Bent pivot pin

   / Bent pivot pin #1  

Tak

Member
Joined
May 19, 2002
Messages
48
Location
Kaneohe, HI
Tractor
PT 422
FYI post to prevent others from experiencing this headache.

PT422. Pivot assembly that controls tilt of the attachment plate. Cylinder connected to bottom of assembly, connecting rod connected to top of assembly.

1-1/4" Pin located in sleeve bent and thus broke the sleeve between the arms. Pin needs to be ground out and replaced, sleeve needs to be rewelded. Not too major but a pain nevertheless.

Pin is only cold-rolled steel. Too weak.

Will be replacing with 4140 heat treated pin - will follow up post if any other issue pops up.

Terry @ PT confirmed it does happen although not very often (only a handful of cases - however, you don't want to be one of the handful)

GOOD PREVENTATIVE MEASURE BUT NO GUARANTEE: (Seriously consider this - it will save a lot of time and headache.)

2 Pivot arms - reinforce across arms with plate steel. Be careful to raise/lower arms and tilt attachment plate to note maximum tie rod and cylinder travel so your plates don't interfere with rod or cylinder.

Aloha
 
   / Bent pivot pin #2  
Not sure it this is what you are talking about. I had a problem with the weld and lost the seal for lubricating the lift arm.
PJ
 

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   / Bent pivot pin #3  
I ended up hiring a welder to weld both sides. Has worked perfect since then.
PJ
 

Attachments

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   / Bent pivot pin
  • Thread Starter
#4  
PJ,

No, not the same. Pivot assembly is about midway on the lifting arms and is welded to lifting arms.

lt
 
   / Bent pivot pin
  • Thread Starter
#5  
PJ,

Disregard my last post. I didn't see your attachment. Yes, we are talking about the same problem. Our pin was bent too severely. As mentioneded, pin will be replaced with stronger pin, will be rewelded and reinforced with plate steel. Never will happen to me again.

I would imagine your pin would bind a little as it would also probably been bent?

lt
 
   / Bent pivot pin #6  
It has a small bend to it but not bad as I caught the problem prior to it bending further.
What were you doing that caused the bend?
PJ
 
   / Bent pivot pin
  • Thread Starter
#7  
PJ,

We were pulling out a palm stump - tough buggers. Our sleeve is completely broken in 2 places at the same location as your photo. Those PT pistons are tough too. Too bad the pivot assembly wasn't as tough.

We are replacing the pin with a 4140 pin, replacing the sleeve with a larger diameter sleeve bored out to a standard size pin and reinforcing the pivot arm to sleeve connection.

Like I said before, this will not happen to us on this machine.

What were you doing to damage your assembly?

I hope others take preventative action. It's just a pain to have downtime.

lt
 
   / Bent pivot pin #8  
Maybe the pin is the weak link for a reason so that nothing more expensive breaks.
 
   / Bent pivot pin #9  
Heavy pushing into a bank with the 4 n 1 is the only thing that comes to mind that would cause the break. Didn't notice it until I went to grease.
PJ
 
   / Bent pivot pin #10  
Could very well be as in my case it was very cheap to repair.
PJ
 
 
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