I am having trouble with two Athearn Genesis GP 9’s. My layout is HOscale, DCC on peco track and peco insulfrog turnouts.
I can run a MTH F 7 A and B unit, two Atlas GP 7’s, and a Proto 2000 GP 7 without any issues over all the track and through all the turnouts but when I fire up the Athearn GP 9’s they intermittently stutter especially when going over the turnouts. Thought maybe it was the frog area but under closer examination it is not always when they hit the frogs.
Any ideas / suggestions on troubleshooting these two loco’s…they look good but sure don’t run consistently.
First thing is to check the wheel gauge. If they all check OK, next thing might be a factory reset on the decoder. After that check whatever contact arrangement there is on the truck to see if everything is in the right place. Then check the power leads up from the trucks to make sure they’re all connected right.
First thing to do is remove the side frames and remove any grease that has accumulated on the axle ends and inside the journals on the back of the side frames. Make sure they are clean.
If that doesn’t solve the problem, this is where the problem lies …
A simpler solution I found was to remove the the wheel / axle assembly from the drive gear and carefully tap the axle out a bit further - you only need to gain a bit more than 0.030". Something else that helps as well is to slightly deepen the groove in the truck assembly where the axle rides which will force the axle tip to come into better contact with the top of the bronze journal.
99% of the time, I’ve found making sure the contact surfaces are clean and dry and filing out the truck axle grooves cures the problem. Adjust the axle length as a last resort.
Mine initially did the same thing. I couldn’t quite diagnose a specific problem area in the mechanism or wiring. I checked electrical connections between the trucks and decoder and soldered every one I could to eliminate loose wires as a culprit. I cleaned what I could without complete disassembly.
Performance improved little by little, and with enough running time the stalling disappeared. I’ve heard since that similar problems have been experienced by other owners of Genesis geeps. They all seem be cured as much by running as anything.
Another potential problem with Genesis mechanisms concerns contact between the axles and the bearing strip. Sometimes the axle ends don’t make good contact. You may be able to gently tap the half axle through the wheelset a bit until enough protrudes into the bearing to ensure better contact. (EDIT - looks like Mark already explained that one.)
Does Athearn have the same drive mechanism on most of their diesels? I have a RTR RS-3 from the most recent run and its doing exactly what you described. I tried soldering the wires and cleaning but same results.
The RTR engine still use a truck design like the old blue boxes. The trouble I found with those is that they paint the metal side plates on the truck housing black to hide them. Paint gets in the slots where the bronze bushings ride and acts as an insulator.
Remove the axles and use an x-acto blade to scrape all three sides clean of any paint residue.
While you have your RS3 apart, check for cracked axle gears as well. I’ve had three Athearn RS3’s through my shop and every one of them had two or more cracked axle gears !
May sound like a foolish question, but did you clean the wheels first? many of my new Atlas engines would do exactly as you refer straight out of the box. Others have covered all other issues quite well. Hope you solve the problems.
If the wheels are in gauge, check your guard rails on your turnouts, they may be just a little too tight for the Athearn wheel sets. I had that happen to me. They were not stalling, they were trying to get through the too tight guard rails.
Well, thank you for the responses. I have cleaned the wheels and checked the guage which all seem to be correct. I tried looking under the hood so to speak for any loose wires and the only loose wire I could find was the lights I pulled out putting the shell to the side. LOL.
I couldn’t find anything from my intial observation, although I am a rookie at looking under the hood so to speak. I placed a small amount of lube in the wheelset where the manual directed and then put it all back together and performed a reset as directed. Back to the track and the loco seemed to run right through all the turnouts at higher speeds so I let it run for close to an hour. When back to slow speeds while switching out some cars I experienced the same issue. Out on the main, it was humming along right through but at slow speed it stuttered…not a total stall just a momentary lurch mostly crossing turnouts enough to cancel the headlight on the GP9 but not a reset of other engines I have sitting in the yard.
I’ll check the guard rails and report back. Still a work in progress.
I’m willing to bet, it’s the guard rails. I experienced the exact same thing. Going fast, no problem, going slow, they would act as though they were losing track power. Try running two powered together at slow speed, I’ll bet they go through without stalling, did that and it worked. I finally pushed them without power on through the guards and that is how I found it. Not all turnouts, just a few that did that. I filed the inside of the guard rail with a flat Jeweler’s file, always testing, until they went through freely. Have not experienced any problems with any other rolling stock or Engines because of the filing.
A Google search about Athearn Genesis GP9 problems indicates that the loco is too light in weight, resulting in poor contact btween the rails and the wheels. That seems hard to believe, but that seems to be a somewhat common complaint.
You shouldn’t have any trouble adding weight to the roof of the hood, just make sure you clear the circuit board/motor. Use some A-Line stick-on weights.
I am going to approach the weight issue and see if that helps. The guard rails don’t seem to be the problem as it is not just one turnout and never consistent.
When you are done trying everything else without the proper results, do what I suggested in my first post. I’ve had six of those things through my shop that all exhibited just what you are describing. My solution cured every one of them …
“A simpler solution I found was to remove the the wheel / axle assembly from the drive gear and carefully tap the axle out a bit further - you only need to gain a bit more than 0.030”. Something else that helps as well is to slightly deepen the groove in the truck assembly where the axle rides which will force the axle tip to come into better contact with the top of the bronze journal."
Mark,
I appreciate this advise and direction…the main hestitation I have is I have never taken a loco apart and alittle hesitant.
the tasks as described are like looking at calculus for me…removing the wheel assembly from the gear drive??? I’m usually real good as getting things apart…its usually an issue getting back together that stops me from trying. Deepen the groove where the axle rides…bronze journals??? these are all foreign terms to me. I have been at this hobby for 5 years but mostly building the layout and getting structures built, and the track all laid. Just a real novice when it comes to working under the hood of these loco’s…
You mentioned “your shop”…is this something that athearn should be expected to fix or are we just left to fend for ourselves. I mean,I haven’t called Athearn so I don’t know what to expect from them.
As ALWAYS, I appreciate all the responses and suggestions so I am just trying the ones that are in my comfort zone first and as you can see…not working yet. LOL
Sorry Bart, having been in this hobby for 40 years and doing this sort of thing as a business for the last 10, these sort of things are just second nature and we forget the fear some have when tearing things apart.
I don’t think you’re going to find Athearn making good on this situation, even though it is a design flaw in poor tolerances.
If you seriously want to fix the problem, you are going to have to bite the bullet and tear it down, or have somebody do it for you. There are three problem areas. The first is lubrication on the ends of the axles and that same lubrication in the journals that the axle tips seat into. Lubrication is an insulator and just exasterbates the poor tolerance.
The second problem is that the slots the axle fit into on the truck frame aren’t quite deep enough. The bottom of these slots is rounded, where the axles ride. A small round file will deepen these slots just a small amount to allow the azle tips to run solid in the journals.
These two steps will cure the problem 99% of the time. IF you are still having trouble, then the axle itself will need to be tapped outwards slightly to tighten up the tolerance in the journal - although I’ve yet to have to resort to that yet.
I know, it sounds intimidating, but it’s not that bad. Just pay attention to what you are taking apart and take note of where the parts go, so they will go back together properly. I’ve torn these things down, done the modification and had it all back together in about 15 minutes - I’m sure you could have the same thing accomplished in an evening at the bench.
with your nudge and a youtube video I got to work.
the first wheel set came apart pretty easy and after I figured out the wire clips on the decoder simply came off allowing the wheelset to seperate…I was able to get inside and clean out the lubrication and the found the bronze journals and cleaned those out. Filed the axle channles as you described and Soldered the wire I broke off. Actually got it all back together.
Now the rear wheelset didn’t go as well…any secrets for getting the sideframes off without breaking the tabs? the front wheelset came apart with some pressure applied but the rear one just wouldn’t budge—until of course when I broke the tab off and broke the sideframe apart. I’ll be ordering some new parts Tuesday so it will be some time before I can get this back together. I will work on the second loco tomorrow and hope that I am able to get at least once back together and running to see if this is the solution.
All in all, it did go pretty well. Just wished those sideframes were a bit easier to seperate. AT LEAST I have learned/ experienced what not to do and what to do in disassembling a loco.
as far as the weight of the loco’s…do you think 1-2 oz would make a difference? dont have any weights to try to increase weight yet…although it looks pretty tight inside the shell so not sure where the weight will fit.