, I have to order the parts and wait and hope it will keep running until I can get the parts!!!

geoff
 

bobbysr

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Being a 1995 model , your mower has the G1 transmission. G2's came out in 1998.
 

bobbysr

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Part # 391207 is the right side transmission. $1685.00. Part # 393312 is the idler - $12
 

geoff

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Part # 391207 is the right side transmission. $1685.00. Part # 393312 is the idler - $12

Update: I called the dealer who actually serviced this unit just prior to my purchasing it.. the replaced the RIGHT side transmission in 2010!!! so I am bringing it in tomorrow for them to look at in case it is that as opposed to the tensioner spring or belt... will keep you posted and thank you for your help!!!

geoff
 
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