Bolens G174: input shaft spline

   / Bolens G174: input shaft spline #1  

Rod in Forfar

Platinum Member
Joined
Apr 10, 2010
Messages
572
Location
Forfar, Ontario, Canada
Tractor
1960 Massey Ferguson 35 (Perkins), 1995 TAFE 35DI, 1980 Bolens G174, 2005 Kubota B7510, 2020 Kioti Mechron 2200ps UTV Troy-Bilt Horse 2 1988 Case IH 255 4WD with loader and cab
They don't break if you don't use 'em.

Yesterday the Bolens G174 hauled several loads of hardwood blocks out of rough terrain in the woodlot and dumped them in the yard for splitting. The Kubota B7510 with its remote works very well on the 3 pt. hitch splitter, btw.

Today as I pulled away from the shed with the dump trailer in tow, something started making a loud, scratching noise in the tunnel between the clutch and the transmission, and the tractor wouldn't move. I immediately associated the new fault with the hydraulic work I'd done last week, or with the Asian dump trailer.

Turned out it was a stripped spline boss on the input shaft. That's a female version of the input shaft spline, a piece of aluminum with two 5/32 spring pins through it.

An entertaining afternoon on the floor of the shop eventually led me to that conclusion. An Allen wrench slid through the pin holding one end of the spline boss allowed everything to turn properly again. But either the spline or the boss must be stripped for the input shaft to spin, so replacing the pin likely won't do.

Now I'm at the parts-acquisition stage: Does anybody know how many splines are on an input shaft? Are these a standard item, or Iseki-specific? Anybody have a source for the boss and the spring pins? Any suggestions as to how to get the broken pin out of there?

Thanks, Rod
 
   / Bolens G174: input shaft spline #2  
I had that problem with my G154. I bought a new spline boss $120
and the input shaft was stripped also. I welded the input shaft
along each spline and re-splined the shaft with my dremel.
here is a video of some of the details. You'll have to
split tractor to get the old spline boss out.


Bolens/Iseki Clutch Problems. G154 / TX1300F - YouTube
 
   / Bolens G174: input shaft spline
  • Thread Starter
#3  
I had that problem with my G154. I bought a new spline boss $120
and the input shaft was stripped also. I welded the input shaft
along each spline and re-splined the shaft with my dremel.
here is a video of some of the details. You'll have to
split tractor to get the old spline boss out.


Bolens/Iseki Clutch Problems. G154 / TX1300F - YouTube

That's a terrific video for someone like me who doesn't know what the inside of a tractor looks like. Somehow the parts diagrams don't make much sense on the page, but when I see the thing opened up on screen I have a much better idea of what I'm getting into.

So it looks as though I'm in for a tractor-split in the near future.

The lesson for me is that the Bolens G174 isn't supposed to do the kind of pulling a full-sized tractor does. Mine has run the pto for hundreds of hours over three years mowing and bush hogging, but one hour with small dump trailer with a few hundred pounds of firewood on it over rough terrain, and it's spline-boss repair time.

Oh well, the Massey Harris 30 has been feeling neglected lately, and it starts better in winter. No hydraulics, though.
 
   / Bolens G174: input shaft spline #4  
Any time the tractor is running and doing anything like just driving or mowing
or bush hogging that spline boss is working. Just pulling the dump trailer
did not in its self wreck the spline boss.
 
   / Bolens G174: input shaft spline #5  
Intetesting video. Looks like someone buggered things up pretty good in the past. I agree that it was only chance when that break finally occurred. What you were doing at the moment likely had little bearing on it.
 
   / Bolens G174: input shaft spline #6  
I was gifted a G174 because of that problem, old owner didn't wanna throw any money into it so gave it too me.

Back in 2011 before my neighbor gave me the tracter I looked into buying a new (old stock?) input shaft and spline boss from japanesetractorparts.com, the input shaft was $361.00 and spline boss was $131.00, not sure what todays prices are but will find out this spring when I order them myself.

If you got an allen wrench through the holes it's possible the spring pin was lost some time ago like what happened to mine.
 
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   / Bolens G174: input shaft spline
  • Thread Starter
#7  
I was gifted a G174 because of that problem, old owner didn't wanna throw any money into it so gave it too me.

Back in 2011 before my neighbor gave me the tracter I looked into buying a new (old stock?) input shaft and spline boss from japanesetractorparts.com, the input shaft was $361.00 and spline boss was $131.00, not sure what todays prices are but will find out this spring when I order them myself.

If you got an allen wrench through the holes it's possible the spring pin was lost some time ago like what happened to mine.

The pin sheared off when the teeth on the spline boss failed. I had to drive the centre of it out before I could reassemble the unit.

How do you know you need the input shaft? I think the spline boss is a bit softer than the shafts. In my case it was the rear half which failed and the boss was nearly smooth but there was enough left of the teeth on the shaft to the transaxle to hold well and likely for some time. The spllne boss and two pins I bought from Sonny's Bolens ended up costing about $160 with shipping and exchange. I think it started at $131.00. Interestingly, one of the pins we took out to disassemble the front drive shaft was the wrong size, likely 1/8" rather than the required 5/32".

Remember to wire the pins as you go on reassembly. There's no room to do the spline boss pins retroactively.

Rod
 
   / Bolens G174: input shaft spline #8  
The pin sheared off when the teeth on the spline boss failed. I had to drive the centre of it out before I could reassemble the unit.

How do you know you need the input shaft? I think the spline boss is a bit softer than the shafts. In my case it was the rear half which failed and the boss was nearly smooth but there was enough left of the teeth on the shaft to the transaxle to hold well and likely for some time. The spllne boss and two pins I bought from Sonny's Bolens ended up costing about $160 with shipping and exchange. I think it started at $131.00. Interestingly, one of the pins we took out to disassemble the front drive shaft was the wrong size, likely 1/8" rather than the required 5/32".

Remember to wire the pins as you go on reassembly. There's no room to do the spline boss pins retroactively.

Rod

When the tractor failed back 4 or so years ago my neighbor talked me into towing it to my place to see what was wrong, I had to remove the front driveshaft to get a good look at what was going on and noticed the input shaft was almost wore smooth and assumed the spline boss was just as bad. I told my neighbor how much the parts would cost and he balked for a few years then his daughter bought him a new compact John Deere then I was gifted the Bolens.

All the wires were still in place on my spring clips but the one that was missing then failed as there was no remnants of a spring clip in the input shaft.

I haven't broke my tractor apart yet as I was hoping I could get by cheap till I had time to fix it properly. I welded the input shaft and spline boss together and it lasted most of the summer, I moved to a large farm about mid summer and 17 or so acres by the house wasn't mowed in over a year and my weld failed while attempting to mow what was closest to the house, 3 foot or taller grass and going up a steep hill was more than the weld could handle, if I would have broken it apart to get a better grind and weld I feel it may have lasted, not much room in that tunnel to get a good grind or the tip of my mig into.

The tip of the input shaft broken off with the weld so I threw a few small stitch welds on so I can move it around under it's own power, not going to risk possible damage by re-welding it so will fix it right next spring, I'll probably sell the Bolens after I fix it as I need a bigger tractor where I live now.
 
   / Bolens G174: input shaft spline #9  
How many hours on these when failure happened?
 
   / Bolens G174: input shaft spline #10  
How many hours on these when failure happened?

The one gifted to me was used every summer for around 20 years to mow 2 fields, one around 4 acres the other around 8, hour meter stopped working long ago so I would think a couple thousand maybe.?

Mine was cared for very well though, oil changed every spring, always lubed, the implements wasn't so lucky except for the mower deck, it was used the most so was well maintained.
 
 
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