Noisy Kato NW2

I just got a Kato NW2 and was doing a run in before adding a decoder. It is very noisy. i checked it out and can't find any obvious causes. It ran fine on DC and runs well with the decoder, but it is very noisy. It almost sounds like a grinding noise, but there does not seem to be any binding. I can't figure what is going. Most of my Kato locos are so quiet, you hardly know they are running. This thing is almost as bad as my Z scale MTL F7's. Any ideas or experience?

Trey

 

Yeah, these are a bit noisier than your typical Kato I believe due to an increased number of gears used in this model (although I never really experienced grinding, just more general running noise). If you're not experiencing binding, perhaps just let it break-in for a while as it should probably quiet down some more.

 

It runs pretty well, just noisy. I read some other posts saying the same thing. I can live with it. Thanks.

Trey

 

The drive train in the Kato NW2 is kind of unique. The motor feeds a pinion to a two-gear spur gear reduction that transfers the centerline of the drivetrain under the motor. From there, there are two smallish universals to short driveshafts that each go to another universal on the trucks.

The whole works is clipped together with the motor carrier. But it is pretty well engineered. You can take the trucks and lower driveshafts off of it pretty easily to make sure those aren't causing a problem - just hotwire to the frame halves and see if the racket persists after the trucks are removed. The design of this is pretty good - you can disassemble and reassemble it without wondering if you'll ever get it right again. Unlike an old Atlas Classic GP that could howl like a banshee if the motor/universals got even slightly out of line, they are pretty consistent to fit back together the way they came apart.

If it does make noise with the trucks off, it's probably an alignment problem between the motor pinion and the spur gear reduction tower. The gear tower clips on the motor, so you can remove those and examine it separately looking for issues. I'd guess you've got one gear in that set too loose or too tight on the shaft and a little tweak will fix it. They are by nature a bit noisier than some, but mine is pretty darn quiet and so are the raft of them I turned into SW1's.

You also want to look at the flywheel and make sure that isn't rubbing against something in the back of the frame.

Here's a really good shot of how this thing is laid out inside:
http://www.trainboard.com/highball/index.php?media/kato-nw2-chassis.119200/

When I used to make SW1's out of these I field-stripped every one down to frame halves to grind the frames down, then reassembled them, and every one as just as good put back together as they originally were. I wouldn't be afraid of it. The only 'be careful' on those is the little metal clips from the top electrical board to the brush holders, those want to be removed carefully with tweezers and they want to fly. I probably tore down about 30 of them, and I still have two of my own. I know some people have had issues with both noise and cracked gears, but mine have been really pretty good.

I'm kind of doubting that 'running it in' will really fix the noise, I'm thinking you've got an assembly problem in there somewhere.

 

Thanks for the info. I am gonna take it apart again and check the gear alignment. It is kinda like the transfer case on my jeep. It runs very well and even creeps along steadily. I am using it for an Inglenook switching layout, so the noise won't be such a huge deal since it won't be flying around at warp factor 9. I just wanted to make sure there was not something I was missing. Thanks everyone for the help.

Happy Holidays All
Trey

 

What solutions do you have for Atlas GPs, beside the Beardon solution?

 

Honestly? I've messed around a lot with them, and came to the conclusion that with the 'Classic' GP's with the hex nut in the flywheel, you either get a quiet one or you don't, and if you don't you can 'maybe' mess around with the position of the hex nut on the worm gear shaft, the motor alignment horizontally in the motor carrier, etc., to try to reduce the racket.

Bluntly, I have two that are so noisy I gave up on them. When I got a new-production GP, I was rather stunned on how quiet it was and examined it to discover they came up with an entirely different short universal that doesn't make racket. I was so impressed I got a second one and have decided that if the noise bothers me enough, I'll buy a new one and sell the old one (with sufficient warnings) on Ebay. Since the mechanisms are entirely swappable, this solves the problem of the fast motor and the racket at the same time.

 

Until Hornby came out with their SW1's, I was doing custom builds using my resin bodies of SW1's based on the Kato NW2. It took some serious frame grinding to get it to fit, but it was repeatable, and would reassemble and run just fine. At this point I'm not sure anybody really cares about doing SW1's out of these as the Hornby ones are really pretty good. There was no way I could put out my converted SW1 and match that price, and from what I've seen, performance was equivalent, so I pretty much folded my tent on this one.





PM me or email me if you want photos of the frame grinding process - I just used a dremel with an abrasive disk and some heavy leather gloves as the frame gets really, really hot doing this. I 'might' have one resin shell left.

 

Randy's SW-1 out pulls the Hornby SW-1. I don't know why...

My Hornby engines pull about 12 cars, Randy's will pull about 15.

They also run well together.

Randy

 

I had a similar situation. I had an ATSF Life-Like SW8 that I really liked, had weathered and detailed, but like every LL I've ever owned, if it sat around for a while the wheeltreads would oxidize and it would repeatedly stall until it polished them back up from use. I can deal with that on road units in MU consists, but a stand-alone switcher creeping through the yard was a PITA. I got a Kato NW2, and like every Kato, the wheel metallurgy is different, grips better, and doesn't oxidize much at all. So I transplanted the NW2 mech into the SW8 body and its still running just wonderfully. I just ran it around this last weekend after it had sat for several months, and it never hiccupped at all. About the only thing I really am looking at is putting tiny LED's in for the headlights instead of light pipes.

Changing over to NWSL wheels might fix this as well, but if you've ever wondered.... yes, you really can transplant a Kato mech to a LL body.

 

NW-2s has a minor design flaw. I've spent a lot of time with this loco and have written an article for N-Scale Mag. Maybe one day they will publish it.

This photo is actually mine. It partially shows you the problem.





1. The real problem- slipping gears on shafts. I found that both of those white gears may slip when under load. The gear on the motor can be a challenge to get to. You have to pull the flywheel off. And then if you use some sort of adhesive, you don't want to get it in the motor bearing which is so close on one side.

Kato needs to redesign this in my opinion. Maybe put some pinches in the shaft so they have "little teeth" that bite into the gear.

2. Noise. Noise is cause by the drive shaft slipping and MOVING to one side or the other.
In fact, if you study the photo above you can see the problem.
Look at the shaft with two black cups on either end.
Look at the spots of silver shaft peeking through all that stuff. Notice anything?

The entire shaft is shifted to the right.

This could possibly place a bind on the front truck-- thus leading to excess noise.

I found that when I gently experimented with shifting that shaft so that it was centered that the loco quieted down.

And by the way, just handling the loco can shift the position of that shaft.
Just try it. Hold the loco and mess with the trucks. You will find that you can force that shaft to the front or back.

So when you get it in the best position.... handle the loco carefully so as not to move the shaft out of place again.



Kato came up with a unique design for this little switcher I commend them.

If they could just make those gears bite the shafts better, the loco would be perfected.


Here is what I did with my NW-2. I kitbashed it to a late phase for CSX.

 

Great picture. That gear alignment is exactly where thought the noise was coming from. Thanks for the info. I will have to give a try.

Trey

 

Thanks for the photo and information Ron. This is great!

I've got an NW2 that I custom painted and really like. Pickup and slow speed are flawless but I could never get past the noise so my modified LL SW9 which runs perfectly always got the nod.
I'm going to revisit the NW2 and see about quieting it down.

Jim

 

I revisited the noise issue in my NW-2 and discovered it was not the driveshaft gear, but the cab interior and lighting insert that is rattling. I removed the shell and adjusted the drive shaft and ran without the shell and it was much improved. I replaced the shell and it was as loud as before. I tried it again without the shell and quiet again. Then I realized it was the interior insert. I tried it with the shell and no insert and much improved. I will try some kapton tape and see it I can get rid of the noise.

To be continued.

Trey

 

Still not Kato quiet, but a lot better. It's going to be switching an Inglenook, so I think it's a win.

Trey

 

I just recently got one of these for a small shunting layout I'm building and it turned out to be quite noisy too. Upon disassembly, I found I could wiggle the rear motor shaft (the side without the flywheel) side to side quite a bit, like the center hole in the bearing is too big. It would also make a ticking noise when spun by hand too, and when run by itself with no gearing attached, it sounds like a bloody moped (I had a bit of fun revving it up, lol). Anyways, I called Kato about it, but they seemed to think it was just another complaint about the gear noise these things make. I'm guessing from what I've read online that they probably get it a lot, lol so it's understandable, but I'm pretty sure there's something genuinely wrong with mine. I tried adding some Labelle 102 to the suspect bearing hoping to give the shaft a bit of a buffer to fill the excess space, and it did get rid of the free spinning ticking and the running moped noise, but it still doesn't sound quite right in the back end of it, so I just went ahead and ordered a new motor. Hopefully it does the trick!

Thankfully the white gears on mine seem pretty solid on their shafts, but I suppose I shouldn't jinx myself, lol