Lionel 646 engine repair question

This may be the wrong group to post this question to however I was hoping that someone familiar with my problem may read this and be able to offer some advice. I have a 646 Hudson steam engine that I received with the train set that my Dad bought me in 1953. The set comes out now just briefly for the holidays, (space is limited). This year while cleaning and lubricating my equipment I noticed that there is a gear on the left side of the engine between the most forward and center of two of the six large wheels in the center of the engine that seems to wobble on the post it rides on. The post looks like its ok. It just seems to be the hole in the gear that has opened up considerably. This gear, about the size of a quarter was just "placed" on this shaft, however with the large wheels in place it is captive and cannot be removed from the shaft without removing these two of the six wheels in the center of the engine. The wheels seem to have been pressed on to their shafts and I don't want to force anything. The engine still runs well, however this gear wobbles as it idles between the two wheels. Luckily, the teeth on the gear as well as the teeth on the wheels are not chewed yet, but if this situation persists I'm sure they will be. I'm certain that this can only get worse if neglected. I have always maintained and even rebuilt many pieces of my set over the years but I've never disassembled an engine drive before. Can anyone more familiar with this kind of dissasembly please advise me as to how to go about removing these driving wheels without damaging the engine, the axles or motor assembly? Or if there is a more appropriate newsgroup I might present this question to I would very much appreciate being advised of that as well. I've tried rec.models.railroad but never received an answer. Thanks very much, Lenny

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Reply to
captainvideo462002
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If it has antique value then leave alone.

If not, ie wanting working order , what are the metals of the gear/shafts, brass, bronze , steel ? Just my halfpennyworth, know specific knowledge I would guess the wheels are interference fit to the shafts. Of course paint job would go but have you tried freezer spray on the shaft and hot air gun on the wheels?

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

a few close-up pics would help, uploaded to a site somewhere.

Reply to
N_Cook

It is antique but thats not important to me. I just want it running properly. I don't have picture capability. Lenny.

Reply to
captainvideo462002

I too have a 646 that my father bought for me back in the early 50's. I dragged it out of the closet and checked it out. Mine also wobbles, so maybe it is normal. Or it could be that this is the way these things wear out. As far as I can see, there is no abnormal wear, so I would leave it alone unless you get advice from an expert (obviously not me!)

CV

Reply to
Caesar Valenti

Good Morning,

I'm no expert on "O" gauge trains, but you can go to:

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which is the Train Collectors Association. I believe that their discussion forum (a link you'll find on the opening page) is open to the public. I think that you are referring to the idler gear, and yes, the wheels are pressed onto the axles.

Regards, Tim Schwartz Bristol Electronics

P.S. I think it neat that you still have your childhood toy and enjoy it!

Reply to
Tim Schwartz

It is antique but thats not important to me. I just want it running properly. I don't have picture capability. Lenny.

The wheels may be cast metal so no brute force to them

Reply to
N_Cook

They may be 'Mazak' and in imminent danger of crumbling to dust, so no severe heating and cooling. I have several vintage O gauge locos and other items which show cracking ad crystalisation in the castings. I once left a pre-war Dinky Toys racing car on a window sill in direct sunlight, a few days later it was just a pile of fragments except for the axles!

Ron(UK)

Reply to
Ron

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I never heard of "Mazak".Is this the equivalent of what I've known as "white metal"? It is non ferrous, absolute crap,very brittle and it will crumble if stressed. Lenny

Reply to
captainvideo462002

It`s an aluminium/zinc alloy, also called Zamak in the US, typically the material which mass produced diecast model cars are/were made. Early mixes lacked some kind of stabilising agent which led to it decomposing with age (crumbling and cracking with shiny crystals appearing in the cracks)

It`s not 'white metal' in that white metal is generally much softer and has a very low melting point - some varieties actually below the boiling point of water. Woods Metal is one such alloy I understand, generally used for casting war gaming figures etc. It`s also used in engine bearings.

Ron(UK)

Reply to
Ron

Yes, the terms vary, and the alloys change, but white metal - pot metal - Mazak - Zamac - (other) names generally refer to various alloys consisting primarily of zinc.

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The fine detail that can be reproduced/attained by casting small parts in pot metal is one of it's better attributes.

There are some parts that are made poorly with pot metal, particularly when the cross-sectional dimension is very thin. Some of the poorer grades/alloys deteriorate badly with age.

The better pot metal grades are somewhat similar to cast aluminum, but cast aluminum is more expensive both in raw material and casting costs.

Many grades of newer technology, reinforced synthetics are much more durable than many presently used grades of pot metal.

As far as making small parts, pot metal casting is a relatively easy process, which can essentially be done in a typical kitchen, or at a workbench.

-- Cheers, WB .............

I never heard of "Mazak".Is this the equivalent of what I've known as "white metal"? It is non ferrous, absolute crap,very brittle and it will crumble if stressed. Lenny

Reply to
Wild_Bill

Gosh, it's been since the latter '50s since I have worked on those. IIRC, the motor armature gear engages the top of that idler and the idler feeds the drive to the two drive wheel gears. I seem to recall that the gear on the armature was steel and the rest are die-cast. As others have mentioned, it is likely that the die cast parts are into the decomposition stage, so pressing the two drivers off the axles is fraught with them shattering. Assuming you could get the drivers off safely, and the idler is not in the final stage of decomposition, it could be bored out on a lathe and a brass/bronze bearing inseted. The drive wheels are then pressed back on the axles making sure to line up the splines to ensure that the 'quartering' is correct [angular position of the connecting rod pins]. I would suggest you go to the mentioned web site to see if new parts are available [wheels and idler] before attempting any repairs.

Neil S.

Reply to
nesesu

r

Having my friend at the machine shop oversize the worn hole in the gear and installing a bronze bushing was my intention, provided of course I could get the gear removed from the assembly. However after reading all the postings I'm starting to feel that maybe attempting disassembly of the motor even by an experienced Lionel repair person would likely be foolhardy. I've really been looking at this thing from various angles and another option has come to light. This gear wobbles because the hole has become somewhat eccentric. It also is apparently worn in thickness as it moves in and out slightly on the shaft. The wheels of course keep it from coming off the shaft. If some type of spacer could be installed behind the gear, (which would take up the end play and move it closer to the inside of the driving wheels thereby engaging the gears more fully), the hole of course would still be eccentric but this idler gear would run close against the insides of the wheels and it would run true. I tried to simulate this by holding a small screwdriver behind the gear and running the wheels The gear stayed in place and ran true. This is not the way I would really like to do this repair but given the situation perhaps I should consider it. I was thinking of say a "C" clip washer pushed onto the shaft behind the gear that could accomplish this. Hey I'm 64. It doesn't have to last a lifetime. Just maybe another 25 years, (if I'm lucky). Lenny

Reply to
captainvideo462002

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You could make a clip like you described out of aluminum, like a soda/ beer can or maybe something thicker if necessary

Reply to
hrhofmann

If you can find the center, where the gear should set, you could use jb weld. I know, it isn't the most professional fix, but it's cheap and works well. My cousin used it to temporarily reattach a spindle on a farm truck. That was two years ago, and still going. Make sure to get the good jb weld, and not the quick set. You should clean the area out with rubbing alcohol before applying the jb, but be tidy with the alcohol, it can goof up old paint, plastics, Bakelite, printing, decals...

-J

Reply to
Sansui Samari

r

I know that JB Weld is great stuff. My son raves about it all the time. Are you suggesting to kind of jam it in between the shaft and the eccenric hole in the gear to take up the space? And if so then how would I keep it from adhering to the shaft? Also the aluminum clip idea sounds like a good one but I think that if I went that route it would have to be a section from the pop top to realize the thickness I need. And wouldn't steel or brass be a better choice though? Lenny.

Reply to
captainvideo462002

Lenny,

I like the idea of the aluminum, as it will be the softest part there, so it will take all of the ware. You might need to replace the shim every few years, but that's not a big deal once you've figured out the shape.

Regards, Tim Schwartz Bristol Electronics

Reply to
Tim Schwartz

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The jb weld would adhere to the shaft. It does come off with a bit heat though. As for the shim idea, I work on a lot of industrial machinery, and aluminum is usually not a very good shim for a moving part. It wears quickly, and is brittle when very thin. I usually use brass. I foresee problems with the shim idea though. I'm pretty sure, you'll have a hard time keeping the gear centered, as well as problems keeping the shim from falling out. It'll probably be tough to keep the gear from slipping as well. Short of risking destroying it to take it apart, I think I'd try the jb weld, or maybe another epoxy, that is easier to remove. If the wheels weren't a brittle cast, a competent machinist would have no problem pressing them out, but in your case, I don't think I'd try it without a spare or two.

Reply to
Sansui Samari

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