Help in re-wheeling a 251

I find that many times Lionel installed very thin shim washers behind the wheels to alleviate this problem. Just install enough washers to get it to clear. Press those geared wheel axles all the way on so the end of the axle is at the end of the axle bore. If the plain wheels do not have a little hub you'll need to add a washer or two on that side too. Exact gauge is not critical, when I am unsure, I take a clean straight section of straight track, and make sure the wheel flanges sit nicely between the rails, so the tires sit on the rails, and there is a little wobble play which helps keep them from getting pinched on curves and riding out. The wheel sets, once installed, should have a very slight amount of play in them just enough to keep them from binding.

Your clearance issue on the geared side may be due to worn axle bearings that are pressed into the motor frame. These are available if yours are excessively worn.

Gandy

Thanks so much for your help.  I'll give this a try tomorrow.  When I see how "loose" the gear trains are I'm probably overthinking this.  Your suggestion regarding gauging of the wheels sounds like a good workeable solution.  Now to find and assortment of thin washers.

Don

Some wheels have "writing" inside the flange that can interfere with the idler gears.  I generally file them off so they won't hang up on the gear.  It is also good to look for any casting flash.  The 671M-23 washer is a good thin shim for the axles; you can stack as many as you need to get the clearance you need (one or two is generally all you need).  For gauging, I like to use a curved track since cocking the wheels at an angle will show if it is tight, especially at rail joints which for some reason seem to be narrower.  On the plain wheel, if it has a hub, I generally have to machine most of the hub off since the gauge tends to be too wide if left as-is.

Well I am learning.  I figured out the raised MEW lettering does in fact interfere with the idler gears but only after I had staked the gears to the wheels.  Rather than remove the gears I ground off the lettering as best I could.  There is still some raised lettering under the teeth of the gears.  I haven't mounted the wheel/axle sets yet so I could still remove the gears, file off the raised lettering and re-stake the gears.  Do you think this is worth it?

Your advice regarding using curved track is excellent and it is these little tips that makes this Forum so worthwhile.

Don

The wheel should have a little ring that the gear sets on at the out edge (it raises it up to the level of the lettering), so I wouldn't bother pulling the gear off.  It won't sit any lower without the lettering.  I usually use an Xacto knife to scrape the lettering off if I forget to file it off. 

Finished putting the wheels on the locomotive and it works great.  Ended up putting a washer between the drivers and the frame on both sides.

Thanks all for your help!

DON