# HS724TA track drive chatter/slip under load



## nhwylee (Dec 7, 2018)

First post and of course looking for help/advice. I have a new to me HS724 track model that works fine until the tracks encounter resistance. The tracks stop turning and the drive chatters and sounds like plastic gears slipping past each other. Any idea where I should look first? It is not the sprockets slipping inside the tracks; that was my first thought.


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## JnC (Feb 21, 2014)

Yup, just saw that one a HS828, the pin on the driveshaft is either broken or the gearbox is not put together properly by someone who might have rebuilt it. The pin is not numbered in the diagram but its the one on the part # 7 (driveshaft). A gearbox rebuild is in order.


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## orangputeh (Nov 24, 2016)

ouch!

JnC should know. how many have you rebuilt J?


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## nhwylee (Dec 7, 2018)

After some more reading, I went out and confirmed the shaft going into the right gearbox continues to turn when the tracks stop. It looks like I got a correct diagnosis from this forum in just a few minutes. 

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## nhwylee (Dec 7, 2018)

Got it apart today. To my surprise the pin was not broke. The gear #23 had a chipped tooth, and shaft #3 had a worn spline. Neither of them alone appeared bad enough to slip, but I suspect worn bushings and bearings were allowing gears 22 & 23 to slip past each other at the chipped tooth.

It looks like the transmission has been updated to reduce the torque on that pin in shaft #7. I've ordered the updated parts and will post pictures of them side by side with the old ones.

This machine has turned into a money pit but there's no sense crying over spilt milk; fix it and move on.

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## orangputeh (Nov 24, 2016)

nhwylee said:


> Got it apart today. To my surprise the pin was not broke. The gear #23 had a chipped tooth, and shaft #3 had a worn spline. Neither of them alone appeared bad enough to slip, but I suspect worn bushings and bearings were allowing gears 22 & 23 to slip past each other at the chipped tooth.
> 
> It looks like the transmission has been updated to reduce the torque on that pin in shaft #7. I've ordered the updated parts and will post pictures of them side by side with the old ones.
> 
> ...


well , good news that the pin was not broke. taht axle is also expensive. look at it this way , once you service and repair this right side gearbox , you'll be good for another 20 years or more. seriously. the engines last forever and with proper maintenance the rest of the unit will also.

looking forward to your updates as I am learning to do this as well on a 928.

thank you.


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## Honda1132 (Sep 2, 2016)

nhwylee said:


> Got it apart today. To my surprise the pin was not broke. The gear #23 had a chipped tooth, and shaft #3 had a worn spline. Neither of them alone appeared bad enough to slip, but I suspect worn bushings and bearings were allowing gears 22 & 23 to slip past each other at the chipped tooth.
> 
> It looks like the transmission has been updated to reduce the torque on that pin in shaft #7. I've ordered the updated parts and will post pictures of them side by side with the old ones.
> 
> ...


Had a similar issue with my 1132 a couple of years ago, the spline on 3 and the interlocking gear were stripped. I bought the 2 new parts and some new bearings, put it back together and it has worked like a top since. I enjoyed taking it apart and getting an appreciation for how things work on the machine.


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## JnC (Feb 21, 2014)

Most of the time the reason why the gears lose their teeth cause being outta whack for the lack of better terms, either the plastic bushing on the main driveshaft (part # 6) is missing/worn or the plastic bushing in the chassis plate (part # 4) has perished. I have seen cases with hole for the plastic bushing in the chassis plate is either enlarged or damaged due to the middle cog (part # 3) wondering all over the place. A worn bushing is usually also the reason why the machine would track towards the right a bit more than the left, beside having worn bearings.


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## nhwylee (Dec 7, 2018)

orangputeh said:


> well , good news that the pin was not broke. taht axle is also expensive. look at it this way , once you service and repair this right side gearbox , you'll be good for another 20 years or more. seriously. the engines last forever and with proper maintenance the rest of the unit will also.
> 
> looking forward to your updates as I am learning to do this as well on a 928.
> 
> thank you.


I ordered the axle; I'll put the old one on fleabay if it is not worn when compared to the new one. The two gears were almost as much as the gear set with the axle so buying the gears alone didn't make sense. The individual gears and shaft for later model 724's are a little cheaper than the earlier models...but I've got an early model.

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## orangputeh (Nov 24, 2016)

nhwylee said:


> I ordered the axle; I'll put the old one on fleabay if it is not worn when compared to the new one. The two gears were almost as much as the gear set with the axle so buying the gears alone didn't make sense. The individual gears and shaft for later model 724's are a little cheaper than the earlier models...but I've got an early model.
> 
> Sent from my Pixel 3 XL using Tapatalk


that makes sense. good luck. I'd keep the old axle if it's good. you never know.


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## contender (Jan 18, 2018)

nhwylee, I believe Jnc is too modest to suggest to you, but he has a excellent post on repairing the right transmission, that I have used many times on your same repair. He has also suggested the addition of a grease fitting which is very simple to do when its all apart and will add life to your machine. The post is the first posting under the Honda section.


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## nhwylee (Dec 7, 2018)

Old and new parts side by side. I thought the change in number of teeth was a ratio change reducing the torque on the final drive shaft but the gears are the same diameter. The gear pitch is coarser which accounts for the change in tooth count.


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## Prime (Jan 11, 2014)

The original axle is as good as a new one if its not scored. A cleanup with a wire wheel or emery cloth so the new parts slide on and your good to go. I would install the original and keep the new one as a spare. If you never need it. You have a new part you can sell down the road after your snow blowing days are done or you upgrade to a newer machine.


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## mfrs2000 (Dec 1, 2014)

Prime said:


> The original axle is as good as a new one if its not scored. A cleanup with a wire wheel or emery cloth so the new parts slide on and your good to go. I would install the original and keep the new one as a spare. If you never need it. You have a new part you can sell down the road after your snow blowing days are done or you upgrade to a newer machine.


That axle looks well worn to me. I think that where the bearings run it would be very sloppy. I would be tossing it and putting it together with the new one while its apart.


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## nhwylee (Dec 7, 2018)

mfrs2000 said:


> That axle looks well worn to me. I think that where the bearings run it would be very sloppy. I would be tossing it and putting it together with the new one while its apart.


When I took it apart, I wasn't sure if it was worn or by design, but compared to the new one it appears to be junk.

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