Just making nice DCC conversions of a pair of “old-stock” but “new in the box” Stewart U25Bs. They ran fairly well in the pretest, and I thought all was well.
When trying to quiet them down after the conversion, I found that 7 of the 8 axles in the locos had the old split gear problem. [banghead] I thought only P2K had this.
I have many replacement sets of P2K on hand, but they are substantially smaller in diameter than the Stewart wheels.
I have an request in to Bowser website.
In the meantime, does anyone have a line on a manufacturer that could match the Stewart loco wheel sets, or if replacements are available from Bowser? I’m a little nervous that I have just wasted these DCC conversions.
If it’s one of the earlier runs, and the engine has a Athearn drive, then it is prone to the problem. Nothing new to me…all 7 of mine have had axle transplants.
Do you fellows think the Athearn wheels will fit? I will email Athearn now. I just don’t want to order a bunch of wheels that are too small.
I don’t own any straight out Athearn (only Kato, Stewart, Atlas/Kato, Stewart/Kato, and P2Ks)…so I don’t know what an Athearn drive looks like.
I am not sure about early runs, either. But these are quite old models, I believe. The motor had a pickup from the frame and the locos didn’t have any lights! even though they were “brand new on the sprue” kits. Like P2k I imagine these axles just split as they were sitting in the boxes…probably the same undersized holes drilled that plague the P2ks. (Original seller seems to be The Red Caboose in NYC on 4th Street, which I googled just now and see it is still in business since 1946!)
(Didn’t add the decal to change one loco number yet.)
Anyway, the wheels look about 2mm larger than my P2k replacements. I don’t have a micrometer.
I’m a little slow today…duh. Why didn’t I snap the pic like this first? Here is the unconverted loco’s drive.
Just spoke to the guy at the Red Caboose…just for fun. He believes any U25 are late locos and use the wheels still in production through Bowser. I dunnnno…look ancient to me.
Actually, it looks like my P2K brown box BL2s, except the motor on these contact the frame and P2k don’t. No…the P2k also have a soldered cable off the rail pick up.
You could either buy some axle gears from Athearn, spend some money and get the gears and some good NWSL wheelsets, or buy a replacement axle set from Proto/Walthers (They will fit the same as a Athearn)
OOOOhh, my. That was what I was afraid of. The sets from Proto/Walthers are not the same size. The loco would be too low on the track and start snagging something. I already had to put an underset Kadee on the back because the mounting braket was so low. I hope Athearn can tell me exactly what size they have in stock. I can then get a caliper and check mine.
Well, anytime one presses a piece of plastic over a steel rod there is the chance the plastic will split. I didn’t realize Steward used Athearn drives! But I guess I didn’t pay much attention to Stewart before they began using the Kato drives in the F-units in the 80s.
That U25b has the standard Athearn 42" wheels/1/2 axels. You can get replacement gears from Athearn/Horizon, (I think the P2Ks are currently out of stock). The nicklesilver 1/2 axles are available from NWSL and JayBee.
Don’t forget to isolate the motor from the frame when you convert it DCC. I recommend you solder pickup wires to the brass rivets on the truck frames, (the rivets closest to the motor). You could also replace the motor/flywheel with a Mashima (A-Line) for a more complete upgrade.
The later version came with a Kato drive and trucks. The trucks may be available from Bowser, (actually the whole drive line may be available, check Bowser’s website).
Thanks. Actually, the other loco on the photo is completely converted. I never thought about using the rivets, though. But I did wonder about that kind of swivel pickup in place. I don’t have that anywhere else except in an old rubber-band driven Budd car. I guess that it is probably an old Athearn as well.
Well, I think I see more clearly what you were getting at. I didn’t understand that one could just obtain the gears and press them onto the axles without replacing the wheels. Would that work as well as replacing the axle & gear unit as one, like I have always done with Proto 2000s?
The gears are certainly cheap enough, down in the city in the LHS. I didn’t know they made such a thing!
But if the gear is slipping on the axle now, would something I push on be a good as new remedy?
The gear slipping on the wheels is the fact that your gears are split, which essentially means that the gear is cracked in half on one side. This would cause that gear not to be ‘stuck’ onto the wheelset, causing it to slip on it.
The same gears that you use on your P2K or Athearn locomotives will work on these engines (I.E. the Athearn drive is used on the early Stewart engines, as well as aspects from it used on the P2K locomotives).
Ya anytime you see those silver metal ‘tabs’ sliding along each other for electrical pickup, it’s an Athearn. Many folks ‘hard wire’ the connections rather than relying on the metal tabs. When Stewart diesels first came out around 20 years ago they used Athearn drives, later went to Kato. I think now they do their own??
You should be able to get the parts from Athearn, although Stewart might still have some. Many folks fix their Proto axles by buying Athearn ones, so I would assume you could use them to fix Athearn too!! [:)]
Just a thought, I have one or two Stewarts from this time and eventually just bought new powered chassis from Stewart for them - the models you have are still being made by Stewart, same body - and their newer motors / drive trains etc. are a pretty big improvement over the “blue box Athearn” stuff like these engines have.
