Am I being misled?

I ordered a set of "good used" main bearings for my late model b. The bearings are from a used parts source that I have purchased from in the past and have had good luck with. I also ordered a crankshaft in the same order, with all the parts arriving in the same crate. The crankshaft is in immaculate shape but the bearings had a lot more marks/scoring on them than I had expected; however, I didn't see pictures of them before they were sent as they were still installed in the housings.

I've attached pictures of what I've got. I can feel all the marks with my fingernail, but I have very little knowledge on what is acceptable with these shim adjustable bearings. I sent pictures to the seller who told me that they are usable (he did offer a refund if I don't want to use them so I can't put too much fault on him). So, I'm looking for other opinions from the experts on here. Can these marks be cleaned up with some 1000 grit sandpaper or am I not getting good info from the seller? Thanks for any opinions.
 

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I'll have an opinion. It's a low RPM tractor, with low impact compression. They are serviceable, but - only just barely. The seller said 'good used' I would describe them as 'marginal used'. As I have no idea about the price between 'marginal used' and brand new, I won't advise on using them. Does the tractor get used every day? Plow often, grade, pull, belt drive? Is it a garage queen, parade only? I guess you could clean up the scratches a bit and use them, for a while. How much labor to replace after installation?
 
I'll have an opinion. It's a low RPM tractor, with low impact compression. They are serviceable, but - only just barely. The seller said 'good used' I would describe them as 'marginal used'. As I have no idea about the price between 'marginal used' and brand new, I won't advise on using them. Does the tractor get used every day? Plow often, grade, pull, belt drive? Is it a garage queen, parade only? I guess you could clean up the scratches a bit and use them, for a while. How much labor to replace after installation?
If it helps, I paid $60 for the full set (left and right). From this site it's $1000 new so... probably a deal even if they're marginal.

My bigger concern is that the crankshaft I bought has very clean journals and I wouldn't want the bearings to tear them up.
 
Used main bearings go right in the scrap bucket IMO.

I checked the price of new ones here, and yes, they are a tad over 1000 bucks. I find it hard to believe that is right.

I checked the price of mains for other tractors and the highest I saw was just under 200 bucks. Other JD models had higher prices than that though.

Is there something special about the JD bearings?
 
You need to decide if you are going to keep them or not. If I was the seller and you do any cleaning with Scotchbrite or sandpaper you own them.

Looks like new (AB4272R and AB4273R) may be about $425.00 new from JD.

Was the crank mic'd and checked to spec?
 
Jeez, at $1000 for new, I'd spend a few hours working them smooth first. Since they are fitted with shim stock, that's the next tricky job. As oils have gotten thinner over the decades, bearing clearances have gotten smaller. I guess, at the cost of new, get them shimmed to 3-5 thou each journal, run 30 or 40wt summer, and 20wt in cold climates and keep the torque load down through break in. You might get a few hundred hours out of them. Proper shimming, and proper oil weight will help. Maybe they can be replaced with only an oil pan gasket swap if things don't go well. Journal damage is pretty rare unless one spins. If it doesn't have an oil filter, get an after-market filter solution.
 
Only my opinion; those are not use scratches, they're tool marks. That said, if they mike the same thickness throughout, The scratches can be polished out, but it will require something the same diameter as the journals and used in a rotary motion, not in the same direction as the scratches/raised ridges.
After the bushings are made smooth and kept the same diameter from one end to the other, they can be assembled, plastigaged for clearance, and the proper shims used to obtain OEM clearance. Any remaining imperfections will soon wear smoother, as the bearings/bushings are softer than the shaft journals.
If that amount of work is acceptable to you, and worth the savings; then the journels mike to OEM specs as Jim stated, go for them IMO.
 
I wouldn't use them. If you Google John Deere B Man bearing, several choices show up. Steiner($139.99), Ebay, might try Lind Bros in Indiana for used..
 
Maybe they can be replaced with only an oil pan gasket swap if things don't go well.
You must have never worked on a or been around a Johnny Popper, they come out of the top. JD B in Resto Video shows rod access hole in first 20 seconds.
Edit: And as is obvious by my reply I was thinking rod bearings when the topic was main bearings. As pointed out by miangus in reply 13 there is a bit more to it than dropping an oil pan.
 
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I ordered a set of "good used" main bearings for my late model b. The bearings are from a used parts source that I have purchased from in the past and have had good luck with. I also ordered a crankshaft in the same order, with all the parts arriving in the same crate. The crankshaft is in immaculate shape but the bearings had a lot more marks/scoring on them than I had expected; however, I didn't see pictures of them before they were sent as they were still installed in the housings.

I've attached pictures of what I've got. I can feel all the marks with my fingernail, but I have very little knowledge on what is acceptable with these shim adjustable bearings. I sent pictures to the seller who told me that they are usable (he did offer a refund if I don't want to use them so I can't put too much fault on him). So, I'm looking for other opinions from the experts on here. Can these marks be cleaned up with some 1000 grit sandpaper or am I not getting good info from the seller? Thanks for any opinions.
I have worked on John Deeres a bunch.
They are not worn much.
I would use them just like they are.
Adjust them with the shims to about .003 and run it.
 
He is not talking about rod bearings. Changing main bearings in a two cylinder is not that easy. The right reduction cover comes off and the fly wheel on the left side plus getting the oil lines off inside the crank case. If you are going to use them, I would put them in the housing and shim to your crank. I would then take the housings and the crank to a machine shop and have them hone the main bearing to the final size.
 
He is not talking about rod bearings. Changing main bearings in a two cylinder is not that easy. The right reduction cover comes off and the fly wheel on the left side plus getting the oil lines off inside the crank case. If you are going to use them, I would put them in the housing and shim to your crank. I would then take the housings and the crank to a machine shop and have them hone the main bearing to the final size.
Ya that didn’t register in the ole brain. That probably did add some confusion, per my response to Doc.
 
You must have never worked on a or been around a Johnny Popper, they come out of the top. JD B in Resto Video shows rod access hole in first 20 seconds.
Edit: And as is obvious by my reply I was thinking rod bearings when the topic was main bearings. As pointed out by miangus in reply 13 there is a bit more to it than dropping an oil pan.
While I don’t usually do it just because it seems unwise one technically doesn’t need to change the oil to do rods or mains on a 2 cylinder. It’s a different way of thinking.

Oil is below both

Mains on a 2 cylinder are a bit more difficult but it looks like these have the replaceable insert style

AND YES THOSE ARE TOOL MARKS ON THE EDGE. They WERE serviceable. They are not any longer.

You can check them for clearance it is more difficult with a 2 cylinder it’s almost easier if you have the crank out to use your micrometer than plastigauge because you have to reassemble and it’s best to reassemble in the case so crank in and out until it’s right.

Or just measure with it out and order the bearing.

Again a totally different way of thinking than if there’s a line of 7 mains you are looking up at
 
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I appreciate all the replies. I have not mic'd the crankshaft yet, so the jury is still out on that.

I'm going to reach back out to the seller and see if he has another set he'd be willing to send out if I returned these. It sounds like they could be made usable with a lot of work but I don't believe that I have the tooling or experience to do it without screwing it up.

I did reach out to Deere about buying them new and despite what the website/dealer says, they are NOT available anymore. Apparently there's 1 dealer in the midwest that shows 1 set in stock but you can't actually order them.
 
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