Broken casting on BH 77 excavator

[JPM]

I just bought a new 3302 tractor with a BH77 excavator attached from dealer. I have only 8 hours on tractor, and have barely used the excavator. Yesterday this casting broke - its at the area where the safety pin is installed to keep excavator from swinging from right to left. Has this happened to anyone else? I have not abused the tractor in any way, in fact I am a new tractor owner and have been babying the heck out of it. Seems like a bad casting but wanted to see what anyone else thought? Thanks

 

[TheOldHokie]

I just bought a new 3302 tractor with a BH77 excavator attached from dealer. I have only 8 hours on tractor, and have barely used the excavator. Yesterday this casting broke - its at the area where the safety pin is installed to keep excavator from swinging from right to left. Has this happened to anyone else? I have not abused the tractor in any way, in fact I am a new tractor owner and have been babying the heck out of it. Seems like a bad casting but wanted to see what anyone else thought? Thanks

Let me be the first to chastize you for calling your backhoe an excavator

I would call that a defect in materials and it should be covered by warranty.

Dan

 

[Tarmy]

What he said…on both points!^^^^^

 

[dirtydeed]

What he said…on both points!^^^^^

I just bought a new 3302 tractor with a BH77 excavator attached from dealer. I have only 8 hours on tractor, and have barely used the excavator. Yesterday this casting broke - its at the area where the safety pin is installed to keep excavator from swinging from right to left. Has this happened to anyone else? I have not abused the tractor in any way, in fact I am a new tractor owner and have been babying the heck out of it. Seems like a bad casting but wanted to see what anyone else thought? Thanks

That sucks. But you're not the first. I've seen this before.

Did you start to swing with the lock in place??? Or possibly hit something with the hoe when turning?

I believe that may be what you hear from your dealer...I hope not.

 

[JPM]

That sucks. But you're not the first. I've seen this before.

Did you start to swing with the lock in place??? Or possibly hit something with the hoe when turning?

I believe that may be what you hear from your dealer...I hope not.

No I didnt hit anything with it. Pin was in when it broke. I noticed a fair amount of wear on the pin and a fair amount of wear in the hole that the pin fit through. You have heard of this before? Wonder if its undersized or a defect in casting?

 

[dirtydeed]

No I didnt hit anything with it. Pin was in when it broke. I noticed a fair amount of wear on the pin and a fair amount of wear in the hole that the pin fit through. You have heard of this before? Wonder if its undersized or a defect in casting?

I think its a pretty weak point in the casting. Someone else on this forum had this happen fairly recently as well. I don't recall if they ever admitted to any wrong doing...but I think the dealer replaced it.

I don't use the swing lock at all...for this very reason. It's just too easy to forget that the pin is in there and the operator tries to swing the boom.

Question is, do you have KTAC insurance on the machine? If so, you should be fine.

 

[fried1765]

I think its a pretty weak point in the casting. Someone else on this forum had this happen fairly recently as well. I don't recall if they ever admitted to any wrong doing...but I think the dealer replaced it.

I don't use the swing lock at all...for this very reason. It's just too easy to forget that the pin is in there and the operator tries to swing the boom.

Question is, do you have KTAC insurance on the machine? If so, you should be fine.

"I don't use the swing lock at all"
BINGO !

 

[fried1765]

No I didnt hit anything with it. Pin was in when it broke. I noticed a fair amount of wear on the pin and a fair amount of wear in the hole that the pin fit through. You have heard of this before? Wonder if its undersized or a defect in casting?

"a fair amount of wear on the pin and a fair amount of wear in the hole"

This, on a machine with only 8 hours on the clock?
This is a transport lock,.... not a moving part!
How can it be ?

 

[JPM]

"a fair amount of wear on the pin and a fair amount of wear in the hole"

This, on a machine with only 8 hours on the clock?
This is a transport lock,.... not a moving part!
How can it be ?

The pin fits in the casting hole loosely. I used the tractor for moving wood chip over some pretty bumpy ground for most of the 8 hours. The wear on the pin lines up with the lower edge of the casting hole and the casting shows wear in one location where the pin rests. I am thinking that the pin and casting wear is due to vibration and differential movement between pin and casting?

 

[JPM]

"a fair amount of wear on the pin and a fair amount of wear in the hole"

This, on a machine with only 8 hours on the clock?
This is a transport lock,.... not a moving part!
How can it be ?

Here are some photos of the wear

"a fair amount of wear on the pin and a fair amount of wear in the hole"

This, on a machine with only 8 hours on the clock?
This is a transport lock,.... not a moving part!
How can it be ?

Here are some photos of the wear

 

[fried1765]

Here are some photos of the wear

Here are some photos of the wear

I still do not understand "wear" on a pin that is not a pivot point.

 

[Chanceywd]

I think its a pretty weak point in the casting. Someone else on this forum had this happen fairly recently as well. I don't recall if they ever admitted to any wrong doing...but I think the dealer replaced it.

I don't use the swing lock at all...for this very reason. It's just too easy to forget that the pin is in there and the operator tries to swing the boom.

Question is, do you have KTAC insurance on the machine? If so, you should be fine.

Mine has never been back in since delivery. I have a lot of slopes here and like to be able to reach back and turn it to the uphill side for ballast when I travel across them. Also when putting it in the garage I can swing it to get in further. I keep it in the holder so if needed for like blown hose on the swing should happen I could lock it then.

Bill

 

[William1]

Not a 'wear point'. At most, vibration over time 'might' cause the paint to 'wear off'. It is not a tight fit for the pin, in fact deliberately sloppy to make alignment (pin inserting) easy, the point is to keep the hoe from swinging on its' own. I only use the (other) one to prevent the hoe from drooping when parked.
I'll wager the dealer will tell you it was an owner error. I do not see anything on the casting that leads me to think it had a defect.
On the plus side, it is not critical unless trailering and even then, you can chain it to prevent movement.

 

[fried1765]

Not a 'wear point'. At most, vibration over time 'might' cause the paint to 'wear off'. It is not a tight fit for the pin, in fact deliberately sloppy to make alignment (pin inserting) easy, the point is to keep the hoe from swinging on its' own. I only use the (other) one to prevent the hoe from drooping when parked.
I'll wager the dealer will tell you it was an owner error. I do not see anything on the casting that leads me to think it had a defect.
On the plus side, it is not critical unless trailering and even then, you can chain it to prevent movement.

100% AGREED!
(I have NEVER used either of my two pins!)

 

[hagrid]

Here are some photos of the wear

Here are some photos of the wear

Looks like a ductile fracture to me and I don't see any inclusions or other usual casting flaws. It's tough for me to determine if the failure was cyclical.

 

[dirtydeed]

OP - just for giggles. pull the boom up and lock it (not the swing lock). Move the dipper by hand side to side (engine off) and see if there is any excessive side to side slop in the main boom knuckle or in the swing cylinder joints.

 

[mikester]

Next time remember to pull the pin before operating the swing

 

[hodge]

Welcome to the forum!
You were doing loader work over rough ground, by your description, for about 8 hours. With the pin in place, there would be a significant amount of leverage on that pin and the casting. From the looks of it, it's not a casting defect, but a failure due to overload. As suggested, the pin should not have been left in place. Whether Kubota will cover it, you'll have to ask.
I'm curious- in the owners manual, what is the instruction for using the pin?

 

[TheOldHokie]

Let me be the first to chastize you for calling your backhoe an excavator

I would call that a defect in materials and it should be covered by warranty.

Dan

Welcome to the forum!
You were doing loader work over rough ground, by your description, for about 8 hours. With the pin in place, there would be a significant amount of leverage on that pin and the casting. From the looks of it, it's not a casting defect, but a failure due to overload. As suggested, the pin should not have been left in place. Whether Kubota will cover it, you'll have to ask.
I'm curious- in the owners manual, what is the instruction for using the pin?

I am curious as well. Why would locking the hoe when its not in use be a problem?

Dan

 

[GreensvilleJay]

2nd picture in post #10 shows a LOT of RUST on the inside of the hole. As it's an 8 hour old machine, WHERE did all that rust come from ?
Real curious about that !
Also the powder coat is all chipped in there as well.
FYI... I leave both pins in my BX23S,fairly snug fit. Always have to move BH to the left to release the pin.

I find it hard to believe you could break it ,though I'd like to hear others who have OP's BH respond.