4-8-4 NYC Niagara

[trainmaster971]

This is a 4-8-4 NYC Niagara, model #11305, that has developed a noticeable lope and tick when running.  Is this a common problem that developes or is it a sign that it is about to break its drive axel?  If it is typical can it be fixed? Thanks for any info you can provide.

[Jim Banner]

One of the possible causes of this problem is the locomotive wheels slipping out of quarter.  Resetting the wheels is difficult to impossible to do without a quartering jig.  A couple of types of such jigs are shown at the link below:

http://www.nwsl.com/Brochures/444br-v0502.pdf

Another possibility is that the main rods and side rods are starting to cut the crank pins off the wheels.  This is particularly likely to happen if the locomotive has been subject to a lot of quick starts and stops (intention ones or not) or has pulled a lot of heavy loads or if the crank pins have not been lubricated frequently.  The effect is similar to bad quartering in that the wheels are not timed correctly with one another but no amount of adjustment of the quartering will cure the problem.  Replacing the running gear (wheels, axles, rods etc.) as a unit will cure this problem if the running gear is available.  If it is not, the crank pins can be renewed if the equipment and skills are available.

[trainmaster971]

This loco had been in storage for a while.  The lope and tick developed after I oiled and lubed it when it was brought out and put in use again. It typically is at the head end of a 16 car freight train running on a large, 4.1 scale mile main line, layout with the longest grade being 23 feet at 2.5%.

[Daylight4449]

2.5 is a steep grade, 16 freight cars  is a lot, the max grade for an ho loco is usually around 4% (Not counting Geared locos)

[trainmaster971]

A 2.5% grade is no challenge for most HO scale locos.  I have a proto 2-8-4 (16 cars), BLI 2-10-4 (17 cars), BLI Cab Forward (26 cars), IHC 2-10-2 (16 cars) and an IHC 2-8-4 (15 cars) and they all have been operated for 5 or more years on this layout with no problems.  I have had older Bachmann locos that have split their driver with loads less than these . That is why I was wondering if this newer model had the same problem. My freight cars run light at 4.75 oz each instead of the 6 oz suggested by NMRA.

[Yampa Bob]

Look at the crank pins on one side, see if they are all aligned (same rotational angle). One wheel might have slipped a bit.  Check the other side the same way.

I had one wheel slip on a Connie, causing the "lope and click" you speak of.  The click was the plastic side rod flexing. A little twist of the wheel on the axle fixed the problem. I added a drop of CA to secure it.

I only noticed it when I attempted to pull a long string of cars, and only going forward.  Going reverse the tick was quieter.

As for the 2.5% grade, I just did some rough calculations based on your numbers, that grade is probably a "walk in the park" for your Niagara. 

Good luck

[Daylight4449]

my prarie does something simmilar in reverse, could this be the answer...

[trainmaster971]

I checked the drive wheels and am unable to verify alignment as they are very sloppy in the frame.  No bushings. I had a 4-8-4 Daylight that had a slipped driver which I repositioned. It progressed rapidly to a split driver and had to return it to Bachmann.  I am afraid that is what is happening with this loco. I need to clarify the weights I noted for my cars.  They are for my passenger cars.  My freights are 40 footers and are weighted to 3 1/4 ounces instead of the 4 oz recommended by NMRA.

Maybe if the Bach Man is looking in he could give some insight into this lopeing problem. I would hate to relinquish this loco to the service area forever.