Lift arms

[stray]

I lifted about 2 tons of moss out of my ponds last night. at the end of the session i kept hearing a swaking sound. This morning as i was greasing the center toggle and i saw grease coming out of a farily long crack in the center. Here the proble lay. I hooked up the buzz box and welded the centers back. I have heard some of you all have had this trouble. if mine gets any worse I'll be redesigning and re fabricating it.

 

[pajoube]

I ended up sending the center pivot pin back to PowerTrac and they beefed it up and I have not had a problem since.
Mine cracked when using the mini hoe in a major project.
PJ

 

[KentT]

Could we see some pics of exactly where the crack was? Having just bought a mini-hoe, I'm concerned about where/how it is stressing the lift arms...

I'm just learning how to use it, and wondering what is the least stressful way to get the job done... and what areas to monitor for signs of stress.

 

[pajoube]

Kent,
A little background. I noticed when using the mini hoe that the pivot center pin was starting to leak grease on one end (not the middle). I kept using the mini hoe on a major project but called a welder to weld the crack on the end. This helped for some time but again after using the mini hoe for a number of hours that this time I was gettiing grease out of both ends of the center pivot pin.
As I was unable to get the pin out, I sent the entire lift arm assembly to Tazewell and they repaired with a heavier center pin and so far I have not had any problems.
PJ

 

[pajoube]

Shows broken center pivot pin, both sides.
PJ

 

[pajoube]

Close up of one crack.
PJ

 

[pajoube]

Final shot of other side.
PJ

 

[stray]

Yes, That is where mine was starting to giveway before i welded it. Some time when you get time send us some pics of PT's repair. All i did was reweld with several passes. I guess we'll see later on how long my repair works.

 

[FOURTEEN]

<font color="red"> /forums/images/graemlins/blush.gif Same failure!

Not a difficult repair! You can grind out the old pin, but have a good welding shop properly weld the new pin into place!

Power Trac has beefed up the toggle!

Check out my repair at PT-425 PROS & cons?? #584022 - 02/12/05 !! </font>

/forums/images/graemlins/cool.gif

 

[KentT]

Thanks, PJ. Those are quite helpful, since I now know what areas to keep an eye on...

A failure like that would certainly put you out of commission for a few days!

As I said, I'm just learning to use the mini-hoe, and one of the "good habits" I'm trying to build is using the bucket curl for digging, and not really using the downforce of the lift arms for pushing the bucket into the ground. I'm still trying to understand the best "setting" for the tilt -- other than tilted enough to see the bucket underneath the QA plate.

I have found that a little tilt of the hoe downward at the same time I curl the bucket seems to work well to fill the bucket -- kind of a scooping action toward the machine. But, I wonder what stress this is putting on that pivot pin...

 

[J_J]

I hope you were careful to not penetrate to far with your weld bead.

I had to replace mine on my 1445 because of binding or rusting together. It was easy to grind out the old welds, and cut the 2 in pin on either side.

Here is a picture of the old pin and roll over sleeve.

 

[J_J]

Here is a picture of the new pin and sleeve.

 

[stray]

""I hope you were careful to not penetrate to far with your weld bead.""
Thanks JJ for the info and the pics. and 14 as well. Good pics both of you.
I was concerned about binding the rod and kept working the pivot each time I made a weld. As said we will just see how long it holds. I may weld a few short pieces in place for structure. If it needs to be done I will cut it out and rebuild the whole thing.

 

[stray]

Thanks PJ. Good pics of what looks to be a fairly common problem.
Mine wasn't that bad or I would have had to redo the whole thing. I guess I was lucky when I saw the grease squirting out the break.

 

[pajoube]

When curling the bucket tap the reverse peddle at the same time. This combination will give you the best action.
PJ

 

[pajoube]

The new mini hoes have the heavier center pins so I don't think they will have any problems.
One can put tremendous pressure on the pivot pin if the operator is unfamiliar. Curling the bucket at the same time as applying reverse will give you the best results. Applying pressure on the lift arms (downward) at the time of bucket curling will put the most pressure on the pivot pin, at least from my experience.
If you find a crack and get it welded right away you probably should be ok.
PJ