Bent pivot pin

[pajoube]

MR, your correct about the layout of the pin. I have had mine welded on both sides and one has split open again. The welder came by today and will re-weld again. Most of my very heavy work is finished for now so will try and make due with the new weld. If all else fails, I will replace the pin and sleeve with heavier stock.
PJ

 

[FOURTEEN]

.



Talked to Terry. He said to ship the Lift Arms to Tazewell as soon as I can, and they would repair it.



.

/forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

 

[Tak]

Toy,

Terry told me the same thing about what caused my break, but I don't do that type of ramming motion. I don't think that cause he stated is correct. Wouldn't seem to produce enough of the compression force nec to do the damage. Seems like the damage would possibly occur

1) with the mini hoe fully extended and pushing down? (maybe not?) or even more likely
2) with the hoe up and retracted and reversing the pt with the bucket hooked on an ridgid item like a rock or stump

I'll eliminate #1 myself. I think it is #2

lt

 

[Tak]

mr,

Description - exactly correct

Pin WELDED to lift arms - poor design but probably a cost measure so understandable. If pin was "Pinned" to lift arms, Piece of cake to replace unless damage already occured.

If pin is already bent and/or sleeve broken, replacement of pin is not that easy to do. Pin must be cut out not only from lift arms but also from sleeve as it will not slide out of sleeve anymore. Not that fast of a repair.

Regarding rewelding a cracked sleeve, see my following response to pj.

Consider a reinforcement like mentioned before. 10x easier

lt

 

[Tak]

pj,

Sorry to not reply earlier regarding your post of rewelding the cracked sleeve. I got tied up.

I did notice the flaw in your repair description. The rewelding just repairs the damage done. However, the problem doesn't go away. It just moves the location where the next crack will occur outside of the reinforced weld area.


Agree, best bet to replace pin and sleeve.

Just a thought, as a second best option, consider reinforcing the pivot arms together distribute the load to the sleeve and pin more evenly.

lt

 

[pairodime]

It looks like everyone with damage to the pivot pin is a mini hoe user. Anyone not own a minihoe that has the problem?

 

[SnowRidge]

After following this thread for awhile, yesterday I went out to the shop and took a careful look at the pivot area. I don't see any sign of a problem, incipient or otherwise. I don't own a mini-hoe, but have been thinking about getting one.

Now I'm not so sure.

SnowRidge

 

[SnowRidge]

Further thought. When we took the service training from Terry, I recall him mentioning how critical it was to grease that pivot point. He then said something like, "That part of the machine has more stress on it than any other part." He mentioned there had been some failures, and I think they had one in for repair at the time.

I believe he indicated that owners not following the lubrication schedule was the primary cause of the failures.

SnowRidge

 

[MossRoad]

I always grease everything at 8 hours or less. The pivot pin get grease until I see it coming out the ends. My guess is it isn't the grease, but the force on that area. Could be the weakest link, so to speak.

 

[toy]

I took mine in last thursday with a bent pin I beleive it was the 29 of April. I hope he was not refering to mine as not being serviced regular. Since the 8 hr service only takes a few minutes I service mineeven more regular than the 8 hr schedule, but I also always service at the 8hr interval to make sure that I don't go over I want my machine to last a long time and am a fanatic about servicing it.. Mine only has 88 hrs on it, and I have had to change the oil and oil filters once.

 

[Tak]

sr,

minihoe - yes, I believe all the problems usually occur with that particular attachment's configuration. I'm definitely not as experienced as Terry, but I don't believe the lack of greasing is the problem (not in my case anyway). Not greasing could definitely make the problem worse but I don't think it's the primary cause.

See my previous post about what type of action causes the problem. I think the problem occurs because of how the pt is used.

For example, an excavator is basically stationary when performing its digging task. Operators don't usually move the machine backward while the bucket is digging.

Whereas, that pt is "efficient" at digging by moving the machine backwards while digging. If the bucket engages a relatively stationary object, there is a tremendous amount of force placed on the pivot assembly. The tie rod from the attachment plate to the pivot arm is in compression and may cause the tie rod to buckle also.

It is the position/geometry of the minihoe that causes the problem. The worst case position would be for the "dipper" part of the arm to be as perpendicular to the ground as possible.

In other words, if the "dipper" part of the arm was even longer, the problem would be even worse.

Aside from any reinforcement or modification to the machine, I believe correct/proper operator usage as described above could prevent that type of damage.

lt

 

[SnowRidge]

</font><font color="blue" class="small">( I hope he was not refering to mine as not being serviced regular. )</font>

We were there in June of last year. The machine he was referring to predated that--by quite a bit, I believe.

SnowRidge

 

[pajoube]

I agree with you. Had another crack on a previous weld found this past week. I think I will call Terry and arrange for the fork to be sent to him.
PJ