My pin bosses have worn threw the bushing and have egged out the bosses. I received new ones from Bobcat. Any tips for removing the old ones? Are they only welded on the outer edge? Which welding rod to use? I can mig, stick or tig weld them, what's the best method? It also looks different having a lip on it unlike the old one does not. Trying to get pics up soon I also have the seals which look like they just sit on top of the pin boss. Jeff
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oooooh, you have a big job ahead of you.
I used a plasma cutter and grinder to do mine. It's hard to get good access to cut what you need to. From what I can remember, I ground and plasma cut the part that the bushing goes into, I think it was welded to the bobtach, so it needed to go. I gouged out all I could with the plasma and used the grinder to ge tthe last bits.
I used a thin blade in the inner end to cut the welds, I used the plasma again to cut the welds around the boss, it doesn't matter if you cut a little more material out of here as you simply weld it back up later. The only part to ensure you don't enlarge is the end where the boss slips in from. It is profile cut to be a pretty good guide then welded in place.
When they are both out, install your bushings and slip the bosses into the bobtach, attach the bobtach to the machine, the pins will help locate the bosses in place for welding. Remove a battery cable and then do your tack welds. Ensure it moves up and down freely. Weld it SLOWLY, I got one a little hot and it warped enough to bind a little bit.
I used a stick welder as I get far better penetration with one than I do with my MIG.
I can get you pictures if needed, but you'll need to give me a day or two. If you want some, look up my profile and send me an email. I have a bobtach with the bosses cut out already with new ones made I just need to weld them in place. It will show you what was removed and an idea of how.
I used a plasma cutter and grinder to do mine. It's hard to get good access to cut what you need to. From what I can remember, I ground and plasma cut the part that the bushing goes into, I think it was welded to the bobtach, so it needed to go. I gouged out all I could with the plasma and used the grinder to ge tthe last bits.
I used a thin blade in the inner end to cut the welds, I used the plasma again to cut the welds around the boss, it doesn't matter if you cut a little more material out of here as you simply weld it back up later. The only part to ensure you don't enlarge is the end where the boss slips in from. It is profile cut to be a pretty good guide then welded in place.
When they are both out, install your bushings and slip the bosses into the bobtach, attach the bobtach to the machine, the pins will help locate the bosses in place for welding. Remove a battery cable and then do your tack welds. Ensure it moves up and down freely. Weld it SLOWLY, I got one a little hot and it warped enough to bind a little bit.
I used a stick welder as I get far better penetration with one than I do with my MIG.
I can get you pictures if needed, but you'll need to give me a day or two. If you want some, look up my profile and send me an email. I have a bobtach with the bosses cut out already with new ones made I just need to weld them in place. It will show you what was removed and an idea of how.
.....here is another method using a torch , the boss tube sticks out the ends and is exposed between the ears that they are welded to , cut all the tube you can as close as you can then split what is left of the tube inside the ears into quarters , then wash the sections of quarters away and use a punch and hammer to knock them off
Do I cut the welds where the two long welds run the same direction as the pin? Between the two welds is that the boss or a plate over the boss?
frogfarmer
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Well now Im confused. Any chance we can get a pic or two?
I got lost too --------you must not have the new bearing or the bearing holder weldment in you hands yet , if you did you would see what it is that you have to cut out ---------- or -------you are talking about the boss bushing on each side the tilt cylinder pin ???????
I did send a pic to Tazza. I do have the new bosses in my hand. Looking at the boss that is still in the bobtach it appears to be welded on the end only...but there are two welds that run down the bobtach that look like could also hold the boss. Not sure if cutting the weld might help in removal of the boss.
I'm calling the"Boss" the part that the bushing goes in.
I think they need to know whether it is the bushing where the tilt cylinder mounts on the bob tach or the two where the bob tach mounts on the loader arms.
It where the loader arm go
http://tinypic.com/view.php?pic=2klhf4&s=5
If you copy and paste the second link it will open the photo. Sorry trying to get this pic thing working.
OldMachinist
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To make a link turn blue you need to hit the enter or space key after you paste it or use the create link icon in the editor menu.
To add a image to your post open the image where ever it's hosted then copy and paste it to your post.
OldMachinist
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If you don't have the menu go to your forum profile and scroll all the way to the bottom. Check the box for "Use HTML editor". Then click update user information.
I think they may have given you the wrong weldment , I would recheck with the dealer , I am not saying you couldn't make that work , maybe that is the only way they sell a replacement for the what you have now , that lip on the end makes me think is the newer style where you have an older style Bobtach , I know when you replace a complete bobtack they give you a newer style , there is no more old style bobtacks , the new one is an upgrade from the old and styled differently but interchanges ---------- you will have to cut those welds length ways
http://i44.tinypic.com/654dba.jpg Another test. Also I gave bobcat the part number for the 1.50 inch out of my 1998 service manual. I guess it superseded.
that's a better pic , that one should be easier than what I was thinking you had , you do need to cut the weld to the left of the zerk fitting and along both sides length wise and both sides the ear to the right of pic ------------------ I'd ask about another weldment for an older Bobtach -----------years ago I helped a guy with a 7753 and 1.5 pins that was always breaking the pins , that machine came with 1.5 at first then went to 1.75 pins , we replaced the weldments of the Bobtach with the 1.75 size and we drilled the boom to accept a 1.75 Contruction Tool Part a-taper bushing and upgraded his machine
I just looked at the pic again and I think it looks like the O.D. of the hub around the outer end of the new weldment looks to be the right size but the O.D. of that new one behind the hub looks smaller than whats on your Bobtack , if so when you go to weld that in there is going to be a big gap along the lengthwise weld , what you think ???? ----if it were you could always lay a piece of flat bar over the gap and weld it on both sides
