I have two Athearn Genesis GP9's. They are approximately 5 or 6 years old. About 6 months ago they both started to hesitate or stop at slower speeds. They are DCC/Sound equipped. As they start at a slow speed, they stop and then need a little nudge to start again. The sound stops, and then slowly resumes as the locos pick up speed. It is very vexing! I have cleaned the wheels, and checked for anything loose. I haven't used them very much for the last year.
This happens on straight and level tracks, not turnouts, joints or other track irregularities. Has this happened to anyone else who own these particular type locomotives? They ran great when I first bought them. Is it something inherent in these locos? I have tested other locos on the exact same tracks, and they are fine. Any ideas? Thank you for any help.
Al
The axle points are losing contact with the copper plate on the back side of the truck side frame - a known problem.
https://tonystrains.com/news/athearn-genesis-pickup-problems-fixed/
The only way I've cured that is to remove all the wheel sets and tap each axle further outboard about 0.030". Have done three like that and permanently solved the problem. Be sure to re-gauge the wheel sets properly when re-assembling them.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
That fix / repair is good to know ...
Thanks Mark. Sounds like a design flaw by Athearn. Has anyone tried approaching them and asking about sending the units back. Why customers should be fixing a problem like this after spending good money seems ridiculous. Especially when it apparently is a known problem! I looked at Tony's Trains via the hyper-text; looks like it was happening on F7's, too.
I don't have any but it sounds like I could fix it myself rather than the expense and risk of sending it back.
Henry
COB Potomac & Northern
Shenandoah Valley
The problem is the design of the axles themselves. For some reason, they put a slight taper on the end that contacts the bronze pickup plate. If they were blunt ends, it would probably be a non-issue.
The fix I described is very simple, just rather time consuming. Once you figure out how to get the bottom gear cover off, the entire process can be done from the bottom without having to take the trucks out of the chassis.
On my F7 and F7B, I put Walthers #947-1217 #0-80 brass washers on the axel ends/tips (between the side plate and the wheel face). Also looks like I soldered the wire to the side plate. They must have had those push on plastic items to hold the wires to the side plates. No more stuttering and it snugged up the side play. If I need to do another one, I may move the axles out as mentioned above.
Mark,
How difficult is it to remove the bottom gear covers? In the owner's manual booklet, looking at the exploded view of the loco showing the gears, wheels and axles, the covers look like they have snap devices at either end. When you did this, what kind of tool did you use? Maybe a small straight screwdriver?
Also, there appears to be a main gear on each axle. How do you extend the axles with the gear in place...or does the gear need to be shifted? Having not done this, I am just wondering if there is more than I can see! Sorry for all the questions, but I just don't want to get too far, and then find that I messed something up.
Thank you.
astapleford Mark, How difficult is it to remove the bottom gear covers? In the owner's manual booklet, looking at the exploded view of the loco showing the gears, wheels and axles, the covers look like they have snap devices at either end. When you did this, what kind of tool did you use? Maybe a small straight screwdriver? Also, there appears to be a main gear on each axle. How do you extend the axles with the gear in place...or does the gear need to be shifted? Having not done this, I am just wondering if there is more than I can see! Sorry for all the questions, but I just don't want to get too far, and then find that I messed something up. Thank you.
I have a pair of larger size curved tweezers that grab both latches at the same time and using the wheel axles as a fulcrum, pop both latches free at the same time. You can use a small screw driver as well, but it's a bit more tedious to release both tabs at the same time. The bottom cover holds the side frames in place as well.
Pull the side frames outwards enough to allow you to remove each wheel / axle assembly. The axle drive gear is just press fit onto the axles. Each wheel / axle just twists out of the gear. Make your adjustments to the axle length, then press each back onto the gear. An NMRA gauge will really help to get the wheels spaced properly on the gear. If you don't have a gauge, use another un-assembled wheel set to match the width.
The easiest way to tap the axle through the wheel is to place the wheel on a vice with the axle hanging through the open jaws. A couple taps with the hammer is all you need - 0.030"+ isn't much and should be measured with a micrometer as you go. Not enough won't show any improvement - too much and the wheels / axles may bind on the side frame.