B4672A Top link pins

[Mountainman]

Good morning everyone. Picked up a b7510 last night with a b4672a backhoe. Old man passed away and the nephew who inherited it didn't know where the top link pins were. Part number is 70050-94378. They are apparently a special hardened pin but are obsolete. Anyone found a substitute for them? Thank you

 

[nbryan]

Look at 70050-00856 it might be a new p/n for the clevis pins you're looking for.

 

[Mountainman]

Look at 70050-00856 it might be a new p/n for the clevis pins you're looking for.

On messicks is says that pin is for the Grand L series. Not sure what the difference would be

 

[mikester]

try your local farm supply for 3ph pins

 

[nbryan]

On messicks is says that pin is for the Grand L series. Not sure what the difference would be

Says on that page it fits the b4672a.

 

[Henro]

try your local farm supply for 3ph pins

Those pins are claimed to be stronger than standard 3PH pins. When I lost one I used a grade 8 Bolt to make a replacement from. It was a longer bolt, that had enough area along its length with no threads that I could cut the threads off and still have the pin part.

Being a three-point hitch backhoe, it would be wise for the OP to check and make sure the tractor has a heavy duty top link bracket installed. I imagine it does, as it sounds likely that the original purchaser probably bought it from a dealer as a unit. But you never know

A second piece of unsolicited advice would be for the OP to read the manual on the backhoe and make sure that the safety bar that goes across the bottom under the three-point arms is still there and functional. This is important to ensure that if a pin would break the backhoe does not raise up and squeeze the operator between the seat and the ROPS. I recall reading years ago of a fatality that occurred when this happened to someone using a three-point hitch backhoe on a tractor. Don’t remember any details other than what happened.

Edited a couple typos…

 

[Mountainman]

Says on that page it fits the b4672a.

Yes but b4672a backhoe fits many tractors. Different pins for different configurations

 

[Mountainman]

Those pins are claimed to be stronger than standard 3PH pins. When I lost one I used a grade 8 Bolt to make a replacement from. It was a longer bolt, that had enough area along its length with no threads that I could cut the threads off and still have the pin part.

Being a three-point hitch backhoe, it would be wise for the OP to check and make sure the tractor has a heavy duty top link bracket installed. I imagine it does, as it sounds likely that the original purchaser probably bought it from a dealer as a unit. But you never know

A second piece of unsolicited advice would be for the OP to read the manual on the backhoe and make sure that the safety bar that goes across the bottom under the three-point arms is still there and functional. This is important to ensure that if a pin would break the backhoe does not raise up and squeeze the operator between the seat and the ROPS. I recall reading years ago of a fatality that occurred when this happened to someone using a three-point hitch backhoe on a tractor. Don’t remember any details other than what happened.

Edited a couple typos…

Yes it has heavy duty top link bracket as well as the safety bar. Called messicks and they state all kubota oem top link pins are hardened grade 12 pins so they would work fine.

 

[Henro]

I think I would take that grade 12 claim with a grain of salt.

SAE grade 9 looks to be approximately 180,000 psi tensile strength.

Metric grade 12.9 seems to be in the range of approximately 175,000 psi tensile strength.

Perhaps whoever you spoke with was referring to a metric grade 12.9? Certainly better than my grade 8 bolt which is rated at 150 thousand PSI tensile strength..

Just going by what I found on the Internet. No expert here. But we all know whatever you read on the Internet must be true!

I do feel the same though, as long as I could verify the pin grade. Grade 2, no way. Grade 8 should be OK... Higher grade all the better.

 

[Mountainman]

I think I would take that grade 12 claim with a grain of salt.

SAE grade 9 looks to be approximately 180,000 psi tensile strength.

Metric grade 12.9 seems to be in the range of approximately 175,000 psi tensile strength.

Perhaps whoever you spoke with was referring to a metric grade 12.9? Certainly better than my grade 8 bolt which is rated at 150 thousand PSI tensile strength..

Just going by what I found on the Internet. No expert here. But we all know whatever you read on the Internet must be true!

I do feel the same though, as long as I could verify the pin grade. Grade 2, no way. Grade 8 should be OK... Higher grade all the better.

I agree. Not sure they really know but I'd guess oem kubota are better than aftermarket at least

 

[mikester]

Those pins are claimed to be stronger than standard 3PH pins. When I lost one I used a grade 8 Bolt to make a replacement from. It was a longer bolt, that had enough area along its length with no threads that I could cut the threads off and still have the pin part.

Being a three-point hitch backhoe, it would be wise for the OP to check and make sure the tractor has a heavy duty top link bracket installed. I imagine it does, as it sounds likely that the original purchaser probably bought it from a dealer as a unit. But you never know

A second piece of unsolicited advice would be for the OP to read the manual on the backhoe and make sure that the safety bar that goes across the bottom under the three-point arms is still there and functional. This is important to ensure that if a pin would break the backhoe does not raise up and squeeze the operator between the seat and the ROPS. I recall reading years ago of a fatality that occurred when this happened to someone using a three-point hitch backhoe on a tractor. Don’t remember any details other than what happened.

Edited a couple typos…

OP said TOP LINK PINS

If you mount a BH using your top link you still have a weak BH mounted to a weak 3PH