first gear pops out

[Bach-Ed 170]

I have an 857 and I believe it has a 5052 tranny.  I rebuilt it a year ago.  I was mowing today and it would pop out of first gear.  I know third gear pop out is rather common but first?  I was mowing and as I have a rather small hilly yard I mow most of it in first.  I've mowed with it and plowed snow and no problem until today.  If I kept my hand on the shifter it stayed in place and no complaint from the machine.  It seems to be fine in reverse and second, I didn't try third.  What's happening?

[953 nut 55,700]

I don't know that this is the problem, but I would start by checking the set screw that holds the sifter lever in place, could be backing off

[Terry M-(Moderator) 2,176]

That has the 5053 unidrive....My first guess would be the same.   maybe something to do with the shifter, detent balls or spring.

[Bach-Ed 170]

I'll give that a try tomorrow morning!

[Bach-Ed 170]

Nice idea, but no.  It tried it in reverse, second and third without problem.  But first even when just driving (nothing else engaged) it pops out in twenty - thirty seconds.

[stevasaurus 22,841]

OK...this post may get a little involved.  These transmissions do not usually pop out of 1st gear.  Yes, if the transmission is on there that came with that horse, it is a Wheel Horse #5053.  That means that it is a 3 speed uni-drive with a 4 pinion differential and 1" axles.  Before you end up dropping the tranny, we want to check out the shifter.  Does it seem sloppy??  You may want to pull it out and check that the whole bottom of the shifter is OK.  It will have a ball at the end of the shaft that engages and moves the shift forks into positions.  Also, the dog point set screw that engages the shifter ball has to be locked into the hole in the shift ball...snug but not tight.  Check this thread...
http://www.wheelhorseforum.com/topic/16582-help-my-shift-lever-pulled-out/
If the above does not fix your issue, you are going to have to open the trans.  OK...now I am guessing here...kind of. ..
What could cause this from the inside...
  1.  a worn cluster shaft gear...especially on the top end where 1st gear engages
  2.  a worn fork gear that engages both 1st and reverse...this is possible because the top part of the fork gear engages 1st and if the bottom part of that fork gear is OK...it will not pop out of reverse.
  3.  a bad bearing on the top (1st gear end...left side of trans) of the fork gear shaft that would put enough slack in the shaft to let the gear pop out.
  4.  It is possible that you may have a bad bearing on the left hand side of the cluster gear shaft, but I doubt it would just affect the 1st gear.  The rest of the transmission...ie...differential, mushroom gear would not cause that issue you have.  They are OK.

Do you hear any noises...grindings...howls...etc??  Anything new happening that was not there 2 weeks ago??  If not, my guess is that it is the shifter being sloppy and not engaging the gear all the way.  However, if you are using 1st gear all the time and then going into reverse with out coming to a complete stop (check the manual) you may have been grinding the edges of the cluster gear, and the respecting fork gear though the years, and you need a better one at this point.    Do the outside observations first...only you know how you have been using...or abusing this horse.  It is fixable...let us know. 


 

Edited August 8, 2015 by stevasaurus

[Bach-Ed 170]

Well I removed the shift lever and the set screw.  I took some photos and re installed the lever.  I got the set screw turned in until the shift lever wouldn't move then backed it off so it was free to move.  I took it out for a ride and still have the problem.  Since I have never heard anybody on this forum camplain of too many photos, here are some.  I don't know how well it shows but there is a flat that can be felt on the side of the ball.  What's next?

[stevasaurus 22,841]

Excellent pictures.  Try this...I think I see part of one of the forks chewed up a little also in your 1st  2 photos.  Take the shifter back out and use a long screw driver or punch to slide the fork into first gear by hand and then take it for a ride and see if it pops out.  This will tell you if it is your shifter along with the face on the fork that may not be engaging the gear all the way.  The left hand fork in your picture...you want to slide that down to be in 1st gear.  The left fork is 1st and reverse, and slides the fork gear in either direction on the spline shaft to engage the desired gear.  Your pictures show your transmission in neutral. 

[Bach-Ed 170]

I went out this morning and tried to do what you suggested.  But the seat pan extends over the shifter opening so a straight item can't reach in there.  I know a lot of you have much more experience than me but I can't figure a way to put it in first and then starting the engine or getting it in gear with a screwdriver while seated and depressing the clutch/brake.  Is it time to try and find a shifter in good condition and see what that will do?  Ot bite the bullet and get a shifter and open it up (which would be nice to avoid) so I can install another fork also?

[Racinbob 11,179]

Bach-Ed, there's spring loaded detent balls that engage in grooves on the shifter rails when it's in gear. You can feel them when you shift into gear. Try going through each gear with the motor not running and see what each gear feels like.

[stevasaurus 22,841]

You should not have safety switches on the 857.  You should be able to put it into 1st gear...close the seat...climb on and push in the clutch and start it...let out the clutch and take it for a ride.    Can you see the face of the fork that I am talking about??  Is it just the light from the camera that makes it look chewed up?   You could weld a little material on the ball of that shifter and then grind it to be correct.
Do you have pictures of the gears from when you rebuilt it??  I don't think it is the detente balls and spring if you can shift it into the other 3 gears and it feels OK shifting.

Edited August 11, 2015 by stevasaurus

[Coadster32 793]

I agree with Stevasaurus. Try to get it going without the shift handle. If it runs ok without popping out of gear, than you can rule out opening up the tranny. It looks like the ball on your shifter handle might have a bit of a flat on it...possibly causing the slip out issue you are experiencing. (My tranny problem was a worn shift fork back in the day) Good pictures, and they do help. It'd be worth moving the seat out of the way if needed to try this.

[Racinbob 11,179]

I agree as well and you should try that test. Here's my thoughts on seeing if you can feel it 'lock' in to the detents in all gears. The shifter has the ability to actually move the forks past the detents but it doesn't because the gears physically stop it. The shifter doesn't do a thing to keep the transmission in a particular gear, the detents do. By moving through the gears gently you will feel when the detent balls engage. If you feel them engage as you shift to first, the shifter got them where they belong. I also agree that the 1st/reverse fork looks suspect in the picture and it's the area the shifter contacts to put it in 1st gear.

[stevasaurus 22,841]

I'm hoping you took pictures of the gears when you rebuilt it.  That would save us a ton of speculation and narrowing things down.  Also, like Bob said, take a good feel of the shifter when shifting concerning those detente balls. 

[Bach-Ed 170]

I did take a bunch of photos but they are before pics.  I'll attach some and let you guys decide.  I won't be able to take it out for a test drive until this afternoon, I'm on my way to help out at my local food pantry.  That tranny wasn't too pretty when I took it apart.  It got all new seals and bearings.  Except for the 1533s, With a lot of work I managed to get them cleaned up and working.

[stevasaurus 22,841]

Ed, I've done a couple of transmissions that looked that bad.  It is a real feeling of accomplishment to take a trans like that and get it to where it runs again.  Great pictures...thanks.    In your bottom pictures, the larger fork gear is your 1st and reverse...the teeth on the gear, away from the groove are the teeth that engage with 1st gear.  I am trying to determine if those teeth are worn from your pictures...actually, I think, they look like they are not bad.  There is some bevel there, but it doesn't look like it is enough to cause your problem.  With the cluster gear, not really a good look but, it looks like it is OK also.  We would want a good picture of the small gear end of that gear.  The fork gear would slide into the small gear end, from the inside, for 1st gear.  Even from what I can see of the forks, where the shift ball engages, looks OK.   At this point, I think it is your shifter.    Let's see what you say after you take it for a ride.  Thanks for the great pictures.

Edited August 12, 2015 by stevasaurus

[Bach-Ed 170]

Well we had a test drive today.  When using the screwdriver I did not feel a detent engage so...  But I put the seat down and away I went about twenty feet and it popped back to neutral.  unless someone has a easier idea I suppose it is time to remove the tranny.  Although I probably will hold the shifter and get one more mowing in.  O guess this is reason I need a second Wheelhorse, right?  Then I can take more pics.

[Racinbob 11,179]

It probably would be harder to feel the detents using a screwdriver. But, as long as you had the fork pushed all the way you were there. I'm thinking it's gonna have to be opened up. 

[stevasaurus 22,841]

Yes, I agree...open it.  By chance, did you look at those ball bearings when you had it open.  It is weird that you have used it OK for a while and then it happens.  I'm going to send you a PM with my phone number on it...I have some options that may interest you.  Give me a call if you want. 

Edited August 14, 2015 by stevasaurus

[Bach-Ed 170]

Well I opened it up and OUCH!  I took a bunch of photos and stopped.  I didn't want to get too far ahead of advice.

[Bach-Ed 170]

Well I lied or really couldn't stand the suspense.  I shifted the gear and removed the "top one" so you could see the match of these two.

[Racinbob 11,179]

Your 1st/reverse gear is toast. There's your problem.

Edited August 15, 2015 by Racinbob

[stevasaurus 22,841]

Yep...we found it...you need, at least, a 1st / reverse fork gear...WH # 5174.  I'm sure you did not put it back together like that...look for loose teeth.  The Wheel Horse Tooth Fairy (Mike...racinfool40) probably has a good used fork gear for that...put those loose teeth under your pillow and send Mike a PM.  The cluster gear looks OK...could replace the reverse idler.  Take some good pictures of all the gears...we are looking at the teeth.  I see at least one bearing you want to change out and you might as well do the seals.  After pictures, send a PM to Mike...you may have this back together in 2 weeks.    Guess what...it wasn't the detente balls.    Although, if you want to replace them...they are 1/4" ball bearings...ACE sells them one at a time for pennies.  Really want some good pics of that cluster gear...especially the gear at the small end.

Ed, it is a good thing that you opened up this trans when you did...you could have caused a lot more damage for sure. 

Edited August 15, 2015 by stevasaurus

[Bach-Ed 170]

You sure couldn't have seen this looking through the shifter hole.  I will pull all the gears & shafts out and clean very completely.  There are probably a lot of fine metal shavings present now.  Also the first gear detent still doesn't really click so we will see what we find there.  My six year old grandson "helped".  He did enjoy seeing how the gears moved.  Maybe we'll have more surprises tomorrow.  Thanks for all the great advice.

[Tuneup 1,433]

Your six year old is now a gear head in the making and that machine, when handed down to him, will mean much more than just some machine Dad loved. Great project! How the heck did that gear shear like that???