Pin Hole Too Big

[Mike in Dewey]

I just bought my first tractor (Kubota L39 TLB) at a Lyon & Son auction and made a mistake. I thought I壇 looked over everything pretty well but missed the pin-hole elongation on the swing frame that the alleged mechanic covered up by welding a large fender washer to the top of the pin and then painting it all Kubota-orange. The manufactured 1-1/4 bored holes (top and bottom) now have nearly a 1-3/4 outside diameter. So now the questions.

Should I cut my losses early and simply purchase a new swing frame and pin roughly a $1000 investment in parts, or do I take the assembly to a machinist to attempt a fix? And, if the latter, should the pin holes first be filled with metal weld and then rebored, probably sized for a sleeve bushing, or do I attempt to cold-weld (JB Weld or metal epoxy) a top and bottom sleeve bushing (1-1/2 OD) or flanged sleeve bushing (again 1-1-2 OD with the flange (1-3/4 OD) being closer in diameter to the elongated holes), or do I have the holes resized for a high load, sealed ball bearing (the one I found has an OD of 2-9/16??

My concern with filling the holes first with metal weld before having them rebored is that the resulting heat may make that area of the frame too brittle and the inherent voids in the weld may compromise the needed strength. My concern with the cold weld options securing sleeve bushings is that the fill won稚 be strong enough for the imparted forces. My concern with making the holes bigger for a ball bearing (or even leaving them the size they are) is losing the meat of the frame and possibly making the whole assembly too weak.

And as a side, what would have caused this in the first place? The other (left) side frame hole and pin look good as new. Why would one side get so buggered up and not the other? Was this likely caused by the original swing frame being defective or is this type of wear to be expected?

Any knowing experience or intelligence would be greatly appreciated.

 

[aarolar]

Proper repair would be to bore to a larger size and bush it with a interference fit bushing. Any proper machine shop will be knowledgeable about this procedure.

That being said welding it up shouldn't cause any of the mentioned problems it is made of a mild carbon steel not any time of high carbon that should be hardened by heat.

 

[Mike in Dewey]

Thanks, aarolar. My knowledge of bushings (McMaster-Carr) indicates that the available 1-1/4" ID bushings are all 1-1/2" OD. With the oversized holes now being 1-3/4" OD (roughly), is the correct procedure to put a bushing in a bushing to get to that diameter, or are thicker-walled bushings available, or do I simply leave it up to the machine shop? If possible, I'd like to do this just once and eventually pass on this tractor to someone that doesn't have to worry about this particular issue in the future.

 

[JimRB]

A machine shop can make a bushing in whatever OD and ID is needed. A welder might just cut out the worn out bushing and well in a new bushing. Guys build their own backhoes and buy bushings to be welded so brand new bushings in the correct size are out there.

 

[KWentling]

I would recommend taking it to the machine shop and let them give you repair options and a price to do it. I've repaired a few in my 30 years as a machinist and we always welded them up and rebored to standard, but that was on larger machines and those bores received hardened bushings just like when new. I imagine this did not have bushings? I wouldn't try fitting bearings. Hardened bushings would be a better fix. Very important to keep all those pins and bushings well greased!

Kim

 

[aarolar]

As JimRB said the machine shop will make custom bushings to fit the need.

 

[Mike in Dewey]

Thanks to all. I'll take some drawings to a local machine shop and get an estimate. If it's less then new, we'll put them to work. The holes within the swing frame did not have bushings and the pin is stationary within them. There is a bushing within the swing cylinder's rod knuckle, which is supposed to rotate about the pin, and that seems to be well lubed. Perhaps at some point during its 720 hour life the assembly seized resulting in the damage. I guess it doesn't really matter; however, I'll likely remain annoyed with Ahern Rental for purposely hiding the problem rather than properly addressing it, and not disclosing the issue before they sold the tractor. On the positive side, I'll get to break out the wrenches, get a little dirty, and add to my knowledge of this part of the whole.

 

[2458n]

That is why you go to auctions early and really look over what you buy. The quick fix by a rental company is a standard practice for them. Nothing to get upset about. That is the way the game is played. I am sure you held a little back when bidding to cover for things like this. Give it to the machine shop and get a bid for the work- they do this stuff every day.

 

[Mike in Dewey]

That is why you go to auctions early and really look over what you buy. ... That is the way the game is played.

2458n - There could be an entire discussion on the expected honesty of one that sells something to another. We all understand that if it shines it sells, and that the buyer should beware, but if the seller purposefully hides a defect, if they sell you a house and know that the foundation is cracked but is also well concealed, or put sawdust in the transmission of that old Buick to quiet the grinding gears, or remove a safety because it was annoying to them, or do whatever else they can to obtain a higher price than the item deserves, is not that fraud if they are aware of the issue and it isnot disclosed? Is that what you are suggesting is the proper way to play the game?

In this case the seller was using an auction because they knew that it was the most expeditious and economical means to eliminate a large quantity of depreciated assets. Buyers expect to pay less at an auction because the sellers are willing to accept less for several reasons that make financial sense to them. One of those reasons should not be, and never have I seen it documented, that an auction grants the seller tacit authorization to freely commit deception. I absolutely understand that items are sold as-is, but that definitely does not mean that if the seller knows of a significant issue regarding most anything that is sold, whether it is a dealership or an auction house or a private owner in another state, that they get to remain silent about expensive or safety related issues of which they are certainly aware.

As-is means that the seller is not aware of anything beyond the obvious. Ahern Rentals, which owned and serviced the tractor I bought, is one of the worlds largest rental businesses and certainly tracks the maintenance and problems and everything that needs to be done for all of their capital goods, just so that they can continue to rent the items and maintain their return on investment. Their records (which they did not share) knew that the tractor they were attempting to sell had problems that they had willfully concealed, and also knew that if discovered or disclosed that the offering price to buy would be reduced. They would be stupid to rent a tractor to a business, that was also expecting to generate a profit in using that equipment, if they knew that he tractor was likely to fail, thereby costing the renter money along with bruising both of their own good names, and I doubt that Ahern is stupid. No, the welding of a large washer over that oversized hole and painting it orange was done only for the auction crowd, and it was only done to hoodwink the potential bidders and hope that the winning bidder would not have the gall to demand fairness. As-is never has and never will mean that the seller gets to legitimately paint over known problems that prospective purchasers are not expected to see.

If everyone was well aware that a business or a person was apt to conceal known flaws related to a large percentage of that which they sold, who would buy their products except for probable scrap or possibly parts? Who would ever purchase and sit on such a machine that would likely have hidden a weakness that could cause them unanticipated pain or financial misery? The answer is, no sane individual, so I reject the premise that one should expect to repair an unknown failure just because an item is purchased at an auction. If it is missing a bucket, absolutely, that is obvious enough. If there is a puddle of oil under the transmission or the tractor does not start or the hydraulics do not work or a tire is flat - ya, those you are expected to see, and by offering a visual inspection of the property those such things are being disclosed. But if the one offering the goods goes out of their way to hide or obscure a problem, then that certainly sounds like fraud and not what we should obligingly accept from any seller. Sure there are some and maybe many out there that thrive and profit in using deceit, but we usually term them crooks and the civil society is supposed to, eventually give them their due justice.

Yep, I believe in the Golden Rule and expect mostly good in this world and occasionally seem to be charging windmills. And yes, I have already contacted the Clark County, NV District Attorneys office to see if they would like to investigate possible criminal activity, and I am looking into civil litigation (small claims court). Nothing ever got done that was not started and others should not be too surprised if their expectations are low and that is exactly what they get.

 

[LD1]

I agree on talking with a machine shop or two and explore your options.

Do you have any pictures of the parts needing attention. I have done alot of pin/bushing jobs on sloppy backhoes. But am unfamiliar with the L39 setup. Specifically, are we talking about a small piece that can be taken off and taken in to be machined? or are we taking about practically taking everything apart to get to a sizable 150# chunk of metal?

Pictures would do me wonders.