More stuck pins.

I'm trying to get the bucket off the dipper stick but the pins won't budge.
Here's a sad looking picture... kinda like a crab that lost a claw.

Here is a closeup of the 4 pins I need to remove. I've hit them as hard as I can with a 3 lb. hammer and a 3/4" pin driver but there is no movement at all. There has got to be a way to get these pins to move.

I am thinking about a famous quote from "Citizen Kane": ROSEBUD - warm it up a bit

SkidRoe said:

I am thinking about a famous quote from "Citizen Kane": ROSEBUD - warm it up a bit

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I had 4 in 1 bucket pins like that. I used a porta power pull ram. Welded an adaptor to the end of the pin, slid a collar between the ram and the boss and pumped the ram up. Even with full force on it i had to use a drift and hammer to get them to start moving. One even needed heat (as SR mentioned). Some times they can be in there so tight that you may even need to cut the pins and knock them out one piece at a time.
Do you have access to a workshop press? I know something that size is going to be HEAVY and doing it will not be fun, but its an option.

Tazza said:

I had 4 in 1 bucket pins like that. I used a porta power pull ram. Welded an adaptor to the end of the pin, slid a collar between the ram and the boss and pumped the ram up. Even with full force on it i had to use a drift and hammer to get them to start moving. One even needed heat (as SR mentioned). Some times they can be in there so tight that you may even need to cut the pins and knock them out one piece at a time.
Do you have access to a workshop press? I know something that size is going to be HEAVY and doing it will not be fun, but its an option.

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Great idea about welding the adapter to the pin... I may try that after I try SR's heat method.
bTw... I got bored waiting for my hose order to arrive so I started stripping the paint from the boom. It's amazingly light for it's size... I was able to lift it by hand (alone) and put it on the sawhorses.

Jyuma said:

Great idea about welding the adapter to the pin... I may try that after I try SR's heat method.
bTw... I got bored waiting for my hose order to arrive so I started stripping the paint from the boom. It's amazingly light for it's size... I was able to lift it by hand (alone) and put it on the sawhorses.

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You should come to Australia, i have a hoe that needs attention, you will be the local master of the hoe, you are more than welcome to work on mine for me
Its going to look like new!

Tazza said:

You should come to Australia, i have a hoe that needs attention, you will be the local master of the hoe, you are more than welcome to work on mine for me
Its going to look like new!

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The master of the hoe... a dubious distinction indeed.

Jyuma said:

The master of the hoe... a dubious distinction indeed.

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hehe, so very true.

Tazza said:

hehe, so very true.

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Well... two weeks of pounding and I finally got half the pins out. I used a puller with heat and a whole lot of cussing.
Here's a picture of the puller attached. Notice the large washer laying on the ground just to the left of the block of wood under the bucket. I had to cut the washer off so the paws of the puller could get behind the bushing.

The next picture shows to paws of the puller in more detail.

Jyuma said:

Well... two weeks of pounding and I finally got half the pins out. I used a puller with heat and a whole lot of cussing.
Here's a picture of the puller attached. Notice the large washer laying on the ground just to the left of the block of wood under the bucket. I had to cut the washer off so the paws of the puller could get behind the bushing.

The next picture shows to paws of the puller in more detail.

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Looks like I'll need to cut the other two pins out. I pounded until the puller broke and all I got for it was the bushing in the tip of the dipper stick moved about 1/4" before hitting the far side bushing in the bucket and then stopping cold.
The pin is frozen solid inside the bushing that traverses through the end of the dipper. I can't get the pin to move and the bushing it is frozen to is captive between the bucket bushings.
I'm guessing that once I cut the pin (both ends between the dipper and the bucket) I'll be able to knock the bushing all the way out... with the pin frozen inside... and then use a wedge to open the bushing slightly (at the split) and remove what remains of the pin.
It looks like the pin remnants remaining in the bucket bushing will move fairly easily so I should have no trouble pounding them out.
What diameter bar stock should I buy to make new pins? I put a vernier on the pins and they measure between 1.100 and 1.115. My question is... 1 1/8" bar stock is 1.125 which will not make it through the bushings very well. Does 1 1/8" bar stock actually measure less that 1.125 and can I expect the bar stock to be .010 to .020 undersized?

Jyuma said:

Looks like I'll need to cut the other two pins out. I pounded until the puller broke and all I got for it was the bushing in the tip of the dipper stick moved about 1/4" before hitting the far side bushing in the bucket and then stopping cold.
The pin is frozen solid inside the bushing that traverses through the end of the dipper. I can't get the pin to move and the bushing it is frozen to is captive between the bucket bushings.
I'm guessing that once I cut the pin (both ends between the dipper and the bucket) I'll be able to knock the bushing all the way out... with the pin frozen inside... and then use a wedge to open the bushing slightly (at the split) and remove what remains of the pin.
It looks like the pin remnants remaining in the bucket bushing will move fairly easily so I should have no trouble pounding them out.
What diameter bar stock should I buy to make new pins? I put a vernier on the pins and they measure between 1.100 and 1.115. My question is... 1 1/8" bar stock is 1.125 which will not make it through the bushings very well. Does 1 1/8" bar stock actually measure less that 1.125 and can I expect the bar stock to be .010 to .020 undersized?

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This is where it becomes interesting.
I went through this a few years ago with my steel supplier when i wanted some 1 1/4" 4140 steel. I said i wanted 1 1/4" for pins, he said you want H3 or H2 spec as it is ground undersize The H numbers indicate the tollerance that it is ground to. If you talk to you supplier and say you want 1 1/8" and whatever the spec is that makes it .010 undersize you should be good to go. Just make sure the fit isn't too tight if its to run through a bushing, you need a film of grease in there still.

Tazza said:

This is where it becomes interesting.
I went through this a few years ago with my steel supplier when i wanted some 1 1/4" 4140 steel. I said i wanted 1 1/4" for pins, he said you want H3 or H2 spec as it is ground undersize The H numbers indicate the tollerance that it is ground to. If you talk to you supplier and say you want 1 1/8" and whatever the spec is that makes it .010 undersize you should be good to go. Just make sure the fit isn't too tight if its to run through a bushing, you need a film of grease in there still.

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Tazza
You mentioned 4140 steel for the pins. 4140 is intended to be worked in it's annealed state but then hardened by heat and quenching once in it's finished form. However, I was able to cut through my 1.125 pins with a standard metal cutting saws-all blade in under 1 minute. I doubt that I could have done that if the pins were hardened... in fact, I am certain I could not. Therefore I must assume that the pins used in my Thomas backhoe are not 4140 but plain old mild steel.
Wouldn't it be preferable to use mild steel and replace the pins as they wear rather than hardened steel which would wear the sleeves and bushings rather than the pins?

Jyuma said:

Tazza
You mentioned 4140 steel for the pins. 4140 is intended to be worked in it's annealed state but then hardened by heat and quenching once in it's finished form. However, I was able to cut through my 1.125 pins with a standard metal cutting saws-all blade in under 1 minute. I doubt that I could have done that if the pins were hardened... in fact, I am certain I could not. Therefore I must assume that the pins used in my Thomas backhoe are not 4140 but plain old mild steel.
Wouldn't it be preferable to use mild steel and replace the pins as they wear rather than hardened steel which would wear the sleeves and bushings rather than the pins?

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4140 before hardening is pretty good at wear resistance, not as good when nitrided though. Easily cut with a standard saw blade in that state too.
With regard to the bushings, i thought the same. But Bobcat have never done this in the lift arms or any other pivot point. If the bushings are repalceable its fine to use hardened pins. For the amount of work you will be putting your hoe through, i'd doubt it would wear out. The two surfaces should be smooth and a layer of grease between. Ideally they should never wear like that, even if one is harder than the other, we know its not a perfect world, so naturally its never like that is ist?
With that said, i don't see why mild wouldn't work, but can you get precision ground mild steel? or do they only cater for the 'good' stuff? Most of the round mild i have seen is just rolled, you still need to machine it to size.

Tazza said:

4140 before hardening is pretty good at wear resistance, not as good when nitrided though. Easily cut with a standard saw blade in that state too.
With regard to the bushings, i thought the same. But Bobcat have never done this in the lift arms or any other pivot point. If the bushings are repalceable its fine to use hardened pins. For the amount of work you will be putting your hoe through, i'd doubt it would wear out. The two surfaces should be smooth and a layer of grease between. Ideally they should never wear like that, even if one is harder than the other, we know its not a perfect world, so naturally its never like that is ist?
With that said, i don't see why mild wouldn't work, but can you get precision ground mild steel? or do they only cater for the 'good' stuff? Most of the round mild i have seen is just rolled, you still need to machine it to size.

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Hmmm... It seems every time you answer one of my questions you give me 3 more things to think about.
Below is a picture of the pivot point pin, bushings and washers used to connect the end of dipper stick to the bucket. The first thing you need to know is that there is not a single grease Zerk anywhere to be found and there is no way to even get any grease into what should be a critical pivot point. I suppose this is the reason the pin was frozen solid inside the sleeve to begin with.
Take a look at the picture... viewing from left to right we see the left end of the pin has a large washer welded to it. When the pin is inserted through the bushing in the bucket and then through the end of the dipper and then finally through the opposite side bushing on the bucket, this welded washer will come to rest against the left side of the bucket bracket and become captive. (note: the bucket is not shown).
Moving to the right along the pin we come to another washer. This washer is used as a spacer between the bucket bushing and the end of the dipper stick. Next we see a bushing. This bushing is a split bushing presumably so it can be pressed into the end of the dipper stick. Next we see a sleeve... this sleeve has the same ID as the bushing but the OD is much smaller. I assume the function of this sleeve is to take up the space between the two split bushings that are pressed into the end of the dipper stick.
Next there is a second bushing followed by another washer that acts like a spacer between the dipper stick and the other side bucket bushing and then finally a bolt goes through the outside of the bucket bushing and through the pin securing the entire pin assembly in place.
I say again... there is no provision of any kind for greasing this pivot point. What would be the point in using precision pins and mating surfaces when the pivot cannot be greased? How can that be? I can understand no grease on the bucket bushings... the pin is bolted to the bucket bushing and cannot rotate inside so there is no need for grease at that point but surely at least the locations where the pin goes through the two bushings inside the tip of the dipper stick should be greased... but there is no way to grease those points short of removing the pins and forcing grease in..



Below is a photo of the end of the dipper stick where the bucket attaches... no grease Zerk's here either. Note: the end looks the same no matter which direction I snap the photo. There just isn't any way to grease this critical (I would think) pivot point.

Jyuma said:

Hmmm... It seems every time you answer one of my questions you give me 3 more things to think about.
Below is a picture of the pivot point pin, bushings and washers used to connect the end of dipper stick to the bucket. The first thing you need to know is that there is not a single grease Zerk anywhere to be found and there is no way to even get any grease into what should be a critical pivot point. I suppose this is the reason the pin was frozen solid inside the sleeve to begin with.
Take a look at the picture... viewing from left to right we see the left end of the pin has a large washer welded to it. When the pin is inserted through the bushing in the bucket and then through the end of the dipper and then finally through the opposite side bushing on the bucket, this welded washer will come to rest against the left side of the bucket bracket and become captive. (note: the bucket is not shown).
Moving to the right along the pin we come to another washer. This washer is used as a spacer between the bucket bushing and the end of the dipper stick. Next we see a bushing. This bushing is a split bushing presumably so it can be pressed into the end of the dipper stick. Next we see a sleeve... this sleeve has the same ID as the bushing but the OD is much smaller. I assume the function of this sleeve is to take up the space between the two split bushings that are pressed into the end of the dipper stick.
Next there is a second bushing followed by another washer that acts like a spacer between the dipper stick and the other side bucket bushing and then finally a bolt goes through the outside of the bucket bushing and through the pin securing the entire pin assembly in place.
I say again... there is no provision of any kind for greasing this pivot point. What would be the point in using precision pins and mating surfaces when the pivot cannot be greased? How can that be? I can understand no grease on the bucket bushings... the pin is bolted to the bucket bushing and cannot rotate inside so there is no need for grease at that point but surely at least the locations where the pin goes through the two bushings inside the tip of the dipper stick should be greased... but there is no way to grease those points short of removing the pins and forcing grease in..



Below is a photo of the end of the dipper stick where the bucket attaches... no grease Zerk's here either. Note: the end looks the same no matter which direction I snap the photo. There just isn't any way to grease this critical (I would think) pivot point.

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It is a silly design isn't it? At least the attachments i have seen without grease nipples ran nylon bushings.
You can make it greased if you want to. If you have access to a lathe, chuck it up and drill a hole from the end with the washer, drill it so its just over half way though. Drill one or two small cross holes half way down at 90 degrees to the one you did before. This will allow grease to run from the end of the pin down and into the middle of the pivot point. You don't need it very large in diameter, 1/8" is all you will need. I have made long drill bits for this exact purpose before, get a piece of bar and silver silder a drill bit to it when holding one end in the 3 jaw chuck and the other in a drill chuch in the tail stock.
Countersink the end where you are putting the grease nipple so the end is protected and thread it for the nipple. If its not clear, i can try and explain it better.
Sorry that i answer things and cause you more frustration my bad!

Tazza said:

It is a silly design isn't it? At least the attachments i have seen without grease nipples ran nylon bushings.
You can make it greased if you want to. If you have access to a lathe, chuck it up and drill a hole from the end with the washer, drill it so its just over half way though. Drill one or two small cross holes half way down at 90 degrees to the one you did before. This will allow grease to run from the end of the pin down and into the middle of the pivot point. You don't need it very large in diameter, 1/8" is all you will need. I have made long drill bits for this exact purpose before, get a piece of bar and silver silder a drill bit to it when holding one end in the 3 jaw chuck and the other in a drill chuch in the tail stock.
Countersink the end where you are putting the grease nipple so the end is protected and thread it for the nipple. If its not clear, i can try and explain it better.
Sorry that i answer things and cause you more frustration my bad!

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I checked the Operator's Manual and there is no mention of how to lubricate the pivot points on the bucket. However, there is a footnote that says
"A bucket is normally stored with its two pins and their washers and securing bolts. Remove these pins, check the bushings in the bucket".
That's it... nothing more. I guess one is left to assume from that one footnote that the bucket should be removed from the dipper when not in use and stored in some location along with its pins and washers. Although the instructions do not specifically reference lubricating the bucket pivot pin and the cylinder extension pin, I guess these need to be packed with grease upon each use (assembly of the bucket to the dipper).
I can tell you this for sure... in the roughly 20 years I've owned this machine I have never once removed the bucket or greased the bucket pivot points. Small wonder they are both frozen (rusted) solid and had to be cut out rather than driven out with a drift.

Jyuma said:

I checked the Operator's Manual and there is no mention of how to lubricate the pivot points on the bucket. However, there is a footnote that says
"A bucket is normally stored with its two pins and their washers and securing bolts. Remove these pins, check the bushings in the bucket".
That's it... nothing more. I guess one is left to assume from that one footnote that the bucket should be removed from the dipper when not in use and stored in some location along with its pins and washers. Although the instructions do not specifically reference lubricating the bucket pivot pin and the cylinder extension pin, I guess these need to be packed with grease upon each use (assembly of the bucket to the dipper).
I can tell you this for sure... in the roughly 20 years I've owned this machine I have never once removed the bucket or greased the bucket pivot points. Small wonder they are both frozen (rusted) solid and had to be cut out rather than driven out with a drift.

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I'd put money on the fact that if it was used commercially, they wouldn't take the bucket off every use! It will stay on and removed only if they needed a different bucket. The more you remove and store something like that the higher the chances are that you will get dire in the grease and cause more damage anyway.

Tazza said:

I'd put money on the fact that if it was used commercially, they wouldn't take the bucket off every use! It will stay on and removed only if they needed a different bucket. The more you remove and store something like that the higher the chances are that you will get dire in the grease and cause more damage anyway.

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It's been over a month since my last post and I wouldn't want you guys to think I've just dropped the project. I had to put the project on hold while I finish a kitchen remodel I started long before I started the loader project last spring. I hadn't counted on all the problems with the backhoe so the now totally disassembled backhoe has been packed away in the shop until next spring while I finish the kitchen.
Naturally I'm designing and building my own cabinets... you wouldn't expect me to take the easy route and buy cabinets would you?

Jyuma said:

It's been over a month since my last post and I wouldn't want you guys to think I've just dropped the project. I had to put the project on hold while I finish a kitchen remodel I started long before I started the loader project last spring. I hadn't counted on all the problems with the backhoe so the now totally disassembled backhoe has been packed away in the shop until next spring while I finish the kitchen.
Naturally I'm designing and building my own cabinets... you wouldn't expect me to take the easy route and buy cabinets would you?

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Someone must have took out the origial gun drilled pin and replaced it with a solid one. Thomas can't be so silly as to run it dry??
At any rate find a way to get grease in there, there is no option imo.
Skidsteer.ca

skidsteer.ca said:

Someone must have took out the origial gun drilled pin and replaced it with a solid one. Thomas can't be so silly as to run it dry??
At any rate find a way to get grease in there, there is no option imo.
Skidsteer.ca

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I have been checking, every time i see a new post in the Thomas section i think ooh, he may have more news, but not always
Its a shame its not all finished, but i'm sure you will attack it when time allows.