1662/1663 replacement or O31 friendly wheels.

Answer I found this motor with Baldwin wheels in my spares.  It was left over from make 1 out of 2 project on a 229.  At least that is what my memory tells me.

The baldwin wheel diameter that runs on the rails is approx .08"/2mm bigger.  That means the engine stands .04"/1mm taller.  At first it didn't run well.  The 1662 has sliding shoes and I needed to spread them open some to get good contact again.  I think it looks good and runs well on my O track and switches now.

The 229 had roller pickups that reached a little farther.   

This may help to explain my 1656 that has this style motor, the 1662 style wheel and roller pickups.  It really doesn't like the switches since the roller bottoms out also.   

Edit 8/12/2023:  1656 was made to handle the switches and UCS, no change needed.   The problem I found with my 1656 is explained below.

I would leave them the way they are.  If it all original, and both marker lights are there,  the 1662 & 1663 are worth about $250. each.

@VHubbard are you saying that your stock postwar 1656 doesn't like O31 switches?  That's news to me, because that's what the loco was designed to run on (or the contemporary 1121 O27 switch.)  Please tell us more!

It's known that many prewar locos, like the 229 (and probably your 1662) had single-reduction gear trains, and driving wheels with gear teeth that extended almost to the flange.  I have a 229, and I was planning to upgrade it with the chassis from a 1656 to gain IMPROVED compatibility and more gear reduction.  Please elaborate on your issue before I invest a lot of time in a project that may not work.  Thanks!

I believe the problem is the single reduction wheels have gear teeth that extends below the wheel tread. Most early switches were a style called “swing rail” or something like that. The closure rail pivots and at the end opposite the points, butts up against the stock rails. This results in no gap and no frog.  Without a frog there is no need for a guard rail on the rail opposite the frog. On the 711, 022 and 1122 switches Lionel got rid of the “swing rail” design and went to turnouts with frogs and a guard rail opposite the frog. This is like the turnouts that real railroads use. The guard rail is designed to push the inside of the wheel flange toward the stock rail so the flange on the wheel at the other end of the axle does not hit the point of the frog and derail.

The problem with this design is that the gear teeth on the single reduction gear wheels hit the top of the guard rail causing the locomotive to jump. I have found that Lionel track and train compatibility is only assured on equipment from the same years catalogue.  Finding replacement wheels would just be luck as the gear centers on the wheel and idler gear would have to be compatible.  

It was rare to find the wheels that would work for the 1662 from a 229.  They are the same era and motor design.   

I made an assumption that the 1663 has the same problems as the 1662 with switch and UCS.   The parts lists for the engines shows the wheels and motors are the same.   I can't tell from my 1663 now that I examine it.  My 1663 has a 1656 motor in it. Previous owner already made it switch and UCS friendly.    Not always easy to find an intact engine after 85+ years.   

Update on the 1656 made in 1948.  I have put a new set of pickup rollers on the 1656.  Comparing the old ones, they had been adjusted by a previous owner.  Which may have caused some of the bumping problem with the 1656.  My 1656 is still noisier than the other postwar steamers going through the switch, but it does not jump and bump like the 1662 did.

The 1656 was designed to be more friendly to the switches and UCS track made in 1949.   Compared to the prewar 1662.   The inner width between flanges is 1.06-1.08".  .06-.08"/1.5-2mm wider than the prewar 0-4-0.   The wheel gears are also a smaller diameter by about .2"/5mm.  The flange depth is .04"/1mm less.   

The other difference is the tenders.   The prewar tenders did not have a 3rd rail pickup.  The postwar slope back tender for the 1656 does have a 3rd rail pickup. This makes the 1656 switch friendly with the e-unit enabled.

I don't have a 1665 made in 1946, but I notice it has the larger gear diameter on the wheel.  Anyone know how it handles a UCS track?