312-8 - Gear switching stiff and drain plug head slipping

[TC10284 111]

So I haven't posted in a while, because my family has grown in size and I've had to help take care of my son (born in November 2020), and now I have a daughter due in May. Plus, life has been busy in general, but I'm still trying to take some much needed time to spend working on my Horses.

 

Anyway, I've got a 312-8 that I'm fixing up. I had trouble getting it in gear after I got it running. I had to move it in neutral before I could get it in gear. I cannot get it in first gear no matter what, but I can get it in 2nd, 3rd, and reverse. Even then, I have to switch gears fast and somewhat hard. And sometime they still won't. 

It does move on its own and doesn't sound terrible. Reverse sounds kinda bad, but not too terrible. 

Switching started to get a bit better the more I switched gears and worked it. It had plenty of fluid, but it didn't look good. So I was going to try to drain it using the 1/4" alan head, but when I turn it, the bit slips and doesn't turn the plug. I tried the 1/4" bit on another WH transmission and it turned just fine. So then I tried a 7mm bit but that's too big. 6mm is too small. 

So I'm not sure what else I can do. I added some fresh 80-90w gear oil, but would really like to drain it all out. I haven't tried it since I added fresh. 

 

Does anyone have any suggestions here? 

Edited March 7, 2022 by TC10284

[daveoman1966 3,751]

If you are 'switching' gears on-the-fly, THAT is a NO NO.  Every gear you select MUST be from a standing STOP.  These are NOT synchromesh transmissions and on-the-fly gear shift is highly detrimental.  The whole shifting problem MAY be at the shift forks, which is adjusted by the DOG-POINT screw where the shift lever fits into the transmission.  Have a look at this pic...may help.  

[TC10284 111]

Thanks for this. I'll check the dog-point screw. 

Also, I never, ever switch while moving. Only at a standstill. What I meant there was that sometimes I've had to "rock" the tractor (and some others I own) back and forth sometimes using my bodyweight to get it to go into gear more easily. 

Edited March 7, 2022 by TC10284

[WHX?? 48,815]

Late congrats on your son & early 'grats on your daughter! 

Sounds like a PO has the allen plug rounded out so your best bet might be to try and get an easy out at it.  Another option might be to use a sacrificial allen wrench and custom grinding it to fit. It's a long shot but I got lucky like that once. 

Guessing you cleaned any dirt out of it to get the wrench to fully seat? 

Sounds like you have some binding on the shift rails and possibly need to flush it. Do not add any more lube till we can get the drain plug out. 

[953 nut 55,228]

9 minutes ago, WHX?? said:

plug rounded out so your best bet might be to try and get an easy out at it.  Another option might be to use a sacrificial allen wrench and custom grinding it to fit.

Another option that has worked well for many of us is to use a torques bit (don't remember the size) that can be driven into the rounded out allen wrench hole.      

[Handy Don 12,218]

1 hour ago, 953 nut said:

Another option that has worked well for many of us is to use a torques bit (don't remember the size) that can be driven into the rounded out allen wrench hole.      

Somehow I've acquired a small box filled with odd hex driver bits and tried this on a stuck pulley. It worked for one set screw, the other was just a blob of rust. Carefully drilled that one out (had to get a longer drill bit--jobber length didn't reach) and then chased out the threads.

[Pullstart 62,864]

12 hours ago, WHX?? said:

Do not add any more lube till we can get the drain plug out. 

+1 for the torx bit tapped into the rounded plug hole.  The tapping should help to shock the threads loose also.  If the torx doesn’t work, just drive that 7 mm in there with carefully strategerized taps and it should grab ahold. As for lube capacity, filling it right up to the tippy top with diesel or kerosene might help soak whatever’s binding that first gear… 

[peter lena 8,625]

@TC10284 while i agree with others on the , attempted drain plug removal ,EASY OUT REMOVAL , fittings are made for that . another thing , your rough attempt of gear slide , can only be helped with total drainage  / flushing and drive around , you could also jack it up on stands , so it could run with a flushing agent , like diesel / kerosene or atf fluid . this will not be a 1 and done , flush , my experience with drain and flush refill , is usually  2 times , hope fully as it loosens up , you will be able to  use every gear and hi / lo range , to increase  the flushing effect , also replace the shift boot , water typically destroys that .  I  replace my trans oil  , every other year , making it simple , wish you luck with your issue , pete 

[rmaynard 15,458]

Is it that the gears are grinding and won't let you "won't go in gear"? 

You must have the belt guard on in order for the drive belt to stop when the clutch is depressed.

 

 

 

 

Edited March 7, 2022 by rmaynard

[TC10284 111]

6 hours ago, rmaynard said:

Is it that the gears are grinding and won't let you "won't go in gear"? 

You must have the belt guard on in order for the drive belt to stop when the clutch is depressed.

 

 

 

 

 

The gears don't grind. I just can't switch to them (sometimes, without extra effort). I hear no noise whatsoever from the transmission when I try to switch. 

The belt guard is on also. 

Edited March 8, 2022 by TC10284

[oliver2-44 9,749]

I’m wondering if your shift rails are rusty or your shift detention spring is broken making it hard for the shift rails to move

[peter lena 8,625]

@TC10284  reading your issue ,  is all the related linkage , clear and free moving ? thinking , jim  above could be on to something . if ant part of that linkage is stiff or binding , or spring return is hesitant , it will affect function . last trans oil change ? ,  if those idler pulleys  start to bind and fail , can easily stop easy shifting . pete