Front wheels on 4-8-4 keep derailing

[PatMatDec]

Hello, I have a bachmann 4-8-4 steam locomotive that constantly derails. The front wheel set does not stay on track. If I remove the front wheel set the train works fine. Any suggestions on keeping the front wheels on track?

[K487]

PatMacDec:

When I have that issue with Bachmann steamers what fixes the problem about 90% of the time is I take a drill bit about two or three sizes diameter larger than the hole in the truck (that the screw goes through.)  I ream both ends of the hole with the bit, and do it by hand, so the the hole has a V type of shallow  saucer entrance on both ends.  That usually does the trick - it lets the truck stay on the rails while the loco's front end moves up and down. 

And if need be you can take a drill bit just a little bigger than the truck swivel hole diameter and using a drill, drill out the hole so it's just a little larger.

If there's still a problem check that the wheel axle(s) on the truck slide back and forth easily in the truck, and if needed check the wheels' gauge (if you have the tool for it.)

Often the front trucks (and sometimes the rear loco trucks too) just need a little more verticle flexibility where they are attached to the loco frame.  Had to do that to the first Bachmann Berkshire I bought, and the fix (described in the first paragraph above) worked perfect first time. 

K487

[union pacific 844]

i would just loosen the screw a little i have done that to all 4 of my bachmann 4-8-4s  they run fine cents   of cores these are the newer ones

[Desertdweller]

K487, UP844,

Thanks.  I have a Bachmann N-scale 4-8-4 that has that problem.  I have tried to solve it by fabricating a spring, but met mixed results.  I'll try your ideas.

Les

[rogertra]

i would just loosen the screw a little i have done that to all 4 of my bachmann 4-8-4s  they run fine cents   of cores these are the newer ones

Excellent suggestion.  As for springs over trucks? I remove all mine and do not have a problem.  Removing the spring also puts a little more weight on the drivers as then the trucks just go along for the ride and carry zero weight.

[union pacific 844]

ok i have ho scale not sure on n scale stuff

[Doneldon]

P M D -

If loosening the truck screw doesn't work, check to make sure the wire connecting the loco and
tender isn't exerting some side force. Also, consider adding a little weight inside the tender as
close to the front as you can do it.
                                                        -- D