A good 25 years ago, I had installed Ernst supper gearing on an Athearn GP9. It has worked perfectly all those years. Had gangs of fun with that locomotive on the club layout, but that is a different story. It is time again for the Youth In Model Railroading fun day where which they have a HO locomotive pulling contest. So I purchased a set of gears for my son (age 9). This is the 32:1 reduction 4-Axle Kit for an Athearn F unit.
After about two hours later he had it figured out and the gears were properly installed into the locomotive. Yes I checked his work. Well not quite, much to my surprise the locomotive would not run and, in fact, I believe I fried a motor trying to get it to run… My first thought was that he had done something wrong that was just not visible with my original “check”. So I tore one of the trucks down. Did not see a problem. I rebuilt it myself. Same problem. [:(] iAfter much head scratching and turning the gears by hand under a magnifying glass, I found the teeth of the two small PTO gears insisted on jamming with the teeth of the main driving gear. Hmmm I futzed with it for about two hours and could not get it to work. I filed a bit of the edges off, I sanded the gears a bit smaller, I trimmed the inside of the teeth for any flash that may have been there. Still no go. [8o|]
I grabbed an old metal sided Athearn truck out of the parts box. Put the gears into it. Flawless. What gives??? [:S] I just decided to use old trucks, but I found that not only did I have only 1 of the right size, but also that outside wheel axles of the newer wheels are too short to stay nicely in the outside bearing of the older metal truck. Bummer again. [*-)]
I was just about to give up when I decided there HAD to be some reason they were differnt and began I looking very close
Let us know how the contest goes. Is it DC or DCC?
Richard
Simple DC. They have a straight track that has three blocks. Power 1, dead, Power 2. There are a couplers idler cars that goes between the locomotives. The first locomotive to pull the other into the dead section wins.
Last year he went for big six axle power using an Athearn SDP40. This year the idea is to get the same amount of weight onto just 4 axles. He has that Athearn “super” weight inside plus a Cary Body, plus going to add tire weights everywhere else there is a space for them.
and Ernst is still in business I recently got a new set of them gears, theres plenty of them old Athearns out there.
Ernst is also a tool manufacturing company but they make these gears as well, probably a modeler in the bunch.
I just picked up a C&EI dirty orange SW whatver it is, not the usual SW stuff, its one of those roads that wiggles around chicago with these rather non-exciting engines, end yet they drag on doing their work. My model ran slow, opened it checked it…aha! Ernst gears already! Heavy metal shell, but Athearn drive.
Thank you that is a great tip.
I added the 6axle sets to a pair of old BB SD40’s & they are much more realistic, & they are a running lashup.
Appreciate the tip on the binding issue, on the 2 axle trucks, that was a good catch!
Make sure you have good solid electrical pickup on both sides of both trucks - if the front truck doesn;t pick up your loco might go dead when the rear one gets pulled into the dead section, ending the contest early!
–Randy
That is a good thought. Maybe I’ll solder a wire to the Athearn power strip from both truck uprights too.
I used this same kit and found that the picture in the instructions was backwards! After holding it up to the light through the paper I figured out why mine wouldn’t run properly. After reversing it ran like a champ. I have had my kit for a few years now.