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Technical => Dan Dishon's Transmission Den => Topic started by: 32bantam on December 13, 2015, 02:58:33 PM

Title: leaking sealat shift shaft
Post by: 32bantam on December 13, 2015, 02:58:33 PM

Hi Dan.......I'm asking this here because it may help someone else.
That shifter seal is still leaking in my trans. I have replaced it twice. Only leaks when fluid gets above the shaft.
So...do they make a "dual" seal or better quality? How about a speedi sleeve? I might be able to machine a thin sleeve for the shaft or maybe a o-ring? 
It never leaked until Hughes rebuilt it, so I'm at a loss as to what is going on.....
Thanks.
Merry Christmas

Title: Re: leaking sealat shift shaft
Post by: jeff/21 on December 13, 2015, 03:22:33 PM

the shaft might be loose in a worn case and leak when the trans is in park I have two trans that have to be repaired waiting to after Christmas to look at it should be able to sleeve the case

Title: Re: leaking sealat shift shaft
Post by: bikeguy307 on December 13, 2015, 05:39:27 PM

I'm wondering if it is leaking past the seal around the shaft, or around the seal at the case. If it's around the seal and seal with some sealant on it should help. Check the bore the seal rides in, maybe it was damaged when they removed a seal. A small gouge could be a path for fluid to leak. Some transmissions have an o-ring in the shaft bore. If a shop could go in the bore and cut a grove for an o-ring, that would keep most all the fluid from getting to the seal.

Title: Re: leaking sealat shift shaft
Post by: msundstrom on December 13, 2015, 09:14:10 PM

I have had the same leak issue before and machine a groove in the shaft for an o-ring and still keep the original shaft seal. Never had a leak since.
Mark S

Title: Re: leaking sealat shift shaft
Post by: bikeguy307 on December 14, 2015, 06:08:54 PM

It would be easier to o-ring the shaft, but I would be careful to not go over board with the size and compromise the strength of the shaft.

Title: Re: leaking sealat shift shaft
Post by: msundstrom on December 15, 2015, 12:05:39 PM

I considered that and checked the torque to shift in and out of park and gear to gear and had between 7 and 18 ft.lbs then cut a .040" o-ring groove in a shift shaft and held to 160 ft.lbs so I felt pretty safe . Probably won't work on a stock hollow shaft.
Mark S

Title: Re: leaking sealat shift shaft
Post by: bikeguy307 on December 15, 2015, 01:53:01 PM

Thanks, Mark. That's great info, and glad you did the research before just cutting into the shaft.