Tractor backhoe - homemade

[Kyle_in_Tex]

I was thinking it is much easier to replace a pin than a bushing too???

 

[4570Man]

I was thinking it is much easier to replace a pin than a bushing too???

It is.

 

[4570Man]

I don’t foresee it being a problem either way. Commercial backhoes go thousands of hours before changing them.

 

[hseII]

I was thinking it is much easier to replace a pin than a bushing too???

As long as you can get the pin out without compromising the bushing &/or base metal/housing.

Hard Pins for me.

 

[rScotty]

I was thinking it is much easier to replace a pin than a bushing too???

Yes, and that's probably the first thing that jumped out of me. Not only easier physically, but less expensive. The average guy with a garage can handle repairs to a fairly large hoe. Or if he had rather, there are literally thousands of small welding/repair shops that can. Pin wear becomes more field-repairable & without the whole problem of weld cracking and heat treat.

Then it occurred to me that this is (another) whole field of mechanics that I know almost nothing about. I simply haven't sat down and worked through the arguments for hard vs soft pins and bushings in high pressure, low speed applications with grease.
Just to check that I'm not hallucinating, I just went out to my JD310SG and touched a file to a couple of the main BH pins in the bucket and booms. They are soft, although of large diameter - the smallest is around 2.25" across. That's about what I would expect. Lateral movement is constrained by a thin hard washer and big cotter through a hole in the pin.
rScotty

 

[Kyle_in_Tex]

I want to hear about an easy way to replace bushings?

 

[4570Man]

I want to hear about an easy way to replace bushings?

They sure aren’t easy to do on my backhoe. I’ve never actually changed one and they’re in perfect condition after 2400 hours, but I contemplated doing it when I couldn’t get grease in 2.

 

[dfkrug]

I want to hear about an easy way to replace bushings?

The times I have done it on my Bulgarian backhoe attachment, it has not been easy. These plain bearings were only 25mm and 30mm, which I can now get from China fairly cheap. Teflon coated. The toughest one I did was in 5 segments, and I welded some scraps of steel on the inside so my drift pin could get a purchase to drive them out.

 

[dfkrug]

I just went out to my JD310SG and touched a file to a couple of the main BH pins in the bucket and booms. They are soft...

I found my Kubota pins to be fairly hard, and my Deere pins, soft.

 

[rScotty]

I found my Kubota pins to be fairly hard, and my Deere pins, soft.

Same on mine. Neither Kubota nor Deere has too much overall wear, although the Deere with 6000 fairly hard hours but decent service schedule is beginning to show too much slop at the QC bucket. The swing, table, and booms are all still tight - including the extendahoe.
My experience is that it isn't uncommon for Deere 310s to benefit from new pivot pins in some locations after 7 to 10K hrs. Pin replacement is well within the capability of the home mechanic. Given a saw and a drill press you can even make your own from round stock if necessary.
So far I'm kinda liking the softer steel pin & hardened bushing approach.

But now my curiosity is up and I'm wondering just what argument drove European & Japanese designers to favor different steels in the same application?
rScotty