7127 Hesitates in a turnout......


PrairieKnight

Active Member
I am having an issue with a Walther's Proto GP 60 Locomotive. This particular locomotive - 7127 will hesitate ( slow down and sound cuts out} as it pulls forward through one of the 17 Atlas remote snap switches on my layout. This is at speed step three on my NCE Power Cab DCC system. The locomotive will continue through the turnout and the sound powers back up...unless I have a twelve car train or more, then it stops until I push it through the turnout.

7127.jpg

I tried uploading a video of this happening but I could not do it. This photo is at the exact location on the snap switch where this occurs. Let me try and explain further: The turnout is a right hand Atlas #4 remote snap switch. One of 17 on the layout. #7127 is the only locomotive that has this hesitation when going forward through this particular turnout. It does not do it when in reverse or when going forward the opposite way through the turnout. I have a second Walther's Proto GP 60 and a Walther's Trainline GP 9 that never have issues going through this turnout. My Proses three light voltage gauge shows three lights worth of power through the entire turnout. I have metal wheels on all of my rolling stock and clean the track with alcohol once a week if it needs it or not. Oh..and one more thing...7127 will not do this every time it goes through this particular turnout. It will pull through fine for three consecutive runs through and then the hesitation kicks in on the fourth or fifth and continues until I stop 7127 and cuss out the engineer. :rolleyes: I will then use a small dental brush with alcohol on the contact points of the rails and I get a smooth pull for three more runs.

I am wondering if there is an electrical pick up associated with the forward starboard side truck on 7127 that needs to be adjusted or cleaned. I have no idea if this is the issue or how I would correct it. I really do not think that it is the turnout as my other locomotives pull through just fine. Any thoughts or suggestions are greatly appreciated.

I
 
That is the identical problem I had with my Athearn GP 38-2 when going through certain turn outs. The front truck had a pick up wire broken off the front truck power strip and the truck wasn't getting any getting power up to the decoder.

Test the locomotive by lifting either end of the loco off the tracks and see if it's still getting power and then reverse the procedure for the other truck. This will tell if is a power pick up problem with one of the trucks.

Also check for dirty wheelsets.

Greg
 
I second this notion, put the engine upside down in a cradle(bowser sells an excellent one that ALL modelers should have) and apply power to each wheel set and see if she runs, If all wheels are clean and picking up power, check the gauge of the wheel sets using the NMRA gauge and see if one is narrow. A narrow wheel set can sometimes touch the point rail creating a momentary short, which causes the sound to resent or the model to stall. This seem to be more common on the middle axle of 6 axle units, but I have had 4 axle units do this. Cleaning up shorts is one of the "joys" of brass diesel ownership(all of my current power is OMI brass now). But I have dealt with most other brands. Mike the Aspie
 
If these turnouts are NOT power-routing (I am not familiar with the turnouts you describe), it could be that the points rails momentarily lose contact with the stock rails or with any wiper tabs if they are present. The Atlas turnouts, I have heard, have poor connections between the closure rails and the points rails. The points can wobble a bit, or don't lie flush and tight up to the inside face of the stock rails, but particularly when a weighted axle runs over them and causes them to wobble a bit at the joint.
 
hesitate ( slow down and sound cuts out}

100% that's a power loss/pick up problem.

Mostly likely one of the trucks is not picking up power properly from one side (bad contact or broken wire) so when the truck that *is* picking up power on that side hits a dead spot (insulated frog, or a point rail that doesn't have its own power feed and does not make proper electrical contact to the stock rail) the engine loses all electrical power.
 
All Atlas switches are the all-live type.. Look real closely at the little rivets that the point rails swivel on. Pos. one is lose and thus intermittent. Another possible cause is that Atlas #4's are notorious for stall outs due to having plastic frogs..#6 and up have metal, powerable frogs, with several ways of accomplishing this..(Hex frog Juicer/ Caboose ground throws). Another may be that the acute curve of the #4 that the loco is negotiating is causing its front truck to lift the powered, right side wheels up a tad causing an 'open' (not a short).
 
I am sorry that I have not posted a response sooner but it has been a busy week at work. The wheel sets are in line with an NMRA gauge. I have read about the wobble on these turnouts. I will check the rivets and see if there is a loss of contact on the rails. I am still looking into the possibility of a bad contact or broken wire on the right side of the front truck. I am not sure how that works or how to clean and/or replace a bad contact or a broken wire. Do you know of a web site or YouTube video that could tell me more information about contacts and wires on locomotives? That is interesting about the front truck lifting and causing an "open". I will also try a Caboose ground throw on that particular turnout.

I will hopefully get a chance to work on this issue this weekend after I am done looking for my Easter eggs on Sunday morning :p
 
PrairieK, You can not power an Atlas #4 because the frog is plastic..Caboose does offer a power-routing ground throw, but they're tough to get used to assembling and wiring in..I've done many.. A more expensive, all metal #4 is available from Walthers or ME ? Perhaps $25-$35...
If this is the only switch the loco stalls at it has to be the switch, not the loco..
 
On some of the Proto 2000 engines I have, the trucks have "lugs" for the wire feeders, and the wire is secured with a "push-on" rubbery "wire retainer".

It's possible that one of these may have worked loose on the problem truck. It might even be "intermittent" -- just loose enough to "cut out" the power pickup now and then, if flexed the right way.

It's a little work to actually expose these things, however.
 
I would say that step one, is with the locomotive upside down, and using test leads, check that each and every wheel is picking up power consistantly. If that checks out, then the switch or point rails is having an issue. I have had some of my Atlas point rails with a bow in them, so that they sometimes would touch the backside of a wheelset and cause a momentary short, but not enough to trip the breaker, just cause a hesitation as the locomotive traveled thru the turnout.
 



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