Series G info

[ruffdog]

Is that the keyway we are seeing at 10 oclock? Also, the grain is different at 2 oclock and at the bottom and top. Not uniform. At the far back is the hydraulic pump that can be separated from the 2 hydrostatic pump halves. I wonder if you would be able to just get the pulley half of the pump out?

 

[laurencen]

sure looks like the keyway, first looks I would say the shaft was not aligned causing stress but its a pulley, only thing is if the tension was way too high but sure is a odd looking break, some looks old fracture, could anything get trapped between the pump and pulley?

got a picture of the pully end

 

[oneal]

sure looks like the keyway, first looks I would say the shaft was not aligned causing stress but its a pulley,

Yes, the key and key way is in the pic.
The engine and pump bolt to a large casting with no alignment adjustment.

only thing is if the tension was way too high but sure is a odd looking

Tension is preset by the OEM spring tensioner. The only adjustment is to remove free play.

some looks old fracture

I agree, some of the fracture lines are not fresh.

could anything get trapped between the pump and pulley?

The entire drive system is encased with no way for objects to get into it to cause this.

 

[oneal]

With the current evidence of a shaft that had missed something in its build process like improper metal compound or heat treat I am now hopeful the shaft just finally and randomly come to the end of its life.
This would be much better than the shaft breaking due to internal failure and all the mess of a hydraulic system infiltrated with metal particles.

 

[laurencen]

My bet is alignment rather than bad heat treating when the shaft was made, just a little stress when in use over a few million revolutions, that way a fatigue crack develops and eventually lets go, look for a new shaft and seals and with luck the cab does not have to be removed, good luck with this one

 

[ruffdog]

I finally performed the hyd pump belt adjustment that was mentioned earlier. It was quite easy on the G series and only took 1.5 hours. Some of that time was welding a tailpipe bracket that broke. I found out that I didn't have to remove the muffler or large cover like the manual shows. Maybe they improved the process on the G? Remove the 5 bolts and remove the inner fender. Remove 3 bolts to remove the tailpipe. My tensioner gap was at 1/4" and it should be 1/8" MAX. They conveniently have openings in the belt cover to make the adjustment.

Edit: Parts and processes will be different even within the G-series. I'm seeing different part numbers depending on serial number.