Kato Mikado

[carmelmodelrr]

One of my Kato Mikados (DC) is an old one--I believe it was the first that didn't need to be assembled by the purchaser.  When I placed it on my layout I was surprised that it ran hesitatingly.  It runs, the light blinks and the loco slows, then all is well for a foot or two when the whole thing is repeated.  I've cleaned every bit of the tender's wheels, including the cups, but there is no improvement.  The drive wheels of the loco are all clean and the traction tires are good.  What is my next step?

Thank you in advance.

carmelmodelrr

[nickelplate759]

The first run of Kato Mikado's (circa 1996) had driver contact issues - so much so that Kato sold replacement drivers.
There's more information here: https://www.therailwire.net/forum/index.php?topic=36114.msg427105#msg427105

[mmagliaro]

I doubt it is the problem with the early drivers.  Those were a problem, but when the tender wheels and cups are clean, and the drawbar wires are making good contact all the way through to the engine post, it should run really well most of the time, with a possible little pickup hiccup over a turnout.
Do I understand you correctly, that the headlight flickers just before it slows down, and then it runs slow, and then speeds back up and runs normally?  If that's what you meant to describe, this sounds like a partial short somewhere.

Things I would check...
1. Unhook the tender, flip it on its back in a cradle and touch leads to the two frame halves.  See if it runs normally, or if the
problem is present.  If it still had problems, then the issue has nothing to do with pickups.

2. Check that there is good separation between the two frame halves - especially at the rear and front.  If seen some where
the frames bend inward at the bottom so closely that they short out to each other.   They might be REALLY close and intermittently touching as it runs.

3. If the frames look okay, and you see this problem on its back, pull the shell, remove the motor and check that with leads

After you check these things, keep writing back and we'll keep narrowing it down.

[Jimbo]

Check to make sure the drawbar isn’t broken.  I had two of the first run, and one of the two had a drawbar that had broken during shipment (subsequent runs had new packaging to reduce this problem; specifically, a white piece across the bottom to hold the model rigidly in place.)

The one with the broken drawbar had problems similar to what you described.

Jim

[carmelmodelrr]

I removed the truck that holds the drawbar to the tender, then applied power to the drawbar.  Loco ran just fine.  It seemed that one wire of the drawbar was less than circular so I bent it into the best circle that I could.  The loco runs better--not perfect, but better.   I have a bunch of Mikado (and other) Kato parts, but no replacement drawbars--and Kato is out of stock.  So I'll see if I can live with what I have (for now, anyway).

Thank you for your suggestions and comments.

carmelmodelrr

[nkalanaga]

Is it practical to hardwire around the drawbar?  As many hoses as there were between steam locos and tenders a pair of wires wouldn't look out of place.

[mmagliaro]

Now that it improved, have you tried touching leads to the various driver pairs?  If it is an old run and some of them are dead (or all of them), that would account for some occasional stalling.