I finally got around to pulling the flywheel off, and it is indeed 1/8" (0.125" / ~3mm)…Now I don’t know where I will get my flywheels. Could someone with the latest Walthers catalog tell me if they list the dimensions for the Timewell Precision part #1033 in the catalog? I’m living out of last year’s edition (Timewell not represented), and they don’t list the info online. All of the other flywheels with 3mm shafts I can find in the old edition are too long or too wide. I guess I could get one with the appropriate external dimensions, and a smaller shaft diameter and try to drill it out to 3mm, but the less work the better!
The dimensions that I came up with for the current flywheels are shaft- 3mm (1/8"), OD - tapered 18mm - 20mm (11/16" - 3/4"), L - 8mm (5/16"). The OD is going to be critical as well. The shell tapers towards the cab, and a 20mm will probably rub the shell at the narrowest point, so an 18 mm OD is probably more correct.
Apparently Timewell doesn’t have a website either. Doesn’t seem to be much other than the description at Walther’s that says “fits Athearn S12 - SW1500”.
I have one Protopower 20013 flywheel laying on my workbench. Also have one STOCK Athearn, which oddly enough I haven’t thrown out yet. The stock one is 0.735" at the big end and tapers down to 0.700". It is 0.310" thick. The Proto one is 0.680" at the big end and tapers down to 0.630". So, overall it is slighly smaller than the original. The thickness is 0.375", so it is slightly thicker (longer 0.065") than the Athearn. Since the Proto is 0.070" SMALLER at the small end, I don’t think the little extra length will hit anything. This is the same flywheel that I have in one of mine, but it’s on a can motor.
I guess if I were doing it and not going with a new motor, I’d get the 2.4mm hole and just ream it to 0.125" BY HAND with a 1/8" drill.
One thing you’ll notice, the old Athearn flywheels did not actually attach to the motor shaft. The plastic coupling went through the flywheel and the coupling was actually on the shaft. The new flywheels are nearly a press fit to the shaft (usually cemented on with loctite of some type) and then the coupling just presses on and fits in the recess in the flywheel.
After searching and search and searching the 'net I finally found a link to the info. The info is actually on the Walther’s site, but not linked to from the item search results for some reason. Here it is (for posterity) http://www.walthers.com/exec/productinfo/712-1033
It would appear that this is the way to go. The flywheels are sold singlely per the Walthers rep that I contacted.
Just an update for any one who cares (and/or posterity). I finally got a multimeter that will measure up to 10A. I measure the stall current at just below an amp (.90-.95A), she runs around with an average (unburdened) draw in the .3 -.4A range. Everything looks to be a “go” for the DZ123.
I’m still waiting on the new flywheels. I installed the new motor pads, and that made a huge difference…I wouldn’t say it runs quiet now, but it also doesn’t sound like a jackhammer circling my layout!
I hope to install the decoder and lights this weekend. Thanks again to all who offered guidance.
One last thing you can try to quiet it even more is get some CRC 2-26. It’s an electrical contact cleaner/lube. You can get it at Home Depot, I had a hard time finding it, but if you ask they do have it. Do a search on these forums, some folks seem to think it works wonders help quiet Athearn motors. It sure doesn’t hurt. Just put a touch on the com after you are done cleaning it.
FWIW, I’ve used the 2-26 on other stuff around the house and it seems better than many of the spray cleaner/lubes you buy.