AceDeuce
Gold Member
- Joined
- Mar 23, 2006
- Messages
- 346
- Location
- Northern Virginia
- Tractor
- Kubota BX1500 w/ R1's and LA181 FEL
So I'm going along and I suddenly hear a klunking sound coming from underneath the tractor. I stop, get off and look underneath. I find the front drive shaft dangling---this is new... The 1/4" X 1-1/2" roll pin that holds the universal joint to the shaft coming from the HST sheared off. I was able to remove the piece in the yoke but there is still a piece lodged in the drive shaft that I wasn't able to push out---need a different tool--- and a couple more elbows to reach up under there. It'll be fixed after a run to the hardware store.
The big question is... why? That roll pin should not have been taking any load. It is a splined shaft connection, so there should not be any torsional stress on the pin, and the other side of the universal joint has a telescoping splined shaft connection so there should not be any axial stress or moment on the u-joint. I can't imagine how the pin broke. Sorry for not posting any pics but it looks like fatigue cracking on both sides of the pin as it passes through the splined area between the shaft and the yoke. That would indicate play in the shaft but I couldn't feel any.
Anyone else had this problem? Should I replace it with another roll pin or something else? Not a big problem by any means but a pain in the neck (literally) nevertheless.
The big question is... why? That roll pin should not have been taking any load. It is a splined shaft connection, so there should not be any torsional stress on the pin, and the other side of the universal joint has a telescoping splined shaft connection so there should not be any axial stress or moment on the u-joint. I can't imagine how the pin broke. Sorry for not posting any pics but it looks like fatigue cracking on both sides of the pin as it passes through the splined area between the shaft and the yoke. That would indicate play in the shaft but I couldn't feel any.
Anyone else had this problem? Should I replace it with another roll pin or something else? Not a big problem by any means but a pain in the neck (literally) nevertheless.