T-20 no reverse on 1 side

[racerone3]

got the hustler running tonight and with the machine up on blocks, started running everything through it's paces. found that reverse doesn't work on the right side. adjusted all the plungers, still no go. took out the diamond shifter and the pin was worn, flipped it over and tried again... still no go. normally at this point i would be thinking band/ drum failure except it has braking on the right side when the trans is in forward. is it a pretty safe guess that the teeth are stripped off the gear selector in the trans? seems like the only logical thing it could be to me, but it's one i've never heard of. I'm going to pull the trans next week when i get home from Ashtabula unless someone can think of something i might be missing

[LarryW]

With the diamond shifter out and you manually move the shifter collar in the trans with a screwdriver does it seem to do anything? Seems strange to have the diamond pin and something else wrong. I was just thinking, band/drum and pin failure are really the only thing I have heard of. Oh, oblong diamond shifter hole too but never any gear teeth problems? Hopefully something simple!!! Good luck with it.

[racerone3]

i used a screwdriver to move the shift selector while i had the diamond out, but didn't think to try running it like that. if i get any time to work on it tomorrow, i'll pop it back out and give that a try. forgot to mention that with the diamond in reverse, and the engine running, if you pull back on the right stick you can feel a slight pulsation in the stick. sort of like you would feel if you were trying to get one into reverse with the sticks pulled back, but not nearly as strong.

[Mike]

Pull the diamond shifter back out and use a screwdriver to carefully put the shifter into reverse manually. Then you can be 100% sure it is completely in gear. Good luck and let's hope for the best.

Edit: Man, I'm slow

[racerone3]

just drug myself back out to the shop and pulled the diamond shifter again. shifted to all positions with a screwdriver. the selector seems to work about the same as all other t-20's i've done this with. detent spring seems good. moved the selector into reverse and fired it up... still no go. i'll have to find time to pull/ tear down the trans tomorrow or it will drive me nuts wondering for a week till i get home from Ohio

[LarryW]

You sound like me. When something is broke. It has to be addressed NOW!!!

[racerone3]

Minor Carnage!
got the trany out and split the case... just as i suspected. all the teeth are missing from the inside of the outer drum the only spare 18 tooth drums i have have been machined 15 thousandths. they were going to go into a spare trany with new bands. looks like i need to source a new drum.
glad i pulled it apart anyway... the bands are on their last legs. i had planned to rebuild the trans in the Wild Wolf the next time i had money, but now i'll probably do this one first. the wolf still seems to be doing ok (said while knocking on wood, and with fingers crossed!)

You sound like me. When something is broke. It has to be addressed NOW!!!

your 100% right Larry, this would have ate at me all weekend!

[hydromike]

FRAGGED!

Oh man, that's rough. I don't know how many 18 toofed outers I have, but if I find one that's in decent shape, I'll bring it down for ya...

~m

EDIT:

just drug myself

just before the drive to Ash? Man, you Carolina boys start early...

[Don]

Ouch! 'Never seen one quite that bad. I don't think I have any more outers, but I'll check before we leave for Pine Lake.

Okay, somebody that knows these things well explain how he had braking on the right side in forward gear. I can't follow the power line through the trans (without the teeth on drum) and come up with anything reasonable. Are you sure there was braking on that side, Brian?

[hydromike]

good point... all I can come up with is that the gear selector wasn't fully moved over, and the braking was actually being accomplished by the adjacent drum/band.

maybe?

~m

[Don]

Well..... wouldn't the sticks still be working in the reverse mode and therefore realease the band tension on that drum? Thanks a lot, now my head hurts!

I'm going to go with the theory that the lack of drive on that side mimicked the feel of braking and that R13 was on the right track when he mentioned that he needed his "head checked" It's not a problem, Brian- that's why you fit in so well with the rest of us.

[racerone3]

with it in forward, the gear selector teeth are engaged to the plate between the planetarys. one drum turns backward, the plate and other drum turn forward. when you push the sticks forward, the forward band stops the one turning backward. gear selector/ output shaft turn forward.
when selector is in reverse, the selector teeth are (or in my case should be) engaged to the teeth in the drum. that drum (should) turn forward, while the other drum and plate between them turn backward. when you pull the sticks back it (should) stop the drum turning forward, forcing the other drum, and gear selector/ output shaft to turn backward.
when the selector is in neutral it isn't engaged to the drum or plate, so the drums can do whatever they want and the selector/ output won't do a thing.
with all the teeth stripped out of the drum, it was just acting like a second neutral. i believe if the plate between the gears had been stripped, then it would have had reverse and no forward. (and that i'd already have it back in the machine being tested... i have plenty of those plates laying around...)

not sure if that makes any sense the way i've written it, but it's all clear in my head

You are Right that I need to get my head checked Don!

[Don]

You're right, of course. That's what I get for trying to follow the flow of power without the parts in front of me and using my head instead! You always use both drums, bot only one set of drive teeth at a time and the power flows through the planetaries in either direction. 'shoulda knew that without the parts in front of me.

[racerone3]

no biggie! i had to go out and put parts together to follow the flow of power. i can usually see how most things work if i have the parts in my hand!

While were on the subject of trany parts/ rebuild... when ever you get a chance could you resend me the part #'s for the seals on the T-20? i had all kinds of good info on the old computer, and that was in one of the files i lost when the hard drive crashed. plunger O-rings are #30 right?

[Don]

The input shaft seal is SKF #9878 and the output seals are #17184. Motion sells them fairly cheap. I'm not sure of the O-rings: the old guy in the hardware store is so used to me buying the same ones, he just asks if I want the big ones or the little ones (diamond shifter and plunger seals). #30 sounds familiar for the plungers, but I can't say for sure.