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 Kato HO P42 six-month update...
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swchief3
Passenger

USA
142 Posts

Posted - 04/01/2014 :  18:45:22  Show Profile  Reply with Quote
Hard to believe my oldest Kato HO P42s are now over six months old. AMTK 68 was the first one I got, back around Labor Day, and I got AMTK 161 a week or two later.

Here's a quick look at what's happened in these last six months:

- AMTK 68's rear motor failed, and had to be replaced.

- Both units have slowed down considerably, overall.

- Both units are starting to lose speed, in spite of clean wheels, clean track, and adjusted wheel wipers.

- Both units have much better throttle response than when they were new.

Given how one motor failed, and both units have lost top-end speed, I wonder how long these things will last, before motors have to be replaced. Kato is now selling the coreless motors individually, which is GREAT. But, they don't appear to sell the wheel wipers by themselves. (At least, I haven't been able to find them on their website.) Since I've had to bend the arms on the wheel wipers, in order to improve wiper-truck contact, I'm concerned about these arms breaking off after x amount of bends. During running, the arms will work themselves back to their original flat positions, thus requiring they be bent back. As the arms get bent back to straight, motor performance degrades, going back to the surging, lagging, and otherwise erratic running that I've talked about before. I've tried putting a small washer over the center point of the wiper, but it didn't provide any additional truck contact, so I have to rely on the bending out of the wiper arms. I may try putting some improvised paper shims in between the outer truck sideframe and the wiper, to see if that cuts down on the need to bend the arms.

I still like the engines, but I am concerned about their longevity. I forgot to mention that the other three units I have (AMTK 188, AMTK 156, and AMTK 66) are running great. I have lubed the drivegear spindle sockets on all units, and doing so really helped further smooth out the running and throttle response.

I will try to get some photos of a disassembled truck, and post them ASAP.

swchief3
Passenger

USA
142 Posts

Posted - 04/01/2014 :  19:40:28  Show Profile  Reply with Quote
Here are some photos of AMTK 161's lead truck, used as an example.

First, the intact truck:



Next, the truck completely disassembled:



Here is a close-up of the main truck body/gear tower:



Finally, here is one of the wheel wipers, as bent to enhance contact:



The trucks come apart pretty easily. The outer sideframes snap out with careful manipulation, by gently swiveling top to bottom. The wheel wipers just lift out by hand. The truck bolster, worm gear plate, and motor clip require flat-blade screwdrivers to remove. The motor, its flywheel, and the worm assembly will lift out from the center. The motor has wire leads with copper strips at the ends, and those ends need to be pulled out of their slots in the gear tower. The gear tower consists of the two metal plates, which pry apart with a flat-blade screwdriver. The drive gears are very tiny, and paper thin. They are not as heavily lubed as they appear in the photos. The pink "thing" is the heat sink, which sits underneath the motor. When reassembling, don't forget to put that little pink pad in the housing, before you put the motor back. I always forget this, and have to pull everything out again.

Anyway, I hope these photos are useful.

EDIT: I'm wrong about the pink "thing". Not a heat sink. Just a pad.

Edited by - swchief3 on 11/24/2014 21:45:53
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swchief3
Passenger

USA
142 Posts

Posted - 04/02/2014 :  23:00:05  Show Profile  Reply with Quote
Now, I am all the more concerned about these engines' longevity. After singing the praises of my newer units (AMTK 66, AMTK 156, and AMTK 188), I now have to take some of it back. AMTK 188 is OK, but AMTK 66 has now slowed down, same as 68 and 161. AMTK 156 is now inop, as I accidentally snapped one of the motor leads on its rear motor. With that lead broken, that motor no longer runs. The solder points on those motor leads (see photos above) are extremely delicate and, as I just found out, they will snap very easily. So, if you have to take the motor out of the truck, you'll need to be super careful when you pull the leads out of their sockets. This is another Achilles' Heel on this engine/mechanism.
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swchief3
Passenger

USA
142 Posts

Posted - 04/08/2014 :  05:55:16  Show Profile  Reply with Quote
Replacement truck for AMTK 156 came in today (Monday, April 7th). Popped it in, and the engine now runs beautifully. All five P42s are running better than they did a few days ago. Running is solid and steady again, whereas several days ago, they were all over the place. For the life of me, I can't figure out why these things are so variable. Or, perhaps, "temperamental"???

I'm going to put AMTK 156 on the road tomorrow, and I have done nothing to the new rear truck, other than install it. No tweaking whatsoever. Its test run was fantastic, so we'll see how it does running lead on my eastbound Southwest Chief.
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swchief3
Passenger

USA
142 Posts

Posted - 04/20/2014 :  00:28:01  Show Profile  Reply with Quote
I think I've finally solved my problems with my oldest units. AMTK 68 and AMTK 161 have been slow, and have been losing power. The 161 was the worse of the two. It appeared that the 161's rear motor was about to fail. I checked the truck, sans motor and worm assembly, and found that the truck had binding. I swapped trucks, taking one whose motor had been compromised, and put 161's rear motor into the "new" truck. The motor and locomotive ran great! Went back to the original truck, and compared it to the one I'd swapped in, and stumbled into something interesting, and something I hadn't expected. The top drive gears (the white ones) sat differently in their towers. The support arm that holds that top drive gear in place is significantly different from the other arms. The arms that hold the lower drive gears are metal, and are molded into that half of the gear tower. The top arm is PLASTIC, and it popped out on me when I took the truck apart. Turned out, that plastic arm had worked itself out of position, and was thus screwing up the drive gear's ability to mesh properly with the worm assembly. Remounted and repositioned the plastic arm, reassembled the truck, and... no more binding! And, no more noise! Plus, the current draw is now back down to where it should be.

Holy smokes! Wish I'd realized this sooner. So far, the 161 and sister unit 68 are running better than ever. I haven't noticed any more power loss. Also, straightening out the wheel wiper arms and using a paper shim to keep the wiper in continuous contact with the inner side frame is working nicely. Throttle response is really good.
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swchief3
Passenger

USA
142 Posts

Posted - 04/21/2014 :  05:53:34  Show Profile  Reply with Quote
AMTK 68 is slow and weird again. Very frustrating. May have to bend those wheel wiper arms again. And, I made a mistake in the above post where I talked about the drive gear arms. They're all plastic, and they're all press fit. I've found a few that were either not fully pushed in or askew in their housings.

UPDATE: Bent wiper arms again on the 68, and it perked up. We'll see how long it lasts.

Edited by - swchief3 on 04/21/2014 16:19:12
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swchief3
Passenger

USA
142 Posts

Posted - 05/03/2014 :  16:32:01  Show Profile  Reply with Quote
Very frustrated with all of these engines right now. AMTK 68 is very slow, but somewhat steady. AMTK 66 has lost some speed, but is somewhat steady. But, the other three, (AMTK 188, AMTK 156, and AMTK 161) are all over the place. They race away and surge like crazy! The 156 and 188 are the worst offenders. With the throttle open to only 30smph, these engines are probably doing 95-100smph, surging wildly, and are nearly hitting their maximum of 12v. Cleaning tracks and wheels makes no difference, and the tweaks are ineffective. I recently ran AMTK 188 and AMTK 156 together, pulling my usual nine-car train, and I had very little control over the throttle. The things just keep running away. They did better when I added more weight to the train (added a de-motored Athearn RTR P42 in trail position), but they still surged. Removed the weight, and the Katos ran all over creation again.

I will be contacting Kato again. This is insane. I can't understand why these things are so out of control, and so inconsistent. For awhile, they're OK. Then, suddenly, they go wildly out of control again. Very inconsistent. In the meantime, I'm putting my Athearns back on the road. They are doing much better now. Took the wire brush to the wheels on the entire fleet, and they are the smoothest they've ever been now, and have much more power. Didn't realize I was shooting myself in the foot by cleaning those wheels with alcohol on a cloth. Ended up doing more smearing than cleaning.
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swchief3
Passenger

USA
142 Posts

Posted - 05/04/2014 :  00:13:07  Show Profile  Reply with Quote
Well, I no longer need to call Kato about these wildly-surging engines. Turned out to be dirty wheels. The rear trucks on all five engines had dirty wheels, and they were dirtier than I thought. Took an extra-long spin with the wire brush, but it was worth it. All five engines are running much smoother now, and much better overall. Throttle control is now what it should be, and surging is minimal. That's a relief, especially considering I had multiple Athearn failures again. These Katos are really sensitive; one speck of dirt, and they go ballistic!

I think there's a message in here somewhere. Go Kato. Every time I put the Athearns on, they fail.
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swchief3
Passenger

USA
142 Posts

Posted - 05/09/2014 :  23:20:00  Show Profile  Reply with Quote
I called Kato this morning, and spoke with a nice guy named Leon. I told him of my concerns with how these engines surge and lag, in spite of repeated wheel cleanings, track cleanings, and the like. First thing he said to me was that no one's ever complained about this problem, and that these engines have been on the market for awhile with no complaints.

So, after that introductory comment, we went through some general Q&A, and he suggested a few things:

1. Clean tracks with cloth and liquid cleaner of choice. (I use rubbing alcohol, but have to follow with a dry wipe, to clean up the resulting sludge.)

2. Clean wheels with wetted cloth, rather than with the wire brush. The wire brush will scrape the wheels and remove the finish.

3. Try a different power pack. If possible, use one that does not have AC along with the DC. (I use an MRC Tech III unit, which has variable DC, fixed DC, and AC terminals.)

4. If none of the above works, then send the engines in with an explanatory note.

***

Well, I cleaned the tracks again. They weren't that dirty. I cleaned the wheels with the wetted cloth. Very little additional dirt/grime came off, and the engines still surged like crazy. (And, the wire brush has been getting my wheels much cleaner than a soaked cloth.) I tried a different power pack, but it wasn't a good test, because the pack I tested was old, and its reverse control didn't work, which I'd forgotten.

I'll tell you... I don't like the idea of potentially having to change to another power pack (e.g., the Kato power pack) just to run these engines. The Kato power pack, which has no AC at all, IIRC, is $70.00. But, for me, there's just something fundamentally wrong with having to use a different power pack just for these engines.

One other thing I asked Leon about this morning was the older Amtrak paint schemes, and whether or not Kato would do some P40/42 releases in phases III and/or IV. He said there may be a chance "down the road", but, right now, there are no plans to do any of the older schemes. So, it looks like Athearn will be the "only game in town" for the older schemes, the newest batch being due out at the end of the summer or beginning of the fall.

So, more food for thought...
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swchief3
Passenger

USA
142 Posts

Posted - 05/20/2014 :  18:55:39  Show Profile  Reply with Quote
Some resolution, along with some odds and ends:

I think I've solved the surging problem once and for all. When I swapped power packs awhile ago, I discovered something. I'd had a poor wire connection to my original power pack. One of the leads wasn't completely under the housing screw. Fixed that problem, and the surging is virtually gone. In checking everything else under the sun, I overlooked my power pack connection. Only thing is that the wild surging only occurred with the coreless motors. My other engines, which have open-frame and can motors, never had those wild surges. The Kato P42s have been running a lot better, and much more responsively since tightening up the track leads.

I still have trouble with my two oldest units, the 68 and the 161. They are still inconsistent in their running. Took the trucks off and ran them individually, and found that each units' trucks don't agree. In both cases, the lead truck is slow, and the trailing truck is fast. The challenge now is to get them to match. If that doesn't work, I can swap trucks around.

I went ahead and got AMTK 184. It runs like a charm. Looking forward to the 145.

Last thing. Just for kicks, I tried mounting an Athearn shell onto the Kato chassis. In terms of the shell-to-chassis fit, it was perfect! The only thing is that the GPS dome/toggle prevents a fully perfect fit. You'll either have to cut a hole in the Athearn shell, to allow the dome/toggle to pop through, or you'll have to take the toggle off. The assembly will snap out, because I bought a new PC board awhile back, and had to move the toggle from one board to the other. It was tricky. I don't remember what happened with the light settings, once the toggle assembly was off; I'll have to play around with that some time, and see. I thought I'd try the shell swap, since Kato indicated there were no current plans to do any of the older paint schemes.

So, once again, things are looking up!
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swchief3
Passenger

USA
142 Posts

Posted - 05/25/2014 :  18:24:20  Show Profile  Reply with Quote
Back to surging and lagging again, and the tweaks no longer work. Ran each unit's trucks solo, and with their respective mates, and NONE of them matched. I have six units now, and none of their trucks matched each other. And, when tested at different intervals, the results were altogether different. Very inconsistent.


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swchief3
Passenger

USA
142 Posts

Posted - 05/29/2014 :  07:37:26  Show Profile  Reply with Quote
I refuse to give up on these engines! In that mindset, I took another look at my oldest and most problematic units, the 68 and the 161. Still thinking I had binding in the trucks, I disassembled them again. Still couldn't find anything wrong, other than what I've already documented with the push-fit drive gear supports. Looked at some of the trucks on the better-running units, and stumbled into something I hadn't checked or paid much attention to prior. The plastic motor cradle caught my eye.

The motor cradle is the gray piece that fits over the top of the motor. (See photos above.) It has four "arms" on it, as well as vertical fins on both ends. The fin on one end is longer than the one on the other end. The long end has to be to the outside, where the motor leads are, and the shorter fin has to be inboard. Some of these cradles were reversed. Realizing that the long fin was probably interfering with the motor's flywheel, I turned the cradle around. Surely enough, the motor ran much better. Taking this one step further, I assumed that the short fin was sill prominent enough to interfere with the motor's flywheel. I took an average pair of scissors, and cut off the short fin. The results were nothing short of amazing. I did this on the 68 and the 161, my slowest and worst units, and they ran like a dream. And, much quieter, too! I ran these units most of the afternoon and evening yesterday, powering a ten-car train, and they were smooth, responsive and consistent the entire time. It was bliss. Ran them earlier this afternoon, as well, and they were still running great.

So, I went ahead and clipped all the other cradles. I'm running two different units now, and they are running really nicely.

The clearances in these mechanisms are very tight and close. If one little thing is out, it can wreak havoc. I'm very happy with the way these engines are running now, having gotten that piece of plastic out of the way. Long-term results TBA.
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swchief3
Passenger

USA
142 Posts

Posted - 06/02/2014 :  16:47:48  Show Profile  Reply with Quote
Back to surging and lagging again. Back to the same problems as before. I'm about ready to pull the plug on these things.
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swchief3
Passenger

USA
142 Posts

Posted - 06/06/2014 :  00:40:19  Show Profile  Reply with Quote
Back to running the Katos. I guess you can say we kissed and made up. Had to order a replacement front truck for AMTK 161. It was showing signs of binding again, account a gear support that would not stay in place. One of the motor-lead solder points failed in the process of disassembly. I went ahead and ordered the truck, rather than just the motor, because I don't trust those solder points to survive shipping... or any slips on my end. I'm getting a complex about handling those motors, as their solder points are even more delicate than the ones on the Athearn trucks. Yeek! The new truck should be in in a couple days.

As far as wheel cleaning goes, I seem to be getting a better clean when I pull the trucks off the chassis and spin them individually, rather than while still attached. I'm still experimenting with that. Not sure if one method is really any better than the other.
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swchief3
Passenger

USA
142 Posts

Posted - 06/21/2014 :  16:33:50  Show Profile  Reply with Quote
Over this last week or so, I applied a tiny drop of ConductaLube to the wheel wipers, where the axles go in, and engine performance improved dramatically. I also treated the tracks with a very light application of ConductaLube. Results were amazing! All of my Kato P42s are now running rock solid with full consist, and I have yet to see or feel any more surging. The engines are now much more consistent with speed matching, which is wonderful, and their general running characteristics are excellent... smooth and quiet. They do still surge when running light, which is weird, but I'm learning not to care about that, since it's how they perform pulling the train that matters.

Good, solid, even, steady running all this week, and then some. These things are really good now! Let's hope it lasts.
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