There are adjustable reamers available too but not sure if they go down this far in size. They can be nice to have on hand at times.
Roger,
The K Line version of the service manual also lacks information on the 681. I had to use the motor breakdown for the 736, which also used the 681-100 motor.
Jim, the dealer I bought from may have not even known if the bearings I bought were REALLY OEM. I get wrong parts frequently from different people. What makes repairing the 681 tough is the Greenberg book does not cover it, only the 671.
Roger
Glad to hear you've found a solution. That's a good point that the bushings might not be the correct ones. I went a similar issue while working on a 681-100 motor. I wanted to replace both front and rear armature bushings, so I ordered the 671M rear bushing that my service manual shows for the 681-100 breakdown.
I didn't pay any attention until I received the bushing and saw that it was not correct. I've never worked with any F3 axle bushings, so I can't say if there is an issue with mixed up part numbers in that case.
The reamer tool has arrived here already. It will pass through factory installed bearings but will not pass through uninstalled, or installed by me bearings. So the next step is to use the tool as designed and see what happens.
I just used the 188.5 reamer tool and it works beautifully. I actually probably could use a 189.0. So this will solve my problem. Who knows what the bearings I bought actually were for? They could be 671/2020 turbine bearings as well.
Thanks for the help. I may invest in other reamers in the future.
My bearings came from a company that sells old lionel, flyer and some other parts. They claimed these were OEM bearings.
You did not indicate which company supplied the parts. That is just as well. Everybody makes an error from time to time. Not that long ago I ordered a dozen worm wheels (gears) from a long established, well known, well respected Lionel parts dealer. They should have all been the same, but I received a mixture of two different styles. So it is possible that you were sent the wrong bearings. It is also possible that Lionel made an undocumented change to the bearings somewhere along the lines.
Your posts indicate that the bearings are too oversize for the hole in the truck frame, as my original post suggested. I, (and probably others on this forum also), have never had to ream out bearings after installing them. If you need a lot of force to press the bearings in, then they are very much oversize. Your options include getting bearings from a different vendor (recommended), drilling out the truck frames to accommodate the oversize bearings (NOT recommended), or having bearings custom made for your application. (I made a custom set of bearings for a 681 where the bearing holes in the frame had worn oversize).
To narrow down your problem, please post the exact outside diameter of a new, unused bearing, and the nearest drill size that will fit, even snugly, into the truck frame.
Larry
I have ordered a reamer. Because this is a learning truck, I decided to press a couple wheels on. I accidentally went a bit too far and the bushings were pushed in deeper too. I had originally left them out further a few thousands to get better wheel to chassis clearance. When the bearings seated all the way in the axles locked up tightly. Even after I removed the wheels the axles would not rotate anymore. It seems that even pressing the bearings a little bit compresses the inner diameter. This is really confusing.
I remember a while back when a certain vendor sold 681 axle bearings to a friend of mine he told him that he would have to ream them out to size after pressing them in. Anyone else done this?
I had called Carl Burchett and talked with him about it. He had not seen it before.
If reaming bearings was commonly required, I would expect that someone would have put together a kit by now. Please let us know how everything works out.
Great thread guys! It has been most helpful. Larry, thanks for the tool tips I bought a reamer and will try that.
CW and Bob, thanks for helping out. The Hobby Horse tool books never mentions that you may need to ream the bearings to size afterwards. I had called Carl Burchett and talked with him about it. He had not seen it before. These are the first bearings I have done.
Bob,
In an ideal/perfect world with precision bored holes, precision manufactured axles, and precision made bearings, you probably would be right. Are toy trains made this way? Nope. Holes are drilled, not bored or reamed. Axles may be well made, and soft brass bearings may be satisfactory for the use they will get. Castings may have hard and/or soft spots that may affect the pressing in of the bearings. Added together, the bearings would probably distort to some degree as they are pressed in.
In the end, your suggestion would probably work and maybe someone will try it and report the results.
Larry, I can see that the inside hole through the bearing would be non-circular if pressed into a hole in the casting that is not circular, or if the outer shape of the bearing itself were not circular. But, if they are both circular, I expect the center hole simply to be slightly smaller and not particularly distorted.
Bob Nelson
A reamer is used just like a drill. Drills, because of how they are made, do not drill truly round holes, but rather a 3 lobed hole. A reamer is used to open up a slightly undersize hole, and to make the hole round.
Here is a .1885 reamer that should do the job for you.
I got a caliper tool and measured the axles. The axle is 187.5. The best I can see on an original factory installed bearing still in a truck that had never seen the track is 188.5. So it needs to be a bit bigger. Thanks for the web site I will see if there is a reamer that size. Keep this in mind for any future 671/681 engines because it is the same axle used.
So how is the reamer used? You don't punch out a bigger bore with it do you?
The result of that process would still be an out-of-round bearing caused by the bearing deforming as it is pressed in. The bearing O.D. should be machined, sanded, or filed to be a light press fit, and then it will not deform when pressed in. Barring this, the bearings can be either carefully hand reamed, or if a drill press and decent vise is available, the truck and bearing squared up in the vise and 2 bearings reamed at once, in line.
Single reamers (as well as most any other machine tool) can be had from MSC Industial. These are 3/16" reamers that would probably be the correct size for the job.
This (untried) process might work: Subtract the the inside diameter of the bearing when pressed into the chassis from the inside diameter of the bearing when loose. Add this amount to the inside diameter of the bearing when loose and drill the loose bearing out to that diameter. Then press the bearing back into the chassis.
Gotcha!
I looked on the Harbor Freight site. I certainly could have missed them, but I did not see reamers in the size range that we would probably need for Lionel trains. Most of the reamers I see on the Micro Mark site are tapered for hole enlargement.I did see a set of six for $33.50, a set of seven for $54.50 and a set of fourteen for $97.95.It's not clear to me how many pieces in each set would be useful for trains. So where would one buy them?
I am also curious about how one would use the reamers. It doesn't seem that high precision work would be that well done by hand. The Micro Mark seven piece set indicates they are to be used in a milling machine, lathe, or drill press. I have a drill press, but I do not think it has the precision of a lathe or milling machine.
I can only recall one reference made by Lionel to reaming bearings. According to the Lionel Service Station manual, whistle motor armature bearing are line-reamed due to the high RPM of the whistle motor.
Thoughts?
Sorry about the confusion. It is actually a "hand reamer", the confusiom came from the fact that a short portion of the lower part of the reamer is slightly tapered under the finish size so it will start and act kinda like a centering guide for the final cut.
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I have the same thoughts about a tapered reamer.
I do not have any real expertise with reamers, and am looking to learn.
I understand that properly used, a flat reamer would give superior results to a drill bit.I do not understand why a tapered reamer would be superior.By the reamer's very nature, wouldn't the bearing surface be tapered, leaving only a tiny portion in contact with the rotating axle? Then in turn, wouldn't that tiny portion wear quickly? I have tapered reamers, I use them to enlarge holes in thin materials.
A good tapered reamer used with a tap handle is an excellent investment for these types of jobs. They don't need to be the hi-end expensive ones either, just remember to use a couple of drops of oil to help the reamer do it's job.
Thanks for the help guys. I think I see the big picture here now. I am going out to get a caliper tool. May look into the reamers. Definitely need a full set of drill bits.
Cw, the fist one I installed I did have the axle sitting in it to help with alignment and the axle was stuck afterward. I guess installing both bearings and then reaming them out is the best solution. A 3/16 drill bit seems to be near perfect for this.
If I had any 2333 axles or bearing on hand, I'd be glad to check, but unfortunately, I do not.
The holes in bearings / bushing have to be slightly larger than the shaft that rotates in the hole, otherwise it will bind, as yours is doing. For example, I measured a NOS 2343 axle to be .3085 inches in diameter. The opening in a matching NOS 2343 truck bushing measured to be .311 inches, so the difference is about .0025 inches.
The drill bits I try to use to protect the holes are usually just a bit over the axle diameter, on the order of magnitude of a few thousands of an inch.
I have a nice set of drill bits in inch, number (1-60) and letter. I am careful to clean the bits and put them away in their case after use. So I've had the same set for years. (I have broken some of the smaller ones, in the 55 to 60 range.)On occasion I have also used the drills as a poor-man's gauge to measure the diameter of holes.The number set turned out to be a very good investment.I don't know whether I've ever used the letter drills.
Roger, If you don't have a Harbor Freight near you what about ordering an appropriate sized reamer on-line or even checking out Amazon, Micro-Mark etc. Granted it will delay your project a few days but the accuracy of the reamer vs a drill bit could make it worth the wait.
While I have not had this problem on 2333, I have run into similar problems installing bearings in other places. To avoid the issue, I like to put the shank of an appropriately size dril bit in the hole to keep it open. Obviously, if you follow recommended practice, you could only do this on one side.
I agree with TrainLarry, you can push the axle through the bearing. I've done it, and I do not think the minor scoring that is created by the knurled section is anything to worry about. I would try to always push the axle through the same side, and with the knurling in the same position. You should be able to feel the ridges of the axle catch in the tiny grooves cut into the bearing.
I am always interested in reading the solutions other folks have.
My bearings came from a company that sells old lionel, flyer and some other parts. They claimed these were OEM bearings. The bearings would easily pass an axle before installing, then not after pressing in. I don't have a micrometer here yet, need to get one. It appears that one side of the axles is thicker than the other side.
Rob
It sounds like the bearing is a bit oversize for the hole and is getting squeezed shut a bit when it is pressed in. It should not take too much pressure to install the bearing. There are issues with aftermarket bearings not fitting properly, so you may want to try getting bearings from another supplier to see if they fit better. If you have a micrometer, measure the O.D.of the original bearings, and compare to the replacements. The measurement needs to be exact, as even a half thousandths of an inch larger will make for a tighter fit, thus distorting the axle hole.
In the end, you may need to install the bearings first and ream them to size if necessary. Install the axle through one reamed bearing, through the worm wheel and out the other bearing. You may need to lightly hammer the spline on the axle through the first bearing. Do not worry about the spline on the axle damaging the bearing, as it will just scratch it at the most.
I understand that, but you cannot do that with F3 bearings. You have to install one side first, then push the axle through the gear and into that bearing, then install the other bearing over the exposed axle. You cannot ream the bearings and then punch an axle through them as the part that holds the gear will damage the bearing.
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