SW-1 Gear/Slippage Problem

Can you post a clear video with a close-up of what is happening?

The excess side-to-side play affecting mesh of the spur gears is a known problem, and it sounds like you've addressed that.

If you can see the drive wheels spinning and the loco still isn't moving, either all of the wheels aren't making contact with the railhead, or something is snagging the track (pickup roller, coupler, pilot steps, etc.) which stops the loco from moving.  It's very unusual that this problem would rear its head all of a sudden in a loco that worked fine the last time you used it.

Are ALL EIGHT wheels spinning?  Or only one truck?  (I believe there is a lower driveshaft that goes from the fuel tank to each truck.)  Check for debris like ballast, rubber tire, ornamental brake shoe, etc., jammed in the gears, or between the wheels and the truck block.  Let us know what you find.

Thanks for your suggestions. I checked and all the wheels are making contact and there doesn't seem to be any obstruction or blockage. What's interesting, though, is at very low speed (step 1 or 2), the engine will creep along but will - every few seconds - very briefly speed up, the wheels slip, and then the engine reverts back to the lower speed. It does this while moving forward. When I put it into reverse, the wheels spin, the engine remains stationary, and then the engine shuts down. I took the clips out to see if maybe they were binding, but that wasn't the problem.

I have been wanting to post a video, but never learned how. This is a good reason to learn how. But it will probably take me a day or two.

More later.

Jim

The actual product number would be useful here.  The one from 2022 states it has two motors, not the single motor and driveshaft.  However, I still believe these are the single motored design.

Southern Pacific LEGACY SW1 #1000 SKU: 2233420

Without knowing exactly what you have, it's pretty hard to offer useful suggestions.

I have a SW1200 with the same drive. Mine had no grease when I got it but no issues with slippage.

Besides greasing the gears, I had to oil the universals on the shafts too.

FWIW the gear drives in these engines are noisy. Reminds me of the old pullmor growl.

Thanks everyone. The engine is a Milwaukee Road SW-1, #1634 and the SKU is 2233971. It has a single motor and is a custom run for Mr. Muffin. It was released in December 2022 so, if i worse comes to worst, I can probably send it in for repair.

@RSJB18 posted:

I have a SW1200 with the same drive. Mine had no grease when I got it but no issues with slippage.

Besides greasing the gears, I had to oil the universals on the shafts too.

FWIW the gear drives in these engines are noisy. Reminds me of the old pullmor growl.

I haven’t seen one of these yet come across my plate, …..and from the looks of that overly complex, what in the world were they thinking design, …..I’m glad I haven’t!…

😳

Pat

@harmonyards posted:

I haven’t seen one of these yet come across my plate, …..and from the looks of that overly complex, what in the world were they thinking design, …..I’m glad I haven’t!…

😳

Pat

Only a matter of time Pat. 🤣🤣

Agreed, I pulled the shell off fully expecting to find a pair of vertical can motors. SURPRISE!!

I had quite the fun lining up the universal and the shaft to reassemble the trucks too.

Bob

Hows your trackwork? Im looking at the truck mount in the picture above and it looks like its only a swivel (no rocking motion possible). If thats the case, then any dips and bumps in the track are going to lift a wheel, and then its going to spin.

Also, check that the pickup roller arms arent bent and theres not so much pressure on the rollers that they're lifting the trucks.

It could also be that the rollers are bottomed out without enough room to move, and that is picking up a wheel, but I cant imagine that.

The drive is not really all that complex. Its a fairly typical horizontal drive that was used for decades.  Its very similar to the drive in the Atlas switchers, except Atlas put all the gears inside the trucks. The alternative would be to use a differential on each axle, like a Weaver or 3rd rail drive.  I dont really see an issue with what they did its been around for years, save for the external idler gears.  If you want it to creep along, then this is the way.

Are the wheels spinning on one truck and not the other?  If so, check if one of the U-joints is loose on its shaft.  

Bob

As a point of continuing education, there are no dashes in EMD model numbers. Regardless of how Lionel may name it, the locomotive under discussion here is an SW1, not an SW-1.

___________

Here endeth the lesson….

The saga continues ...

How do you remove the motor housing?

Here's why I am asking. In preparation for making a video (still a work in progress), I took the side frames off to expose the gears and the drive shaft. While doing a slow speed practice run, I took RRDOCs advice and made sure that both drive shafts were turning. They worked (somewhat) going forward. When I put it in reverse, the rear drive shaft did not move and neither did the trucks. I removed the rear truck, checked the worm gear again and it seemed okay. I turned the drive shaft by hand, and it seemed rather stiff coming off the motor. My hunch now is that something is binding inside the motor housing. Does it even come off?

Also, as RSJB18 mentioned, when reassembling the engine, lining up the universal and the shaft is not for the faint of heart ... or at least not for those who lack a colorful vocabulary. Rich, thanks for the correction on the nomenclature. I'm grateful, too, to all who are helping with this project.

Jim

@Jim Brenner posted:

The saga continues ...

How do you remove the motor housing?

Here's why I am asking. In preparation for making a video (still a work in progress), I took the side frames off to expose the gears and the drive shaft. While doing a slow speed practice run, I took RRDOCs advice and made sure that both drive shafts were turning. They worked (somewhat) going forward. When I put it in reverse, the rear drive shaft did not move and neither did the trucks. I removed the rear truck, checked the worm gear again and it seemed okay. I turned the drive shaft by hand, and it seemed rather stiff coming off the motor. My hunch now is that something is binding inside the motor housing. Does it even come off?

Also, as RSJB18 mentioned, when reassembling the engine, lining up the universal and the shaft is not for the faint of heart ... or at least not for those who lack a colorful vocabulary. Rich, thanks for the correction on the nomenclature. I'm grateful, too, to all who are helping with this project.

Jim

Jim- When I opened mine, I didn't look too closely but I think the boards have to be removed to access the motor.

I found the parts diagram for mine. Not exactly clear how to access the motor beyond my previous statement. It does show that the motor comes with the Universals attached.

My guess- since they show the 2 screws #36 right below the tank, I'd say they hold the tank to the frame.

Thanks. This is very helpful. The black cap on the left side of Part #10 seems to be the culprit. It has about 3/16 of an inch back and forth movement that, I think, is affecting the shaft's movement. It appears to be a press fit and, if not in the right position, doesn't engage the drive shaft. At least that's what it looks like. Unfortunately, to get at it requires removing the boards and I'm very reluctant to do that.

I'm not certain what my next step will be, but there's a strong possibility that warranty work will be involved.

Thanks again. And a tip o' the hat.

Jim

@Jim Brenner posted:

Thanks. This is very helpful. The black cap on the left side of Part #10 seems to be the culprit. It has about 3/16 of an inch back and forth movement that, I think, is affecting the shaft's movement. It appears to be a press fit and, if not in the right position, doesn't engage the drive shaft. At least that's what it looks like. Unfortunately, to get at it requires removing the boards and I'm very reluctant to do that.

I'm not certain what my next step will be, but there's a strong possibility that warranty work will be involved.

Thanks again. And a tip o' the hat.

Jim

Happy to help. If it's still under warranty then call to Lionel might be in order.

@Jim Brenner posted:

Thanks everyone. The engine is a Milwaukee Road SW-1, #1634 and the SKU is 2233971. It has a single motor and is a custom run for Mr. Muffin. It was released in December 2022 so, if i worse comes to worst, I can probably send it in for repair.

A no brainer, send it back for warranty repair!  I'm not sure why we're even having this conversation!

Well, we're having this conversation because we're trying to do the simple things first.

That "black cap" includes a slotted plastic wheel that tells the speed control circuitry how fast the motor is turning.  On the parts diagram that I found, it's not sold separately, only as part of the motor assembly, for $42.  Supposedly, taking your train apart voids the warranty.  So if you go the warranty repair route, try your best to put everything back together as it was from the factory.  If you want to try repairing it yourself, you could buy a new motor assembly and keep the original. Once out of the loco, you could probably figure out a way to put the cap on tight.  It might not hurt to have a spare motor on hand.  My $.02.

As an update, the engine is running, and the beer is flowing. I sent the engine to Lionel on 27 November and got it back yesterday. Their note said that they'd switched out the chassis which tells me that the problem was something that couldn't have been fixed at home.

@Jim Brenner posted:

Well, we're having this conversation because we're trying to do the simple things first.

John is correct send it back, the reason he takes that stances if you screw something up trying to fix it that will be the end of Lionel fixing it. Box it up send it back