can motor replacements

You will want to get or make a gear puller. Micro Mark sells them. I had some square tubing so I made my own.

The trick will be to reinstall the gear without bending the shaft. They are a very tight fit.

Sometimes I have resorted to opening up the hole slightly so it slides on and using Super Glue to retain it. If you bend the shaft the motor is essentially shot as its near impossible to get it back on axis.

Pete

You also have to insure the shaft is supported at the opposite end for pressing the new gear back on, sometimes difficult with certain motors.

For the cost of the motors, I would just replace them, save yourself the frustration. The gear on the thin armature shaft is pressed on at the factory, and difficult to remove and replace the gear without bending the shaft, or gouging the bushing with out special tools. The motor you want is 600-8008-105, or 600-8903-120.

You may want to contact Frank Timko.  He seems to have the ability to remove worm gears and re-install them on new motors.  I had sent him, a few years ago, an odd ball Weaver motor, worm and mounting.  He did an excellent job of installing the old worm on the new motor.  He also supplied motors with worms and mountings for a set of Weaver E8's that I upgraded.

I'm with Chuck if the motors are available.  The 600-8903-120 he mentioned is unavailable on the Lionel site, but the 600-8008-105 is for $8.  OTOH, the motor doesn't look like the right one...

Dunno about Lionel motors, but the MTH gears are held with Loctite, and it takes a special fixture and heat to change them out.  A tricky operation, because you cannot drop the motor and expect it to work afterward.  We get only ten years of continuous operation out of an MTH motor gear, but that is eight hour days!

You could also contact Brasseur Trains, I recollect that some of the early Lionel locos had the same motors and gears as the KLine ones, esp. those used in the MP15 and S2 switchers. If you email them they respond promptly about requests for parts questions, in my experience. 

Cut it with a dremel disc, from near shaft tip towards the motor, parallel to the shaft, but don't hit the shaft. When you are at 3/4-7/8 of the way thru, stop and try to break the slice off using a screwdriver. This break usually shocks the gear, breaks along the thin layer next to the shaft too(if you're lucky), and it often loosens enough to use pliers, otherwise you need a second cut on the other side, and a bit of light grinding to get it thin enough to split it. But don't grind the shaft!

  Top cutters hold small gears well and can split some brass gears on their own, or tapping with a hammer.(top cutters are kind of like side cutters, but blades are 90 degrees to the handle)

A chisel would work too. 

Why would you go through all the effort to pull and reinstall gears for a $8 motor.

The other part number is: 6208857100 for diesels.  The 8008-105 is for 4-4-2 starter set.

I thought that was the 12 tooth pinion gear he wanted to replace, also the gear is too small.

Just ran across this issue, the gear on the K-Line motors have a different tooth count.

GGG, the other part number was listed as unavailable on the Lionel site, so the first trick would be to find it.

The 620-8857-100 is a nine tooth gear used in modern trucks, the 600-8008-105 has a ten tooth gear and was used in earlier diesels with truck mounted motors and steamers. 

 The early Lionel and K-line trucks would interchange with each other, but not the newer ones that I have tried.  Maybe we could ask for a pic or product number to move things along.

Bill

I ran across a fairly new K-Line truck and the RMT trucks that are direct K-Line copies, both have the 12 tooth gear in the truck mounted motor.  I have a Lionel locomotive with truck mounted motors here for repair now with the 600-8008-105 motor that has a 10 tooth gear.

The part 600-8005-105 comes up as a mounting bracket on the Lionel site.

John, Then that is the motor he wants.  He asked for 10 teeth, the one I posted is also available.  Chuck posted one part number no longer available.

Bill thanks for the clarification, I know I had to replace a diesel recently and it used the 9 tooth version.  Come to think of it I have used the steamer one on some of my older Lionel Diesels, when I added additional power trucks.

Wonder where the original poster came up with the 12 tooth.  G

The K-Line motors have 12 teeth.

Made the correction.

Heat the gear up to about 200F...carefully?

This also decomposes the Loctite.

heating the gear up will also melt the

plastic bushing

Thought I heard that extreme cold would also help debond locktite...."freezer"?

Its a press fit. I doubt loctite was used. The gears can be removed with little problem. Its reinstalling them that takes care.

Pete

to install your gear put the motor in your freezer for about 20minutes or so then heat your gear to about 175-180 degrees --the gear should slide right on

axels on jets are put on this way

And gears and bearing races on BMW motorcycles 

That is because the part # is 8008 not 8005.  G

That must be a big freezer for the Jet:-)  G  Just Joking! 

don't know about all of them but the last off the sport models did" F86's"

And that's why flying is so dang expensive...yeah, they tell you it's the jet fuel, but it's really the huge freezer I bet!