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I have two Atherarn F7A locos, one Amtrak and one SP. The SP unit works great. The Amtrak unit is very sluggish, especially starting out. Once it runs a few minutes it runs quite a bit better, but it still requires a pretty high throttle setting to keep it going.
I popped the covers off and compared the two units. I turned the flywheels by hand to see if the Amtrak unit had more resistance, but I didn't notice any difference from the SP unit. There was nothing visible that might be causing it to run more slowly.
In running the Amtrak unit, I hear a slight fluttering sound which the SP unit doesn't have. But I can't tell where the sound is coming from. I don't know enough about the mechanics of these things to know what might be the problem. Do I need to lubricate something? Any suggestions?
------------------ Trust God, love your neighbor, and never mistake opinion for truth. -Mr. Toy
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Here's another suggestion. www.rrdepot.com and scroll down to"modeltrains"
This should take you to "Fine Tunning Athearns" and CLICK.
Step 5 has a good lube explanation.
Challenger Member # 1298
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In reading your post. It sounds like there are one of two things wrong with your Amtrak locomotive.
The first might be you have a stripped gear. To fix this you will have to completely dissassemble the drive train to find the problem. It is a relativly stragiht foward proceedure and if you have the athearn assmebly instructions in hand. They will tell you where everhting goes. When the gear with the busted tooth is found, Replace it. I reccomend adding a drop of Labelle #107 oil before you stick the gear back in. When done reassemble.
The other possibility is you have excessive flash on some of the gears. again dissasemble the drive train. Inspecting each fear for exess plastic hanging off of each gear. If found. Trim it off with a hobby knife. When all flash is trimmed away. Reassemble.
These are my two suggestions for now. If iether of these do not work. Come back. and I will try to help you further.
James
Medicine Man Member # 2939
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Just a quick point. Are the wheel's clean? how about the pick up whiper's at the wheel's? How are the motor's brush's.
An old ARMY training drill to find problem's is to follow the path of flow( or path of mechanical operation).Start with the contact(with the rail)point of the wheel's and inspect/clean all contact's.Follow the path of current from one rail side,thru the motor,and down the other side.If no problem's are found,follow the path of operation. Start with the motor 's drive shaft,check for side to side play(worn bushing's),inspect the worm gear and drive gear's,ending at the axle shaft's.
Good luck on the repair
MM
Mr. Toy Member # 311
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Thanks for all the replies. It will probably be a several days before I will have time to follow up on your suggestions. In the meantime, I may just swap covers with the SP unit so I can keep my Amtrak train running.
But to answer the Medicine Man, my wheels are clean, but I'm not sure about the other electrical contacts.
------------------ Trust God, love your neighbor, and never mistake opinion for truth. -Mr. Toy
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you may want to also check the brush springs, if they are to tight that will laso cause the engine to use more current that normal to get running. Also you might want to replace the electrical wiper that connects between the trucks and the motor with a fine wire. As challenger suggested you may have some flashon the gears, you may want to disassemble the trucks and check that out also and after you reassemble them try using a few drops of pearl drops tooth polish in the gear box, this will act as a very fine buffing compound and help clean up the gears and polish them even more. Be sure to clean them up again after this treatment. also check the wheels for any build up and clean them also. For my money athearn's are the best engines for the money, I have atleast 200 of them and have only ever burned out 1 motor, plus with athearn you can always get parts for them unlike some of the other foreign made engines. Good luck.
Mr. Toy Member # 311
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Part II:
OK, I finally found time to disassemble the trucks and inspect the gears. Even with a magnifying glass I could see no visible flash. I added a teeny bit of lubrication, but when I put it all back together there was no difference whatsoever.
I guess I need to go over the electrical parts, but I'm not clear on how that all goes together. Any further suggestions are welcome.
emdman1959 Member # 2687
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Well, Mr Toy if you have tried all the ideas given to you by everyone it is possible you just may have a bad motor. It does happen. Try contacting Athearn themselves they were very helpfull with a problem I had with an engine and sent me the part for free. Also did you buy the engine new or is it used ? also how old is it? have you let the engine break in? if all else fails put it on the track and just let it run. From what you have said it starts to smooth out after a few minutes, so maybe it just needs some run time. Good luck.
Dave Jansson Member # 2233
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The stock Athearn motor (NOT the new Genesis series) is an el-cheapo thingee that costs about 75 cents to make. Spend a few bucks and get a replacement from your hobby shop.
Another idea is to clean and polish the gears. To do this take the power truck off, diassemble it (gently!) and clean them with warm water and dish soap using a toothbrush. Then reassemble it and put a dab of regular TOOTHPASTE (which contains a very mild abrasive) on the gears. Using a Dremel or some other drill, run the assembled gearset for about 20 seconds which should be enough to clean off any microscopic burrs that can cause problems. Disassemble and thoroughly clean it again, then reassemble and LIGHTLY lube the gears using LaBelle or any other plastic friendly lubricant.
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