My troy built pony only has two gear speeds. Why?

Mr.Quebedeaux

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you have to get the GEAR thing out of your head if you want to get this fixed you have no gears just fixed ratios of pulley circumferences which is why I use the stepped pulley drive on a bench drill to illustrate as most blokes are familiar with them..
From what you have now said it seems like the variable speed pulley is sticking .
Without the actual model & serial numbers off the tag under the seat, we can not be 100% specific and the only parts breakdown I have on this computer is for the larger Horse model but the drive system is the same to the point that most parts interchange.
Your problem will be with the double belt pulley part # 47 .
Because of the way it is used it we call it a shive and in particular a sliding shive .
Because all 3 flanges always spin at the same speed, if you alter the circumference of the two pulleys the belt speed in feet per minute changes which changes the speed that the axle pulley rotates in rpm .
THis is what determines your ground speed .
The tension on the lower belt is controlled by the two pulleys # 35 on the bracket # 36 which rotates counter clockwise to increase the belt tension .
The tighter the lower belt is the faster the mower goes.
Your GEAR lever simply limits how far the bracket # 36 can rotate in the counter clockwise direction.
However if the sliding flange on the double pulley # 47 can not slide freely top to bottom then the effective circumferences of the upper & lower sections can not change so your ground speed can not change .

It is a simple system very robust and works very well requiring very little maintenance other than a shot of spray grease on the moving bits every year or so & belt changes.

View attachment 51071
The model # is 13WN77KS011, serial # is 1C192B40001
 

Mr.Quebedeaux

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The model # is 13WN77KS011, serial # is 1C192B40001
 

bertsmobile1

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Thank you.
Before this gets very confusing please have a look under the mower.
There are 2 variations on the drive system
One is as per the diagram already posted,
The other does not have the 2 small pulleys on the lower drive belt.
They both work the same way, they just use a different mechanism to change the tension of the lower drive belt.
 

StarTech

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Bert that actually why we ask for the model number so we can look-up the mower's actual IPL. If you bother to do that you would know how it is setup. Sorry to be blunt but you should look-up the mower IPL before guessing.

It a straight belt path for the engine to variable. Belt size is 5L x 70.90" The variable to transaxle size is 5L x 35.25" Either one these being the wrong size will cause problems. Also you can not use belts from an auto parts store as will not have the proper profile but they will still you what you ask for, they don't care.

The bracket assy that holds the variable pulley stack can wear and bind. Also can bind from rust.

The variable on this is the one the clutch pulls forward to slow the speed with a heavy pulling rearward. One other systems you are think is the one where the variable is mounted fix position on the transaxle and the other is fixed mounted to the frame. The one with the moveable variable is the troublesome one of the three systems.
 

bertsmobile1

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I stand in the Dunces corner.
The vari drive with a pivoting variator is totally new to me .But I now know it is troublesome .
From the pars books looks like it was introduced around 2011 becaus there are 2 from that year, one with the old system & one with the new system.
We do not get all of the USA models down here, in fact I have not seen a new Troy-Bilt branded ride on since MTD took them over.
However MTD also took over the local Rover brand but again never seen one in the shop.
And as usual the MTD australia site tells me to contact a dealer if I try to get any information.
I think all of the mower IT geeks down here were once ASIO spies .
 

StarTech

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Yes the wear just any pivot mount like idler arms. And I do understand the different parts of the world has different operations. I just had to find a ipl for Poulan PL3314 chainsaw that all the US site were converting to a P3314 which was the wrong saw. Using my resources I had to first find the PL3314 info which had a Husqvarna model number. Using that model number I found the IPL on a Czech Republic website. If looking info a Rover I ask for help on ODK website that I am a member of where I provide help Briggs engines in exchange for the help if I ever need it.

Once one of the hardiest IPLs and service manuals for me to get copies of were the Stihl ones. I have since develop a pretty good resources for them. Having the parts drives the local Stihl dealer crazy as they want to know where I am getting my info. All I tell them is that "If I tell you then I have to kill you.". With Stihl being as aggressive as they are about websites having these available for downloads I have to keep them stored privately in an encrypted format.

As with any info knowing how to search for it is the key and I have gotten fairly good in the last ten years.
 

bertsmobile1

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Getting off topic, I am well aware of these things.
When I started I was already a compitent mechanic so engines were no problem.
Chassis were another thing all together.
Back then it was a ration of about 4:1 research hours to work hours.
Seven years latter is is about 2 :1
Shame I can not bill for them.
Stihl have done themselves a big diservice from my point of view as they forced me to find alternative sources so now 99% of stihl parts I fit come direct from China, the Phillapines, Hong Kong or Japan .
So that is better than a grand the local Stihl warehouse / dealers of my money they do not see.
Further complicated that in order to reduce Stihls logistical costs they have put minimum order values on their dealers so if I need to buy a part I have t ring a dozen different shops to see who is about t put an order in that week.
 

StarTech

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Yes are getting off topic. Hope Mr.Quebedeaux will chime in soon as to where he stands on this now.
 

Hammermechanicman

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I will assume you guys know about HL Supply for aftermarket chainsaw parts. None of my customers are loggers, just weekend wood cutters. Nobody has complained about affordable aftermarket parts. I have also built 2 of the Hutzl china clone saws. A 361 and a 660. Both of which are modified. Have cut a lot of wood with both and still going fine. If you look hard enough you can find a hacked copy of the 2012 mediacat file for all stihl products. IPLs and service doc.
I am waiting for someone to hack the new software controlled saws like the JD stuff from eastern europe.
 

Mr.Quebedeaux

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you have to get the GEAR thing out of your head if you want to get this fixed you have no gears just fixed ratios of pulley circumferences which is why I use the stepped pulley drive on a bench drill to illustrate as most blokes are familiar with them..
From what you have now said it seems like the variable speed pulley is sticking .
Without the actual model & serial numbers off the tag under the seat, we can not be 100% specific and the only parts breakdown I have on this computer is for the larger Horse model but the drive system is the same to the point that most parts interchange.
Your problem will be with the double belt pulley part # 47 .
Because of the way it is used it we call it a shive and in particular a sliding shive .
Because all 3 flanges always spin at the same speed, if you alter the circumference of the two pulleys the belt speed in feet per minute changes which changes the speed that the axle pulley rotates in rpm .
THis is what determines your ground speed .
The tension on the lower belt is controlled by the two pulleys # 35 on the bracket # 36 which rotates counter clockwise to increase the belt tension .
The tighter the lower belt is the faster the mower goes.
Your GEAR lever simply limits how far the bracket # 36 can rotate in the counter clockwise direction.
However if the sliding flange on the double pulley # 47 can not slide freely top to bottom then the effective circumferences of the upper & lower sections can not change so your ground speed can not change .

It is a simple system very robust and works very well requiring very little maintenance other than a shot of spray grease on the moving bits every year or so & belt changes.

View attachment 51071
I changed the upper and lower transmission belts because I noticed a good bit of slack in the upper one. The little thing that slides up and down on the pulley moved freely. It is not stuck.the lawn mower slowed down a good bit. But I still only have one gear.only one speed even though I switch gears. I stay the same speed. Any information would be greatly appreciated.
 
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