ok, tell me if no or go

[groundhog47 347]

Sometime back I suggested placing a collar to "check"/cure axel drift,  well it drifts inward both sides with hub also. Maybe I turn too many circles. I took center line of key and ground an indent where set screw fits, this may cause an axel key shear  . Is this something anyone has tried before with success, or complete "no". Am goin out shortly to do some tight turns without implements first. Any help appreciated.

 

[Kelly 1,029]

Sounds like you need new hubs or the shafts are worn from running bad hubs. 

[groundhog47 347]

I really can't tell hub left extremely tight, needs puller. Hub right can kinda "bump" it off with not a tremendous force. I just reviewed key stock and parts list, which shows should be a 1/4"w x 1" long key. The one in axel appears tight and just a shiny spot where sits down in groove. I'll have to remeasure key. With laps around yard ccw and cw  and no implements didn't encounter drift. had set scew centered on groove ground in (center of key) which leaves axel inset 1/8" or so. I can't find where read it but thought axel was to be flushed with edge of hub which throws set screw to rear 1/3rd of key. After these 36 yrs of owning, having not had this probyou may be correct Kelly, but I would think should have more slop/play in hub. Thanks for input 

[stevasaurus 22,872]

Gerry, are your hubs actually moving on the axles, or are the axles moving in and out more then you think they should??  The axle is designed to move in and out a good 1/8".  The hubs should be flush with the end of the axles.  New keys are cheap and can be picked up at Tractor Supply or Ace or Toro.  I have had to grind or file a little on those keys to get a good fit with no problem. The set screw in the hub should have an indentation in the end of the bolt...concave...inward.  Toro has these, as does MacMaster-Carr.

[SousaKerry 502]

What tractor are you having problems with?  Most of mine have very little room if any between the hub and the end of the Transmission case.  A clamp collar or two may help but it is only a temporary fix.

[groundhog47 347]

Gerry, are your hubs actually moving on the axles, or are the axles moving in and out more then you think they should??  The axle is designed to move in and out a good 1/8".  The hubs should be flush with the end of the axles.  New keys are cheap and can be picked up at Tractor Supply or Ace or Toro.  I have had to grind or file a little on those keys to get a good fit with no problem. The set screw in the hub should have an indentation in the end of the bolt...concave...inward.  Toro has these, as does MacMaster-Carr.

The hubs drift in toward tran (total drift approx. 3/4"), the very center of key with set screw centered leaves 1/8" or so outset of hub (axel back approx. 1/8"). With hub and axel fush, set screw hits/fastens down on rear 1/3 of key. I ground a notch that set screw would go into (center of key stock), the indention on set screw is there but "smeared" a bit, dimple still there. Seems I saw where gear lube wetted axel and key may be a culprit also. Local auto parts out of #15 key and haven't made it to TSC today yet, but the keys fit tightly in groove, no wobble.

 

My main concern was key shear after groove grind weakened it. As soon as get new set of keys will wipe down axel good, put in new keys with chalk mark, put a new set screw in and see if my eyes were off on center. I'll prob go ahead and add the 90 degree off set set screw also.   Thanks

Edited July 25, 2013 by groundhog47

[groundhog47 347]

What tractor are you having problems with?  Most of mine have very little room if any between the hub and the end of the Transmission case.  A clamp collar or two may help but it is only a temporary fix.

It's a C-120 8 speed with approx. 3/4" clearance bet hub and housing. The collar didn't help, it drifted. Maybe I just ain't torqueing it down enough, but it's all I can get!! On the L-156, non running I put a washer, 90 degree set screw, but haven't got er runnin' yet and it had drifted with PO. Thanks 

[doc724 925]

If you used new keys and new "cup point" set screws and loctite blue on the set screw and jamb nut, they should not move.  I just did my C141 and no issues after 2 months.  Note, I only used a 3/8 wrench to tighten the set screw and it is difficlut to get enough torque.  Another RS member suggested to use a 3/8 square drive-12 point socket of a tbd size so you can develop more torque. 

 

PS: make sure you use good quality set screws since you dont want them to shear off inside the hubs. 

[groundhog47 347]

If you used new keys and new "cup point" set screws and loctite blue on the set screw and jamb nut, they should not move.  I just did my C141 and no issues after 2 months.  Note, I only used a 3/8 wrench to tighten the set screw and it is difficlut to get enough torque.  Another RS member suggested to use a 3/8 square drive-12 point socket of a tbd size so you can develop more torque. 

 

PS: make sure you use good quality set screws since you dont want them to shear off inside the hubs. 

Thanks will try that as soon as get all the goodies.

[Callen 64]

Just set it where it is supposed to be and tighten the set screw. Go make a few circles and tighten it again. Few more circles tighten it again then, lock the jam nut.

It is designed to lock on the inner third of the key so it will tilt the outer end of the key up. That will prevent the hub from sliding off the axle because the set screw won't go back over the key.

Any kind of foreign material in the key ways or threads for the setscrew will compact when tightened and will work out when moved leaving it loose again.

Edited July 25, 2013 by Callen

[Jeff-C175 7,203]

 

Another RS member suggested to use a 3/8 square drive-12 point socket of a tbd size so you can develop more torque.

 

I said something like that in one of my posts... but not a 12 point socket... purchase a 3/8" EIGHT point socket.

 

I tightened them set screws as tight as I could get them with an open end wrench and they kept coming loose.  Then I put the socket with the torque wrench on it and was amazed how loose they were with the open end.  You really need to torque them to the 30 ft-lb specification.  Hain't loosened up again...

 

I agree about adding the second setscrew 90° around.

[stevasaurus 22,872]

Please do not take any offense to this you guys.  I consider this an open debate and I am learning also.  My dealings with this leads me to like what Callen has said.  It looks like we are talking about the hubs here at this point.  I also agree with Jeffpicks with what he is saying about the torque thing.  I do not like the 90 degree drill hole, tap and add another set screw idea.  I know it has been talked about here before, and has worked and will work for these issues.  My problem is that once you do that (add a 90 degree set screw) you have taken the integrity of the wood ruff key out of the equation.  That key is meant to give way before you do damage to the internal gears in the transmission.  I think what you are trying to do is fix one problem,  bypassing the real cause, and creating a larger one which could end up in more damage and cost then fixing what is wrong in the first place.  Does that make any since??    I think if Gerry changes out the keys, and the set screws are not worn at the bottom...that should take care of it...see what happens and go from there.

[Don1977 604]

Please do not take any offense to this you guys.  I consider this an open debate and I am learning also.  My dealings with this leads me to like what Callen has said.  It looks like we are talking about the hubs here at this point.  I also agree with Jeffpicks with what he is saying about the torque thing.  I do not like the 90 degree drill hole, tap and add another set screw idea.  I know it has been talked about here before, and has worked and will work for these issues.  My problem is that once you do that (add a 90 degree set screw) you have taken the integrity of the wood ruff key out of the equation.  That key is meant to give way before you do damage to the internal gears in the transmission.  I think what you are trying to do is fix one problem,  bypassing the real cause, and creating a larger one which could end up in more damage and cost then fixing what is wrong in the first place.  Does that make any since??    I think if Gerry changes out the keys, and the set screws are not worn at the bottom...that should take care of it...see what happens and go from there.

I disagree I don't think you would ever shear an axle key. I have seen pictures on here where the key has worn the axle to double the key width. I believe in changing to a new keys and set screws every time you remove a hub. The slightest ware on the keys will let the hub move until it wares off the set screw and the key way in the hub, then you have the hub sliding when turning. The 90 degree set screw is a tried and true engineering fact, but it is not a cure for hubs that are too loose on the axle.  A good tight fitting hub is the only fix then the 90 degree set screw is good insurance to keep the hub fixed in place. If a hub moves you are waring all surfaces the interior of the hub, the key way, the key, the cup point of the set screws and the axle.  My experience has been with the use of a C-120 for 36 years. I had to rebuild my hubs as they got to the point that I could not keep them tight.

 

Here is a link to the rebuild:

 

[doc724 925]

Hi Jeffpicks.

 

I have never seen an 8 point socket. (although I admit I never looked for one)  I have 6 point and 12 point.  I did a quick search and I guess Sears (Craftsman) sells them.  I gather they have unique uses.  Thx

[Callen 64]

Doc,

They fit square nuts and some set screws on older farm equipment and some taps.

[pfrederi 17,887]

12 point sockets will work on square head bolts (just have to experiment to find the right size)

[Jeff-C175 7,203]

 

I gather they have unique uses.

 

Yes, as mentioned, square nuts and setscrews..

 

A 12 point socket MIGHT work... there would be three positions that a square can fit... the problem is going to be finding the right size socket.  A 3/8" 12 point socket will not fit a 3/8" square head.  You would have to find the right one by trying them, and even then you might not find one that fits...

 

Nor will a 12 point socket have the same 'grip' as an 8 point due to the geometry of the points.

 

I also 'debate' the fact that a woodruff key is intended to be a "shear point" in the system.

 

Wheel Horse started putting the two set screws BACK in themselves... and I believe that the earlier machines HAD two setscrews???  The fact that one setscrew was even attempted was probably a 'cost reducing' experiment.  When they started seeing the problems, they went back to dual setscrews. 

 

There is a service bulletin somewhere around here that shows that Wheel Horse themselves had instructed service centers to drill and tap hubs for a second setscrew for problems with loosening hubs.

 

One setscrew is not enough in any case (except very low torque applications) to luck any hub to any shaft.  ANY clearance between the hub and the shaft, even 0.001" and the hub will 'pivot' on the single point... slowly, every so slowly wearing a larger gap, until something is worn beyond repair.

 

I say that if a machine with single set screw hubs does NOT have worn and loose hubs, it is because the hub and axle have rusted together before they could wear out.

 

By adding the second setscrew, you are forming a 'triangle' of force... and a triangle is about as strong a structure as there is.

[groundhog47 347]

Just set it where it is supposed to be and tighten the set screw. Go make a few circles and tighten it again. Few more circles tighten it again then, lock the jam nut.

It is designed to lock on the inner third of the key so it will tilt the outer end of the key up. That will prevent the hub from sliding off the axle because the set screw won't go back over the key.

Any kind of foreign material in the key ways or threads for the setscrew will compact when tightened and will work out when moved leaving it loose again.

Ya know, that is a good point I didn't consider as a bit of gob and grease was on and in the slot. Maybe I created the problem, but don't remember greasing axel. I fig'd the tilt of key would cause hub to tend to drift inward. At any rate the hub had moved beyond set screw contact all together. Thanks to pacer Bill have new keys and thanks to specialwheelhorse Jim have new set screws. Now if I can just get groundhog47 Gerry to get busy we'll see what happens.

[specialwheelhorse 174]

Anyone working with Wheel Horse tractors go to your local Sears

spend a couple bucks and buy a 3/8th drive 8 point socket for 3/8th

# 44343 you won't need it often so put it where easily found.

I'm preaching to myself now !!!

[gwest_ca-(File Mod) 11,101]

After the set screw is torqued down just snug up the locknut. Any tighter and the nut tends to pull the set screw back out so you lose the torque you put on it. The 1978-79 service manual 810063R1 shows a hub set screw torque of 28-32 ft. lbs. on page 1-4.

 

Garry

[pfrederi 17,887]

After the set screw is torqued down just snug up the locknut. Any tighter and the nut tends to pull the set screw back out so you lose the torque you put on it. The 1978-79 service manual 810063R1 shows a hub set screw torque of 28-32 ft. lbs. on page 1-4.

 

Garry

 

If you opt to drill and tap a second hole follow Gary's advice about only snugging the lock nut. I snapped off a hardened set screw flush with the hub.  Hope I never have to take that hub off again!!  The factory machined a flat surface for the lock nut, the do it yourself one probably is not going to be perfectly aligned with the curvature of the hub hence it puts side stress on th set screw and if you tighten it too much...snap!!