Bachmann Model 660 Santa Fe 4-8-4 Steam

[Unclewoody62]

Sub: Drive Wheel

Hello,

Rather new to this hobby and wouldn't dare take apart a nice steam locomotive. I bought this unit used. It looked well kept, in the original box, and I really like its design. So far, I've only wipes the wheels with alcohol wipes, and very lightly lubed the exterior points. When on the track, the engine sounds strong but hardly moves without some nudges. When it does begin to move...the drivewheel just pulls away from the chassis until it pulls completely off the chassis. I reinsert it...though it just doesn't stay put.

What is going on here?

Kindly,
Uncle Woody

Chesapeake Va

[Trainman203]

An important model railroad lesson, always learned the "hard" way, myself included....

"Beware " of "used locomotives " bought sight unseen or without benefit of a test run.  Especially with discontinued models such as this.  To get parts, you may need to buy another one to cannibalize for parts.  I had to do this once before I learned.

[Trainman203]

If the engine has difficulty in moving and then a driver is forced down,  there is a bind in the mechanism somewhere.  A steam engine has many places this can happen. 

I'd start by seeing if the crosshead guides at the cylinders are bent inward , causing a snag on the rods behind it.  These can get easily bent by mishandling and not be very apparent visually.  You have to look from under the engine to really see.

Another possibility is congealed and solidified lubricant on the main gear/worm gear inside, although you have to take the engine partially apart to see and correct.

I've had both those problems.  Check them out first and report back.

[Unclewoody62]

Thank you for promptly replying and for sharing your experiences and knowledge. It may take me a couple days before attempting the repairs you've suggested. I will report back with my findings...

God Bless

[Len]

"When it does begin to move...the drivewheel just pulls away from the chassis until it pulls completely off the chassis. I reinsert it...though it just doesn't stay put."

That sounds like you may have a split gear that isn't holding the axle properly. That would let it get out of quarter and bind up, creating the pressure that forces it out of the chassis. When you open the loco up, check the drive gear on the axle for any cracks or splits.

Len

[Unclewoody62]

Thank you Len for responding. I will look for this too. Good info..

God Bless

[Trainman203]

Uncle Woody, you probably are going to have to partially disassemble and remove the boiler shell to see the mechanism.  I looked for an exploded drawing but couldn't find one since your engine is an old discontinued one.  Maybe some one knows where one could be had.

When you disassemble, it's a good idea to put each screw into a small enclosed container like a prescription bottle, I'm here to tell you that there is nothing quite like losing one of those screws.  Or you can, after separating the parts, put the screw back in the hole it came from.  Whatever you do, don't leave them just laying loose anywhere.  Especially with this being a discontinued model.

If you really like this engine, start mentally accepting that you might have to buy a second one to get a part.

[Unclewoody62]

So noted...  several great tips!! Thank you