Pin Hole Too Big

downsizingnow48 · Apr 19, 2016

Messick's has a new swing frame for the BT820 listed for $762 dollars. If it was my machine, that is what I would do. I should have looked that up in the first place. Could have had it installed and good as new by now.

Coyote machine · Apr 19, 2016

downsizingnow48 said:
Messick's has a new swing frame for the BT820 listed for $762 dollars. If it was my machine, that is what I would do. I should have looked that up in the first place. Could have had it installed and good as new by now.

No there's an idea that solves the problem once and for all, no cob job required. Inexpensive, no, fixed, yes.

tjkubota93 · Apr 22, 2016

If you buy equipment anywhere, especially an auction, you are lucky if that wore out pin boss and rigged up wiring is all you find.

Alot of rental companies run stuff till their unskilled mechanics can't patch it anymore, then auction it off.

I have almost give up on renting stuff because of how crappy it is when you pick it up.

Some companies are way better-they usually rent cranes and bucket trucks.

The majority of equipment (and work vehicles) I have seen are treated with very little care. Run it till it stops, then patch together as quick as possible to continue making money.

CalG · Apr 22, 2016

downsizingnow48 said:
Messick's has a new swing frame for the BT820 listed for $762 dollars. If it was my machine, that is what I would do. I should have looked that up in the first place. Could have had it installed and good as new by now.

I can't even imagine spending $762 + shipping to do such a repair.
cut the old worn piece off, weld on a new one, Done!

but hey, It's your money.

aczlan · Apr 22, 2016

CalG said:
I can't even imagine spending $762 + shipping to do such a repair.
cut the old worn piece off, weld on a new one, Done!
but hey, It's your money.

I would first pull the pins on both sides so I could compare them (and the holes)to see if its actually worn, or if its just an undersized pin...

Aaron Z

downsizingnow48 · Apr 22, 2016

Yes that is the necessary start to anything. Folks have offered lots of ideas from "cob" to Cadillac. Need to hear from OP and pix of the pins and holes.

Mike in Dewey · Apr 27, 2016

Attached are pictures of the washer freshly ground off along with a side-by-side of a new pin versus the one removed. Best guess is that the assembly has not seen a bit of grease since it was manufactured. Strangely, the other side is greased and is good as new.

I am one dang bolt away from removing the swingframe from the boom. Heat and cussing failed to convince it to yield so the just delivered slide hammer is about to be put to the test. This was after constructing a Rube Goldberg frame to prevent the boom/dipperstick/bucket assembly from falling over and creating a cart that would hold the mainframe and stabilizers so that they could be wheeled out of the way when disconnected. It is an interesting education. Turns out that I have a welder/machinist a couple of hills from here and once that final bolt is coerced out I will be delivering the swingframe and DOM tubing to him. Hopefully, the end is near.

GPintheMitten · Apr 27, 2016

The pictures tell the story. Glad you're making headway.

LD1 · Apr 27, 2016

Was the washer ONLY welded to the pin? If so, I still maintain it is purley cosmetic.

If the washer were welded to the swing frame, or both, then I could see it as a temp solution to lessen slop.

But from the looks of it and where it wore, there looks to be little wear around the center of the pin where the cylinder hooks. And this is the only place that should need it. The pin is bolted in place and shouldnt rotate in the swing frame. So there shouldnt be much wear there? Other than the pounding it takes. Certainly an odd occurance

Mike in Dewey · Apr 28, 2016

The washer was welded only to the pin. Had I been smart enough to put a mirror to the bottom of the pin, I would have noticed that the bottom bracket was hanging by a thread to the pin and a tap with a chisel would have negated the need to grind. There was minimal wear on the pin where it mates with the cylinder hook, but while I have it all apart I intend to replace that bushing also. Does anyone know if that should simply knock out or do I need a hydraulic press to remove and replace?

LD1 · Apr 28, 2016

Sometimes they hammer out easily. Other times even a 20t press wont get it, you just have to try and see.

A die grinder der and smapp carbide bur to split the bushing makes them come out easy if all else fails

downsizingnow48 · Apr 28, 2016

Thx for the new pix. This is a real puzzle. How one side would be ok and the other side such a mess. And as LD1 says, what happened to make the pin start chewing up the swing frame, while the part of the pin in the cylinder rod end stayed more or less ok.

GPintheMitten · Apr 28, 2016

downsizingnow48 said:
Thx for the new pix. This is a real puzzle. How one side would be ok and the other side such a mess. And as LD1 says, what happened to make the pin start chewing up the swing frame, while the part of the pin in the cylinder rod end stayed more or less ok.

I would say that the cylinder end was hard fasted to the pin. No rotation put all the force above andbelow that area, which had no grease so it wore out the hole in the swing arm which is softer than the pin.

aczlan · Apr 28, 2016

GPintheMitten said:
I would say that the cylinder end was hard fasted to the pin. No rotation put all the force above andbelow that area, which had no grease so it wore out the hole in the swing arm which is softer than the pin.

Yep. My guess would be that the grease zerk on the cylinder stopped taking grease and whoever did the service didn't notice, or didn't care until the pin fell out. Then they probbaly welded it back together a couple of times and eventually put the washer on top.

Aaron Z

LD1 · Apr 28, 2016

The way the pin is retained, it HAS to rotate withing the cylinder clevis. It CANNOT rotate within the swing post unless the bracket breaks.

Which is quite possibly what happened. THEN it would be allowed to spin in the swing post. Which wasn't bushed with hard material, because as designed...it isn't needed

5030 · Apr 28, 2016

aczlan said:
Was the paint fresh, or had they been running it like that for a while?
IMO, fresh paint on something at an auction is a red flag. If they had been running with the washer for a while, they probably put it on to get it back in service while they were getting a replacement in (or waiting till the next budget year to order a new one).

True, but if they have been using it like that for a time, they may not have considered it to be more than "normal wear and tear" for such a machine.

Aaron Z

Around here, we call that the Five Gallon Finish...lol

I've seen some 'pretty' units where the 'finisher' just painted over old grease and called it good. Some things (especially at auctions) amaze me. Some buyers amaze me as well.

tjkubota93 · Apr 28, 2016

LD1 said:
The way the pin is retained, it HAS to rotate withing the cylinder clevis. It CANNOT rotate within the swing post unless the bracket breaks.

Which is quite possibly what happened. THEN it would be allowed to spin in the swing post. Which wasn't bushed with hard material, because as designed...it isn't needed

It was broke in the picture

tjkubota93 · Apr 28, 2016

LD1 · Apr 29, 2016

tjkubota93 said:
It was broke in the picture

Yep. But could have have broke during removal.

In either case, once fixed and kept freely spinning with lube in the cylinder eye, the swing frame shouldn't wear at all