Repair question

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I have a compact tractor with a loader, and after the last 35 or so years some of the holes in the loader frame that hold pins have elongated.What is considered good practice for repairing this? Does one build up the hole and then drill it out, or ream it out?  Or does one weld in a hardened bushing which the pin goes through?The pins are about a half inch in diameter, and hold the frame a little more rigid, but pull out so that they engine hood can be lifted.Thanks for any replies to this seemingly basic question.Last edited by linuxbird; 09-07-2015 at 10:35 AM.Reason: Typo
Reply:I think all the methods you mentioned and several more can be good, depending on the situation. Pictures showing the construction and givning an idea about how these parts are loaded might help.
Reply:Very small tractors usually have holes bored through structural steel. A bit larger might have bushings of DOM (drawn over mandrel) tubing. Then you get to machined weld in bushings fitted with pressed in place bushings. A further refinement would be the addition of seals to hold grease in, dirt out. What you have will dictate what repair technique is best.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:I can try to do some pictures. But the holes I'm worried about first, are probably the easiest. They are in something just shy of 1/8" steel, and they are simple holes through the steel. A pin goes through them on both sides of the loader effectively adding a cross member come which is removable. It can be removed by either pulling one pin and swinging the crossmember, or pulling both pins and taking the crossmember off.  Vibration and racking of the frame has caused the enlargement and elongation of all the holes. It has also caused the narrowing of the pins which are approximately half inch diameter steel.Since I finally have electric welding equipment, I figured I would explore what my options are. With oxy acetylene, I would be inclined to fusion weld a bushing in place, or to braze a bushing in place, or to build up (fusion) material narrowing the elongated holes, and then grind it to an approximate size for reaming.Other parts of the loader, for example where the pins are for hydraulic cylinders and for pivoting the loader, appear to have hardened sleeves welded in place.There are numerous cracks and weld failures in the loader, and I will undoubtedly be looking for guidance on repairing them, but I thought I would tackle one of the simpler problems first.Last edited by linuxbird; 09-07-2015 at 05:54 PM.Reason: My stupid spell checker keeps changing spelling on me
Reply:The pin holes, I suggest boring out with a hole saw, perhaps 1-1/4" Fill the space created with a disc of the same diameter. Bore the patch using a drill press on slow, with oil first from a small piece. Center the hole in the waste piece on the original position of the pin. Tack weld or clamp well over the worn hole to contain the hole saw. Using the slowest drill you can, cut your hole. Clean thoroughly with acetone & grinder. Weld your patch in. You know what welding technique you are qualified to use. I'd favor MIG, or TIG. After it cools open the center hole to original diameter. I've tried numerous times to weld in a hole partially, then ream. It didn't work. It's not likely the welded in bushings are hardened. Machines using hard surfaces to wear likely have bushings pressed into their bores.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:If you're describing the crossmember at the front of the tractor, running between the loader frame arms,then drilling out to next size (5/8") and using larger pin would be easiest.The other methods described would be appropriate for cylinder and loader arms/bucket, larger greased pin fittings.Just my thoughts,DBLast edited by labparamour; 09-07-2015 at 08:05 PM.
Reply:If yours is like the blue one in the pic he is right in that just drilling a larger hole for a larger pin is the fastest and easiest way and is comonly done. If you want a perfect fit welding the holes shut and re-drilling will give a slightly more acurate finnished job. Most people would never tell the difference, but perfectionists will notice as oversizing the holes could result in slightly off center holes.Yeah, I know, but it'll be ok!Lincoln Square wave 255Miller Vintage mig30a spoolgunThermal Dynamics Pacmaster 100xl plasmaSmith mc torchEllis 1600 band saw
Reply:A 5/8" bridge reamer would make that a cake job.My name's not Jim....
Reply:The repair is similar to the photo shown but there is less material in my case and if I were to enlarge the hole I would want to laminate a 1/8" or so patch to reinforce the area.If the hole were filled completely I would not expect having a problem drilling precisely.  BTW where does one buy inserts and bushings?
Reply:I have used DOM tubing cut on a horizontal bandsaw to make bushings. Be aware that welding changes the shape of the bushings. They will need to be reamed. I buy DOM at MAC Steel in Rutland VT, I think McMaster/Carr sells it.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:I ran into this same problem with a used backhoe I bought. I took some 1 1/2“ or 2“ round stock, drilled a hole in the center for the pin. Drilled holes for grease fittings, and welded the round stock to the backhoe. Also did the bottom pins on the bucket for the loader. Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400