Kato WP F3A loco not moving until 40% throttle. All my others move at 20%

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#1
So I have a new Kato WP F3A loco that Ive been running along with my other new engines. My powerpack is an MRC1370. I've noticed that this engine doesn't want to run until Im at 40% on the throttle and then its rolling a t a decent clip. My other engines will start moving smoothly at 20% throttle but they are 6 axle units compared to the 4 on the F3A. I remember seeing a thread about a similar issue with another member's engines but I cant find it for the life of me so Im asking again. Apologies. Im not sure its an axle count issue at this point bc I received the WP F3B unit and it starts smoothly creeping around 25% like the other 6 axle engines. Anyways what are my options at this point? Live with this engine and just run it alone? or should I consider buying another, hoping it creeps like the others at 20-25% throttle so I can run smoother more matched AB configurations? Will it degrade the B unit or vice versa if I run them together for a long time despite their difference in throttle response?
 
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D&J RailRoad

Professor of HO
#2
I would start with removing the shell and checking the drive train to see if anything is binding.
I think this is a DC engine so there would be no tuning of a decoder.
Check the trucks for free movement by disconnecting them from the flywheels and rolling them on a table.
 
#3
I would start with removing the shell and checking the drive train to see if anything is binding.
I think this is a DC engine so there would be no tuning of a decoder.
Check the trucks for free movement by disconnecting them from the flywheels and rolling them on a table.
took it apart no binding of wheels in trucks..no binding in motor or universals..contact points from trucks to pickups are spotless....perplexed at this point. Must be something or some characteristic in the motor itself that is keeping it from moving at lower throttle . Its DCC ready btw so I could prob tune it out with that I guess.
 

D&J RailRoad

Professor of HO
#4
I just realized this is an N scale loco. I don't have experience in troubleshooting them. Much smaller than HO.
Is there anyway you can confirm that the flywheels aren't rubbing against the shell?
 
#6
Have you broken this engine in yet?
oh yeah..its been run all night at least 3 times at 40%..its super quiet in fact and probably one of the smoothest running engines I have.
I just realized this is an N scale loco. I don't have experience in troubleshooting them. Much smaller than HO.
Is there anyway you can confirm that the flywheels aren't rubbing against the shell?
Yes I ran the loco without the body on. The flywheels aren't scored either from chassis contact.
 

tootnkumin

Well-Known Member
Staff member
#7
There's something I just remembered about a Genesis loco I got. It would fail to move again at times after stopping. So I ran it without the shell on and marked the position of the flywheel with a marker pen when it did at T.D.C. It showed that whenever it stopped it was at that same position. I figured it had a break in the windings of an armature pole. Not familiar either with the innards of N scale motors, but maybe something similar but can overcome it once the volts are raised. I would suggest a replacement motor be obtained.
 
#11
Just to clarify. Is this fitted with a silent DCC decoder, or with sound? And you're running it on a DC powered layout with other engines that are DC only?
I found a piece of paper in the case that says " the unit is equipped with a train control system (TCS K0D8-B Decoder)
 

tootnkumin

Well-Known Member
Staff member
#15
That decoder is obviously a non-sound type, so that rules out the need for extra voltage to be applied to get the sound operating before the engine will move, but it does have BEMF as a control option for the motor and also the ability to use momentum as a speed control. If you got this loco as a pre-owned unit, then it's possible/probable that it's been set-up with momentum adjustments made. Your other engines will not have this, being only ever intended for DC operation.

If, as I have said it may have had adjustments to it's CV's, when being run on a DCC layout, that a reset (requiring the use of a DCC control system) to default, should cure the problem.
 
#16
That decoder is obviously a non-sound type, so that rules out the need for extra voltage to be applied to get the sound operating before the engine will move, but it does have BEMF as a control option for the motor and also the ability to use momentum as a speed control. If you got this loco as a pre-owned unit, then it's possible/probable that it's been set-up with momentum adjustments made. Your other engines will not have this, being only ever intended for DC operation.

If, as I have said it may have had adjustments to it's CV's, when being run on a DCC layout, that a reset (requiring the use of a DCC control system) to default, should cure the problem.
It was purchased brand new, I'll look into a dcc controller, thanks for the valuable info!
 

tootnkumin

Well-Known Member
Staff member
#17
It was purchased brand new, I'll look into a dcc controller, thanks for the valuable info!
Unless you are intending to convert all your other engines over to DCC i.e. install DCC decoders in all of them, then a DCC system for just 1 loco would not be worthwhile. All DCC decoders made today are what is called "dual function", meaning they will operate on either DC or DCC, BUT, and it's a big but, while you can run a DCC dual function loco on a DC powered layout, using the DC controller, you cannot and must not try to run a plain DC loco on a DCC powered layout. It will burn the motor out. It's all to do with the 2 electrical wavelengths being different and incompatible. Dual function decoders have the ability to detect which type of current is on the tracks and switch over accordingly.
 
#18
Finally called Kato and the guy told me that this engine wont run at lower throttle on my simple DC setup because of the DCC board installed on the chassis is restricting the voltage compared to a non DCC unit. So now Im at a cross roads on either keeping it or selling it. What to do , what to do.
 

trailrider

Well-Known Member
#19
(Tongue in cheek mode ON: Kato makes beautiful trains. Unfortunately they are useless to me...as they are only N scale, and I model HO! ;) T-I-C mode OFF!)

There are several options available to you: 1) You could sell the present locomotive, possibly at a swap meet and buy a DC-only version. Walthers catalog shows the DC-only WP F3 for $90, P/N 381-1761202 or 1203 (depending on the road number you want). If you want to keep the DCC loco, you might have to consider purchasing a DCC throttle setup, which aren't cheap. MRC make the Tech 6, which can be switched from DCC to DC, but as tootnkummin stated, you could NOT run this loco with the DC ones without having the Tech 6 set to DC!
Here is another possibility: Remove the circuit board and rewire the motor directly to the trucks (assuming power from the "north" rail is picked up by the wheels on one side of a truck and the "south rail" pickup is from the other truck (or the wheels and the frame on one side of each truck are insulated from the truck frame and wheels on the other side of the truck. Best of luck, whatever you decide to do!
 

tootnkumin

Well-Known Member
Staff member
#20
Finally called Kato and the guy told me that this engine wont run at lower throttle on my simple DC setup because of the DCC board installed on the chassis is restricting the voltage compared to a non DCC unit. So now Im at a cross roads on either keeping it or selling it. What to do , what to do.
That's unusual. That generally only happens with sound equipped DC/DCC locos, where when running them on DC, they need more throttle voltage applied to get the sound started, before they will move. It would seem Kato's purpose with this model has been to build in this delay into a silent dual function board, so it can be run with other "dual function with sound" locos, on DC.

Looking back at your original post, I see you have a "B" unit for this loco that runs as your others do. Ask Kato if one of those boards could be substituted for the errant one in the "A" unit.
 





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