Repower Athearn H0 CF-7
#1
I did repower two Athearn H0 CF7 with A-Line repower kits today.
The result is not as good as expected. The motor runs ok but the noise is still a problem. I have two observations:

1. The flywheels are glued on the shaft. There is a good fit but it is not balanced. The entire assembly is vibrating. It gets worse on higher speed.
2. The motor is glued to the mount cradle that is glued to the engine frame. There are no rubber shock absorbers anymore.

I'm under the impression that the advantage of the better motor is eaten up by the unbalanced motor assemble and the fixed mount of the motor to the frame.

I would be glad to hear your opinion and some tips how you handle A-Line repower kits in Athearn engines.
Reinhard
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#2
I've never used the A-Line re-powering kits, but I've re-powered dozens of locos. Most were fixed in place using silicone sealant, simply pressing the motor into place. I usually powered the loco immediately after putting the motor in place, just to see if there were any problems - of course, the torque of the motor will cause it to move, but it's usually easy to get it back into position.

Did you "seat" the brushes before installing the motor? NWSL suggests attaching power leads to the motor, then running it at medium speed with no load, lightly tapping the brush-end of the motor case using the handle of a small screwdriver. You can tell by the sound when the brushes are properly positioned, as it will be quieter - if it gets noisier, keep tapping until it quiets down. Wink Goldth
If you can disconnect the driveshafts from the motor, you should be able to perform this operation with the motor in place: while it may improve the running characteristics of the motor, including making it run quieter, it's not likely to reduce the vibrations.

I almost always eliminate the flywheels when doing remotoring jobs - many of them are not properly balanced anyway, causing more harm than good, and most are too small to be of much benefit.

While some of the problem may be caused by the solid motor mounting, I'd guess that the majority is due to the flywheels. I'd suggest either eliminating them completely, or at least replacing them with ones that are properly balanced, such as those from Timewell.

Wayne
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#3
Wayne,
thank you for the hints and tips.
- I will try to find a flexible glue. I'm not sure if I understand the term "silicone sealant" correct. We use something like that in the bath e.g. to seal the bath tube. It is flexible but I'm not sure if it is a good enough glue to hold the motor in place. May be we have someone in the forum living in both worlds who can post a German brand name.(see my update below)
- The used Mashima motor has no brushes I could optimize.
- To do it without the flywheels is a real option. With todays good DCC controllers is the fly wheel less important. I will give it a try if all other fail and I have to rework the entire engine.

The A-Line system has another weak point. It is the universal coupling set. It is of very low precision. The noise reduced after I removed it, reworked it and reassembled it with some grease.

I did a lot of repowering of German engines in the past. I used most of the time kits from a German vendor with premounted motor-flywheel sets. They have been balanced prior shipping all the time. I do really wonder A-Line thinks they can omit that step and drop of glue will do it at the customers site.

Update 1
I did search the German Google and found silicon glue. It is flexible and used on glass, metal and so on. That sounds like the real stuff. Will go shopping this afternoon :tada:

Update 2
Got the silicone like glue. I put 0,04' card stock bands around the motor at each end to have a defined distance to the cradle. In between I did put the silicone glue. The card stock strips will be removed in some hours when the glue starts setting. It will set only 0,055' in 24 hours. We will see tomorrow...

[Image: cf71.jpg]
Reinhard
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#4
The glues has been set over night and the engines are back on duty. They are considerable less noisy. The flexible glue is very well isolating the vibrations of the motor from the engine body and the shell.
Thanks again for the valuable hint!
Reinhard
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#5
I'm glad to hear that you've got those locomotives back in service, Reinhard. :tada:

Wayne
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#6
The repowering of the CF-7 happened to the Florida Midland CF-7 when I did the Florida layout. My current Santa Fe CF-7 have all the Athearn RTR motors installed. I did not want to buy another batch of A-Line motors. So I decided to swap shell and trucks of Florida Midland and Santa Fe CF-7.

That worked great but two older engines had the motor still glued in place with a not flexible glue. They were noticeable more noisy than the others. It was the right opportunity to redo the motor mount in a flexible manner.
While I scanned Walthers online catalog I saw some motor mounting pads. Double-faced adhesive tape pads about 1/2" by 1/2" in size. I have similar tape to mount decoders etc. It's original purpose it to hold carpet. I did try that double-faced adhesive carpet tape to mount the motors. That works great. It is flexible costs virtually nothing and does not transmit the motor vibrations to the body.
I will see if it will hold the motor in place for some years. However it is worth a try and easy to replace with flexible glue if necessary.
Reinhard
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#7
I've seen ads for Buhl (spelling?) can motors made in Germany. I can't remember where I saw them or who carried them here in the states, but I would expect them to be readily available in Europe. I'm wondering if you could just buy the motors and make up your own drive or adapt the Athearn drive to them? I think Northwest Shortline makes various pieces to adapt various sized motor shafts to gear boxes.
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#8
Russ Bellinis Wrote:I've seen ads for Buhl (spelling?) can motors made in Germany. I can't remember where I saw them or who carried them here in the states, but I would expect them to be readily available in Europe. I'm wondering if you could just buy the motors and make up your own drive or adapt the Athearn drive to them? I think Northwest Shortline makes various pieces to adapt various sized motor shafts to gear boxes.

There are two brands of high quality can motors used for model railroad. They are Buehler and Faulhaber. I have lots of Faulhaber motors in my German models installed. But it is not the motor alone. A German company named sb-modellbau is doing a job similar to NWSL. But they offer the motor with very good mounted and balanced flywheels and necessary couplings to attach to trucks etc. The results are extreme well. Another one man shop (Holger Graehler) is doing complete redesign of engines (incl. steam) to have a top notch drive unit. That has a steep price up to $1000... But he is not doing US models anymore. He is booked for month in advance with German models.
The problem with A-line is not so much the motor. It is the not balanced motor/flywheel assembly and low quality plastic couplings between motor and truck. They would ruin any balanced motor too.
However, with some reduced expectations and a flexible motor mount (by flexible glue or tape) are the results quite good. I did expect from A-line results as I am used to from sb-modellbau that are at least as good as state of the art Atlas engines. My fault...
I have now four Santa Fe CF-7 that run at least like some older P2K engines (e.g. GP30). I am happy with that :bounce1:

However, the reason why I posted the story about the tape is the easy handling and the easy way to attach the motor. If you are in doubt if it will fit use the tape and may be later some flexible glue. If it does not work as expected remove the tape in ten seconds and redo it. It is very easy to handle. I did some experiments with the horizontal alignment of the motor. I would not glue it five times in different positions but with the tape it was very easy to do some testing what will be the best position.
I did open one CF-7 an hour ago because a cable was shaking at the shell. The motor was still very tight held by the tape. That looked very good.
Reinhard
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#9
I did remove some ESU Loksound from some unused Athearn Genesis F7 yesterday. This night I thought how about using motor and trucks of the F7 in the CF-7?

A F7 and and CF-7 with the old RTR motor (not the A-line converted) have been disassembled in minutes. First bad new, the F7 trucks do not fin in the CF-7.
But the overall length of the F7 motor plus transmission fits perfect between the CF-7 trucks. That is what I expected and the reason why I gave it a try. It looked like the F7 motor mount would fit in the CF-7 too but that is not true. The CF-7 motor has the mount not in the middle. I glued a fitting rectangle of styrene in the motor well and mounted the F7 motor (it is the old original ROCO motor) on the new base with double sided tape. Very simple and good enough for a small motor. I did test that simple method on several engines.
The PCB of the CF-7 was easy put on top of the new motor and it was time for a first test drive.

That's it :bounce1:

The Athearn RTR CF-7 runs like an Atlas GP40!

I know that conversion is somewhat "unusual". You do not want to sacrifice an expensive Genesis engine to upgrade an RTR model. But I love that CF-7 so much and the F7 are of very little use to me today I had to do it. What you need is a good motor with balanced flywheels and a nice transmission not the unbalanced motor/fly-wheel assembly and universal transmission from A-line to make the CF-7 a great model.

[Image: Img_0413.jpg?t=1290345172]

[Image: Img_0412.jpg?t=1290345211]

ps. Yes, I still hear a very low noise coming from the RTR trucks... Wink
Reinhard
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#10
Hey, I want one of those! I remotored a CF-7 with a Proto-Power West motor and the results were similar to your original results - not that great. One of these days when I am further along on the layout, I'll be doing more work on the CF-7s. It is always helpful to see what others are doing to upgrade their locos. Thanks Reinhard.
Three Foot Rule In Effect At All Times
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#11
faraway Wrote:I did repower two Athearn H0 CF7 with A-Line repower kits today.
The result is not as good as expected. The motor runs ok but the noise is still a problem. I have two observations:

1. The flywheels are glued on the shaft. There is a good fit but it is not balanced. The entire assembly is vibrating. It gets worse on higher speed.
2. The motor is glued to the mount cradle that is glued to the engine frame. There are no rubber shock absorbers anymore.

I'm under the impression that the advantage of the better motor is eaten up by the unbalanced motor assemble and the fixed mount of the motor to the frame.

I would be glad to hear your opinion and some tips how you handle A-Line repower kits in Athearn engines.

I have not had this problem. I have a few A-line powering products. I took two E60CH electric dummy kits by American GK and re-powered them, as wall as bought an entire powered frame for a C32-8 diesel. All of these run just fine so far as i can tell, and while the E60s DO have a little bit of a vibration, i think this has more to do with the long drive shafts (due to the contours of the roof, the motors on the E60s have to be shifted closer to one end than the other).

Is is the flywheel itself that isn't turning right, or is it just not sitting on the shaft correctly?
Modeling New Jersey Under the Wire 1978-1979.  
[Image: logosmall.png]
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#12
Green_Elite_Cab Wrote:... Is is the flywheel itself that isn't turning right, or is it just not sitting on the shaft correctly?
The problem is the motor-flywheel-assembly. To do it the right way the flywheel should be mounted at the manufacture site and they should balance the whole assembly prior selling them. It is not a good idea to sell the motor and two flywheels as separate parts and hope the assembly will be balanced after they are glued together by the customer.
The shafts have a problem with length and mass. The generic one have a much greater mass then the standard shafts and therefor another potential unbalance.

However, you should read my comments with an understanding that I am much more sensitive to any kind of noise than most people.
Reinhard
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#13
faraway Wrote:
Green_Elite_Cab Wrote:... Is is the flywheel itself that isn't turning right, or is it just not sitting on the shaft correctly?
The problem is the motor-flywheel-assembly. To do it the right way the flywheel should be mounted at the manufacture site and they should balance the whole assembly prior selling them. It is not a good idea to sell the motor and two flywheels as separate parts and hope the assembly will be balanced after they are glued together by the customer.
The shafts have a problem with length and mass. The generic one have a much greater mass then the standard shafts and therefor another potential unbalance.

However, you should read my comments with an understanding that I am much more sensitive to any kind of noise than most people.

LOL! Oh the joys of aftermarket parts. Thats why at my job, we try to use Genuine GM parts when we can on our diesel rebuilds. I was only curious because i have a few of the products, and hadn't noticed this issue. Now i'm starting to wonder if the wobble in my E60 is all from that long drive shaft, but whatever, those things wobbled anyway (their top legal speed went from 120 mph to 80 because of this wobble).

I'm surprised they don't test these things or match them up somehow.

but yeah, even without the noise sensitivity, unless your running traction, you don't want the sound of a motor humming to loudly!
Modeling New Jersey Under the Wire 1978-1979.  
[Image: logosmall.png]
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#14
Reinhard, do you have any P2k Geeps? I am thinking the trucks are the same as the Athearn CF7 and should be a drop-in fit. The motor too. as far as I know.
My p2Ks are noticably quiter than the Athearn CF7s, may be a swapping of parts would make the CF7 run better. I need to tinker around with that.
Three Foot Rule In Effect At All Times
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#15
Gary S Wrote:Reinhard, do you have any P2k Geeps? ....
Yep, test is under way. Will come back with first results later today:-)

Half an hour later:
It works. The truck are a drop in part! I did not try the motor because the CF-7 have the Genesis F7 motor installed.
For an initial test a very old Geep has been used with very old truck. So the noise got actual up but that is no problem. The test proofed that up to date P2K Geep trucks fit the CF-7. That is very good new!
Now comes the emotional part... shall I sacrifice brand new Santa Fe P2K Geep truck? A unit like yours an the new bridge?

Again some time later:
If you are not brave you have to wash Big Grin I did disassemble the old trucks cleaned, lubricated and reassembled them. They are running fine. The CF-7 became even an more quite runner :bounce1:
Reinhard
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