SSQA Pin/

[bbxlr8]

Been doing a fair amount of digging & moving soil and tractor was really muddy and caked up over the last month of crazy weather swings here in PA. It was a beautiful day and pulled the L2501 TLB out after work to check over and do full grease/lube.

Got around to the front and lower pin on SSQA was sticking out > 1.5" to the outside.
edit - felt like an idiot after cleaning up & looking at the pics but it was really thick and usually dark when I put away.

Double-checked JIC, but nothing in the manual covers this.
Cleaned up, took pics, pulled bucket and was able to pop back in with the heel of my palm.

Here are my questions:

• Has this happen to you all? (the answer I'm sure is yes given this group)
• Then onto the why - Is this supposed to be a tighter press fit & too loose on this 1 out of 4 or should the weight of the implement normally hold it in place?
• Lastly, did I cause this somehow by misusing in some manner? (don't think so but set me straight)

Learning all the time... Thanks in advance.

 

[NCL4701]

Second pic. The one with the hole and not enough pin. If you look to the left side of the pic I think you’ll see a small hole in the shoulder of the socket that’s oriented perpendicular to the pin. There’s a small bolt that goes through the shoulder of the socket through the pin just to keep it from sliding out.

I haven’t seen thousands of Kubota loaders but the few dozen I’ve seen use those little cross bolts.

I’ve seen other brands that have a groove just inside the inner lip of the socket for a circlip to retain the pin. Regardless, it’s a greasy pin in a greasy hole. There has to be a mechanical means to keep it from sliding out. Look at the remaining pins for the how they’re retained.

Edit: Just thought, you asked if you did something wrong to cause this. No clue. It’s a good idea to take a look at the retainer bolts when you grease the loader to make sure they’re in place and all is well. Could be it came out over time. Could be it caught on something and busted off the head or nut and worked itself out. Not real sure what “abuse” would cause a retainer bolt to come out.

 

[Whatscooking]

Isn't there a bolt to hold it in place?

 

[dirtydeed]

Is there a hole thru the pin and boss on the frame? It appears as though I can see a hole in the boss on the right side of the bore. If so, there is supposed to be a retaining bolt / nylock nut that goes thru keeping the pin in place. I've read that some folks have tightened that bolt/nut too tight which may cause it to break.

Check the other side of your loader frame to see if that bolt is there.


Edit. ha, I see others posted at the same time. ...Put a bolt thru and nylock nut thru it. Leave the nut slightly loose on the bolt. Do not snug it down.

Here's a link to your loader parts:

KubotaPad

kpad.kubota.com

look for PN 180.

 

[bbxlr8]

aha! Makes sense The other side lower was also caked up & bolt head not obvious (was getting dark and maybe I'm a little slow today)

Odds are good that it wasn't tight enough from original assembly. Would be pretty hard but I'm sure, not impossible to break it. Have about 90hrs now but definitely not all loader time. Going to have to drive it back out to clock it right.

Not that critical as just a retainer so I'm sure it is not worth my time talking to the dealer.
Thanks all - easy one

 

[TheOldHokie]

aha! Makes sense The other side lower was also caked up & bolt head not obvious (was getting dark and maybe I'm a little slow today)

Odds are good that it wasn't tight enough from original assembly. Would be pretty hard but I'm sure, not impossible to break it. Have about 90hrs now but definitely not all loader time. Going to have to drive it back out to clock it right.

Not that critical as just a retainer so I'm sure it is not worth my time talking to the dealer.
Thanks all - easy one

I broke the bottom two off in the first few weeks I owned my LA525. They were pretty long and easy to snag. I replaced them with shorter ones and have not had a problem since.

Dan

 

[lynnmor]

Odds are good that it wasn't tight enough from original assembly. Would be pretty hard but I'm sure, not impossible to break it.

The bolt is not to be tightened, in fact there should be a turn or two of play. The nut should be the Nylock type and they should be replaced if there isn't considerable drag on them. My wonderful dealer assembled one place with a plain nut, maybe you had the same thing happen. The reason for leaving them loose is so they don't take a load, with a bit of play between the pin and bushings the bolt would carry the load if tightened.

 

[GreensvilleJay]

curious....
what's the reason to leave the bolt/nut a 'little' loose ?

 

[DustyRusty]

curious....
what's the reason to leave the bolt/nut a 'little' loose ?

The bolt is not to be tightened, in fact there should be a turn or two of play. The nut should be the Nylock type and they should be replaced if there isn't considerable drag on them. My wonderful dealer assembled one place with a plain nut, maybe you had the same thing happen. The reason for leaving them loose is so they don't take a load, with a bit of play between the pin and bushings the bolt would carry the load if tightened.

What Lynnmor said!

 

[GreensvilleJay]

carry what 'load' ?

 

[NCL4701]

carry what 'load' ?

The force that’s applied to the joint by the normal operation of the loader: the load that the pin is there to take. If there was zero play between the socket and pin it wouldn’t matter. In reality there can be some play between the pin and socket and if the bolt is tight so it can’t move back and forth with the pin, it’s very likely some or all of the load intended for the pin will fall to the bolt. Being vastly inadequate for that load, the bolt will fail. So leave it a bit loose. Or don’t and see how often you have to replace retainer bolts.

Personally I’ve never tightened them for the reasons stated above so if you (or someone else) has experience with keeping them tight, it seriously would be interesting to know if they really fail, particularly if it’s on a loader with quite a few hours on it with a little bit of wear at the pins.

 

[TheOldHokie]

The force that’s applied to the joint by the normal operation of the loader: the load that the pin is there to take. If there was zero play between the socket and pin it wouldn’t matter. In reality there can be some play between the pin and socket and if the bolt is tight so it can’t move back and forth with the pin, it’s very likely some or all of the load intended for the pin will fall to the bolt. Being vastly inadequate for that load, the bolt will fail. So leave it a bit loose. Or don’t and see how often you have to replace retainer bolts.

Personally I’ve never tightened them for the reasons stated above so if you (or someone else) has experience with keeping them tight, it seriously would be interesting to know if they really fail, particularly if it’s on a loader with quite a few hours on it with a little bit of wear at the pins.

Coming up on a year and still working fine. The factory bolts sheared off in the first week of use.

I am of the opinion the factory bolt setup is just a low cost alternative to a linchpin. It costs a few pennies less.

They serve two purposes - they retain the pin in the bore and they prevent it from rotating and wearing the bore. They see the same axial and radial shear forces whether tight or loose. All tightening does is add a small amount of tensile load which they can easily handle.

Dan

 

[fried1765]

Coming up on a year and still working fine. The factory bolts sheared off in the first week of use.

I am of the opinion the factory bolt setup is just a low cost alternative to a linchpin. It costs a few pennies less.

They serve two purposes - they retain the pin in the bore and they prevent it from rotating and wearing the bore. They see the same axial and radial shear forces whether tight or loose. All tightening does is add a small amount of tensile load which they can easily handle.

Dan

Tight or loose....is ...."much ado about nothing"!

 

[Russell King]

curious....
what's the reason to leave the bolt/nut a 'little' loose ?

There is no reason to tighten the nut in this situation. The bolt is simply a cross pin to hold the loader pin in place. The nut is to keep the bolt in the hole. It is done with a locking type nut for convenience and cost and some increased reliability.

A double nut arrangement would also work but take longer to install properly.

There is little force that bolt would see so tightening it would not be very detrimental to the arrangement except for when it is banged about. If tight then the stress would always be on the same cross section of the bolt.

Leaving it loose allows the bolt to move to avoid that. It can also eliminate the bolt becoming seized in the hole since it is frequently moved about.

But really not any big deal if nut is snugged up either

 

[bbxlr8]

Wow - thanks again all. No opportunity to get at it today, but will check the other side out tomorrow and report back. Interesting that others encountered this same thing right away.

One thing that has been bothering me is that the inside vacant portion was fully packed with dried gritty mud. I cleaned it several times and sprayed wd40 freely and then drove it back into place just to see if it would.

My gut tells me to fully remove and clean the pin and bore before reseating it properly
w/the retainer bolt / nyloc nut. Any grit would just grind in there (bad) but maybe I am overthinking it as regular greasing should force any contaminants out right...?

 

[NCL4701]

Wow - thanks again all. No opportunity to get at it today, but will check the other side out tomorrow and report back. Interesting that others encountered this same thing right away.

One thing that has been bothering me is that the inside vacant portion was fully packed with dried gritty mud. I cleaned it several times and sprayed wd40 freely and then drove it back into place just to see if it would.

My gut tells me to fully remove and clean the pin and bore before reseating it properly
w/the retainer bolt / nyloc nut. Any grit would just grind in there (bad) but maybe I am overthinking it as regular greasing should force any contaminants out right...?

I would remove it and clean it out if there’s any grit in there. Others may feel differently. I don’t like grit in joints, even if they’re just pins and bosses.

 

[GreensvilleJay]

What's interesting is that on my BX23S, probably half of all the pins ARE firmly bolted. They have welded 'wings' on the pins, which are then bolted to the boom or frame. The bucket and BH legs are the two I remember. Be nice to talk to the 'engineers' on how it was decided this pin is fixed, that one isn't.

 

[TheOldHokie]

Wow - thanks again all. No opportunity to get at it today, but will check the other side out tomorrow and report back. Interesting that others encountered this same thing right away.

My gut tells me to fully remove and clean

In the case of my LA525 the factory bolts were a good 1/2" longer than needed. My assumption is they were exposed to ground contact and sheared off from getting caught against rocks in multiple loads of rubble fill I was moving with the loader. Excessive length not tight or loose was the problem.

I replaced them with shorter ones and regular hex nuts which I had on hand. I tightened the nuts to prevent them from backing off. Nylock nuts could have been left loose. No more sheared bolts since the shorter ones were installed.

Kubota has used multiple designs for retaining their loader pins but they all have one thing in common - they prevent the loader pin from rotating. They clearly want to eliminate sliding wear on the parent bores in the loader arms.

My opinion aligns with Mssr. Fried - tight or loose is much ado about nothing.

Dan

 

[DustyRusty]

If there was grit in the bore, then there possibly was insufficient grease to lubricate the pin. The bolt then acted as a shear pin when movement tried to move the pin because of lack of lubrication. Hence it broke! Do you lubricate all your pins and bushings every 10 hours as the manual says to do? Do you use the correct type of grease as is recommended in the manual? Have you even read the manual? If not, then you might be guilty of tractor abuse, and if it is reported to the Society for the prevention of tractor cruelty, you can be subject to huge fines and possibly a lengthy prison term. Tractor abuse is a serious crime that has been on the rise for the past 3 decades. Help stamp out tractor abuse by reporting violators to the TBS (Tractor Abuse Administration). Please keep in mind that it is your tax dollars that go to supporting the TBA to the tune of 7 1/2 Billion Dollars per year.

 

[TheOldHokie]

If there was grit in the bore, then there possibly was insufficient grease to lubricate the pin. The bolt then acted as a shear pin when movement tried to move the pin because of lack of lubrication. Hence it broke! Do you lubricate all your pins and bushings every 10 hours as the manual says to do? Do you use the correct type of grease as is recommended in the manual? Have you even read the manual? If not, then you might be guilty of tractor abuse, and if it is reported to the Society for the prevention of tractor cruelty, you can be subject to huge fines and possibly a lengthy prison term. Tractor abuse is a serious crime that has been on the rise for the past 3 decades. Help stamp out tractor abuse by reporting violators to the TBS (Tractor Abuse Administration). Please keep in mind that it is your tax dollars that go to supporting the TBA to the tune of 7 1/2 Billion Dollars per year.

A much simpler explanation - grit entered the bore AFTER the overly long bolts got caught and sheared allowing the lubed pins to back out and dirt to fill the bores.

But hey - more fun to make it complicated and blame the operator.


Dan