Weird Transmission Problem

Shawn R.

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I have an old Craftsman riding mower with an automatic transmission. What happens is, it'll run great at full speed for about 15-20 minutes, but then the speed would gradually begin to decrease. Up until it's running at walking speed. I can try to set it back into high gear but it just won't stay there. And the more I try, the slower it runs. Up until the point where it stops moving completely. When this happens, none of the gears work. But if I were to shut it off for about 10 minutes or so, and then fire it back up in high gear, it'll start working again but for a shorter time. I'm not really sure what to make of this. Has anyone elase experienced this problem?
 

bertsmobile1

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Time for new belts
It would be real helpful if you posted the craftsman numbers from the tag under the seat
There were a lot of old Craftsman mowers, made by near a dozen different companies with even more transmissions.
 

Shawn R.

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Time for new belts
It would be real helpful if you posted the craftsman numbers from the tag under the seat
There were a lot of old Craftsman mowers, made by near a dozen different companies with even more transmissions.

I'll get you the numbers when I have time.
 

Shawn R.

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As promised. Here are the serials from beneath the seat.

Mower.jpg
Seat A.jpg
Seat B.jpg
 

Shawn R.

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I still haven't found a solution to this problem. I know the mower is dirt old but it does still run. I guess it needs a transmission.
 

Rivets

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Did you replace the belts?
 

Shawn R.

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Did you replace the belts?
Yes. I replaced the drive belt and the deck belt a few months ago. It didn't help though. I replaced them because they tore in half.
 

StarTech

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With this mower being right at 21 yrs old an oil change in the hydro might be needed. Manufactured July 24, 2001.
 

Shawn R.

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Doesn't it use oil as transmission fluid? I could probably try changing the oil.
 

Rivets

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If you’ve replaced the belts then I would check two things. First, the next time it happens stop the unit and check the belt tension, belt should still be tight if the tensioner arm is doing its job. If the belt is tight I’m leaning toward worn pulleys, any one or combination of all three, idler, tranny or stack. With a twenty year old unit they could definitely cause this problem
 
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