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Old 04-02-2018, 10:26 PM   #1
City: Seattle
Join Date: Apr 2018
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MG502 driveshaft end play

Looking for advice here. One of my Twin Disc MG502 gearboxes has about 1/16" of play at the driveshaft. In other words, if you apply axial force to the shaft, it moves in and out of the gearbox. The play is in the gearbox, not in a coupler, u-joint, etc. The other has no play at all. Here are my questions: How serious is this? Can I continue running without causing additional damage? What would have caused this, or is it within the tolerance specification and perfectly normal? Thanks in advance for the help.

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Old 04-03-2018, 05:24 AM   #2
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City: Fort Myers, FL... Summers in Crisfield, MD
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I can't answer your question as to what the allowable tolerance is. However you might consider sending an oil sample off for analysis to look for elevated levels of metals. Also, some transmissions have filter screens and / or magnets in the drain plug. Might be worth researching and checking either of those.


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Old 04-03-2018, 10:12 AM   #3
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Call a Twin Disc dealer and ask him the specs if you don't have a manual. There will be some limits.
Don't believe everything that you think.
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Old 04-03-2018, 11:20 AM   #4
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Should be zero play in output flange.

Don't bother with an oil sample, you have an already confirmed problem.

Check drawing for the gear, some have a central nut/bolt that secures the flange. Bolt might have come loose.
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Old 04-08-2018, 08:50 PM   #5
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City: Seattle
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Give Mill Log a call. They are local here. I've chatted with the service guy in Kent Wa. Was a Huge help. 18547 E Valley Hwy, Kent, WA 98032 · (425) 251-3434. There should be no end play.
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