# Help needed quartering the Accucraft GS4



## zr1rob (May 27, 2020)

When I push the loco, the drivers will turn about 1/2 circle, but then really get hard to move. I remember when I first got it, it was easy to push by hand with no drag at all. I replaced the 2 and 3 drivers with flangeless wheels to help on tighter curves. But I must have done something wrong when reassembling the loco. The drivers seem to be quartered, the best I could do without a jig. The counterweights on both sides are aligned with each other and are 90deg out of phase with the other side. Any help is appreciated. Thanks, Rob


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## ferroequinologist (May 8, 2016)

Could be timing of valve gear if you think the quartering of the wheels is good ? Or maybe some parts of the valve gear now hitting another part this can often happen when it gets bent during disasembly/ re-assembly of the parts so check for any striking of parts or maybe incorrect assembly of side rods like one fractionally longer in the wrong spot. It's hard to help without being there so anyone else close by you know has one the same to compare?
Russell


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## David Leech (Dec 9, 2008)

Are we talking electric, or live steam?
Are the two axles you replaced, reversible?
Quartered doesn't necessarily mean exactly 90º, so maybe the first and fourth aren't exactly the same as the new 2 and 3!
Can you try with the original axles back in to verify that they still work okay?
Cheers,
David Leech, Delta, Canada


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## zr1rob (May 27, 2020)

Thanks for the answers guys. It's electric. I'lm going to work on it this weekend and try your suggestions and report back about it next week. Rob


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## Greg Elmassian (Jan 3, 2008)

Roll it until you get resistance, then wiggle the side rods and find which are binding... maybe it's something else, but this is the first check.

Greg


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## zr1rob (May 27, 2020)

When I disconnected the motor shaft from the driveshaft to the gearbox, so the motor could run free and the drivers spin free, the drivers turned perfectly, with no extra effort like when the motor was connected. However, when I run the motor, it will try to spin but stalls immediately. The motor is either damaged or misaligned. So the motor needs to come out.

Can someone tell me how to remove the motor? It's right above the trailing truck, ahead of the cab. I'd really appreciate the help. Thanks, Rob


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## zr1rob (May 27, 2020)

O boy, the problem is FIXED. Turns out the motor wasnt siezed, the drivers were quartered. Everything is fine now. What happened was the motor was having trouble getting moving as it is a gear motor and the grease in the gears had somewhat solidified over the past 20+ years. This loco was a shelf queen most of its existence, till I bought it a couple of years ago. So it never ran much if at all. I stuck a RailPro receiver and battery in the tender and it always ran slowly. Also, the undercarriage is too stiff and any track anomaly will derail it. So I disconnected the driveshaft, applied 24V (more than RailPro will allow) and the motor shaft started turning, ever so slowly at first, but after a couple of tries, in both directions, it started running smoothly. I reconnected the driveshaft and now it really runs great. BTW: the front and rear drivers run on sintered bearings with 3 very stiff springs for suspension. I removed the center springs from the front and rear drivers. I'm going to run it later this week to see if that helps. If it does, I'll write up a little post describing the things done to make this shelf queen a nice runner.


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## Greg Elmassian (Jan 3, 2008)

I'd strongly consider opening the gearboxes and replacing the grease.... if it has solidified over the years, it's lubricating qualities are at the very least questionable.

You may have broken it free, but it's very likely the grease is not doing it's job. I gather this is a Pittman gearhead motor?

I know you don't want to take it apart, but I think there is real danger of running it and getting abnormal wear.

Greg


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## zr1rob (May 27, 2020)

Greg - Getting the motor out of the shell is a big problem - there aren't any assembly instructions on the net, I'm looking for someone with the experience of opening this unit up and getting the motor out. I don't want to take a chance with it at this point in time unless there's a clear step by step method to get at the motor. I agree that it's probably true that the lube in the gearbox is suspect and should be replaced, but there's no way to get at the box without the motor, which means the motor has to come out first.


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## Greg Elmassian (Jan 3, 2008)

I have a couple of the K4 Pacific locos, and taking them apart can be tricky. If you keep looking, perhaps you can find a step by step to pull the cab and boiler.

I would recommend getting a set of WiHa drivers, inexpensive drivers will ruin screw and allen heads.

i wrote up my disassembly procedure on my site, pretty typical of Accucraft locos:





K4 Disassembly


Greg Elmassian web site on large scale trains and garden railroads, cigars, and computers




elmassian.com





Greg


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## Pete Thornton (Jan 2, 2008)

zr1rob said:


> the front and rear drivers run on sintered bearings with 3 very stiff springs for suspension.


Just a thought about your drivers and derailments. I had an RYM EBT Mikado which had very stiff springs. We initially reduced the springs on the outer drivers but I thought afterwards we should have dealt with the center pair of blind drivers (actually makes no difference whether they are blind or flanged.) If the center drivers are stiff, and you get to a hump, then the loco will rock on the center drivers and possible derail.

What you want, for perfect tracking, is for the motor and driven axle to be relatively firm, the front axle should be allowed to rock about the longitudinal axis (so give it lots of up/down play on each side but don't make the springs too soft,) and the center wheels should be lightly spring so they stay on the rail head but move up or down when the two end axles are on rough track.


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## zr1rob (May 27, 2020)

Pete Thornton said:


> Just a thought about your drivers and derailments. I had an RYM EBT Mikado which had very stiff springs. We initially reduced the springs on the outer drivers but I thought afterwards we should have dealt with the center pair of blind drivers (actually makes no difference whether they are blind or flanged.) If the center drivers are stiff, and you get to a hump, then the loco will rock on the center drivers and possible derail.
> 
> What you want, for perfect tracking, is for the motor and driven axle to be relatively firm, the front axle should be allowed to rock about the longitudinal axis (so give it lots of up/down play on each side but don't make the springs too soft,) and the center wheels should be lightly spring so they stay on the rail head but move up or down when the two end axles are on rough track.


Pete -
I think you're right about loosening up the center driver spring suspension. I ran the GS4 today, and it tracked better than ever, and smoother than ever since the gearbox run in, see above. Anyway, it still derailed in a few spots where the curves got kinked due to the sun (which have since been fixed) I'll cover that in another post.

Anyway, Aristo SD45's as delivered are very finicky (at least mine were). So I disassembled the motor bricks and removed the motors and gear boxes. In there are placed a couple of semi - stiff pieces of rubber under the outer axle gearboxes. They are supposed to be there to allow those axles to swivel side to side, but they get hard as they age and make tracking real stiff so they derail the loco. Just like the GS4, I put some new springy material of the same thickness under the center axle, and now the locos track great.


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## benshell (Oct 1, 2008)

Hi Rob, I'm barely ever on here anymore but glanced through the email digest and saw this... I'm having what is likely the exact same problem. I bought a shelf queen that barely runs. I'll have to try your solution! I do really want to figure out how the open the locomotive up though. I want to install DCC/sound, and would like individual control over the all lights, and I might add a speaker in the smokebox too if there's room. Keep me posted if you figure out how to open it up; I'll do the same.


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