Front truck jumping switch

Is the derailing happening at the frog or the points?  If at the frog, there's a chance that while the pilot truck is naturally pulled to the right in a curve, the flange of the right wheel gravitates towards the through path in the frog.  At the same time the left wheel hops the lead end of the diverging guard rail.  It appears the pin at the lead end of the guard rail is relatively straight compared to the others.  Bend the pin on the diverging guard rail inboard to match the angle on the other guard rail pins and see if that helps guide the truck through.

After some comparing, it would appear the guard rails on GG turnouts could do with a bit of lengthening.  But then I'm new to GG...i just began passing trains over them last weekend.

Bruce

Precisely measure the gauge of the switch, and compare the gauge at the frog with that a few inches away on on a track section.  I had one Gargraves 100 (out of several dozen with no problem) that narrowed very slightly at that point, and the single axle leading truck on a steamer was slightly wide, forcing the wheel flange to go the wrong way at the frog.  Track was about 2-3 mm narrower at that point/.  Moved the outer curved rail slightly to widen the gauge.

It is really worthwhile to have the NMRA gauge for the measurements.

There was a two wheel pilot truck on the first batch of Lionel scale Consolidations with Vanderbilt tenders. These trucks were derailing on switches constantly. Lionel send out a spring to put more downward pressure on the truck, but that didn't seem to help.

Turns out that the wheels were gauged too narrow. Bringing the wheels into gauge by spreading them, eliminated all of the derailments.

It's easy enough to check using a piece of track as a gauge.

That pilot truck looks seriously messed up. There is a wrong axle retainer on the left hand side. Looks way too long and against the wheel. The wheel set should be centered in the truck frame. There should be some horizontal slop so the wheel set can move from side to side. And the wheel should be centered on the knurl on the axle. The way it is now the gauge is too wide. I can see why you are having derailment problems!

Are they the plastic snap in bearings/retainers?  Good eye, Chuck!

is this your engine?  The short bearing is a trailing truck bearing.

I hope you need some other stuff from Lionel or Chuck has some.

The problem is with the center point when switched for turnout. If you zoom in on the picture you can see the gap that the front truck will cause the switch to open. Take needle nose pliers and bend the tip out a little to close the gap and it will work fine. The flanges on the wheels of steam engines pilot trucks come to a sharper edge sometimes causing the switch to open just for the truck.

Picture shows problem area.

First off, where would I get an NMRH gauge for O scale? Secondly, since that will take time, what measurements should I check for with a good set of calipers? Chuck, I have uploaded some additional pics of the truck and axle. I can't "see" what you mean by the wrong sized retainer?? Yes it is my locomotive. I bought it as part of a Lionel ready to run set a few years ago but it hasn't seen much running time till lately.

looks like they are here  NMRA

From the Lionel Parts link that I provided... Pilot is front which is wrong on yours?

QS 904  Do you think it's the front truck or the switch points splitting open?  Is there any way you could hold the points in position and run the engine over the switch , Maybe you have a helper that could hold the throw bar in position? ...   Is it just this one switch or all of them?

Moonman,

I tool all 6 plastic bearings out. The front 2 measure .188" total thickness and the trailing truck 4 measure .183" total thickness. They all look more like the -051 piece. Of course I do not know what actual thickness either part is supposed to be. What do you think?

Perhaps it was the angle of the photo that made one in the front look different. No, I do not know the specs.

Is one of the fronts cracked on the side opposite the rail?

While you have the wheelset out measure the inside flange to flange. There is some knurled area of the axle showing and it shouldn't be. Check the measurement against the drivers and trailing pilot wheels. Too narrow would cause derailment.

Tap the wheel so it covers the exposed knurl and that should get the wheelset in gauge. The angle of your first photos made it look like there were two different axle retainers.

Just take the front truck by itself and run it slowly through the switch and closely observe what it does. You should be able to determine what adjustments, if any, the wheel gauge needs to be.