I did a thorough cleaning over the last two days on my GP35's and I've encountered a problem with two of them since. One of them, while it runs great going forword, now it runs very slowly in reverse even with the throttle in the same position. It must have been something I did during my cleaning even though I was very careful, (at least I thought I was) in making sure everything got put back in the same place as it was before. I have taken it apart twice since and I just can't figure out what the problem is. Could it be that maybe when I put the two frames back together I screwed them in too tight causing the mechanism to bind? Could the problem be with the springs? Or could the problem be in the wheels, wheel wipers or gears themselves. I hope someone can help because this is one of two best runners. The second problem I have is on the third GP35. Again I cleaned it thoroughly and put it back together but when I put it on the track to test it, all I could get was power to the lights. No movement in either direction, just light. So I took the body off and took a gander, but couldn't see anything amiss. I touched the circuit board and she moved a bit. I touch it again and the engine moved a tiny bit again. I jiggled it back and forth a tiny bit and the engine moved very slightly. Then I put my thumb and finger over the area where the springs are and the engine moved as long as I gently squeezed in this location. Again could this be a problem with the springs or power pickups? Could the circuit board be damaged in some way? To be blunt, this is the first time I've ever done such an in depth cleaning on these and believe me when I say, they were pretty bad. Lots of fuzz, lint, bits of foam, hair, and just plain dirt and I was sort of flying blind here, not really knowing what I was doing. Obviously I have done something wrong, I just don't know what. I have a show to do in three weeks and I need all my 35's up and running so any help would be greatly appreciated. Incidently, I ordered a couple of sets of springs just in case the problem is there. Unfortunately, it will be two weeks before they get here and that won't leave me a great deal of time to install and do testing. Thanks Ken
Hey Ken, Sometimes I have noticed that when the circuit board is pulled out at any angle, the curved part of the frame can open up just enough to not let the board get good contact. When you push down on the board, you are helping get better contact. Use an ohm meter to check from the frame to the board right next to the contact. If this is the problem, pinch the frame back together again. But take your time and don't overdo it. Just a tiny little bit each time. If I remember correctly, there are rectangular bushings in the frame that are on each side of the gear the shaft ride in. If they are not oriented right, they will bind. Also make sure you have not overtightened the screws. This is all I can think of right now. See if others have anything to add.
Thanks Dave. I'm not quite sure I understand what you're saying about the circuit board but I will check it. Also the bushings I takr it these are the ones in the frame ends that the worm gear rides in. Yes I will chek them too. I wondered about the screws. I'll loosen them off a bit.
Ken, The screws being too tight is the most common culprit on a GP-35 that won't move. And yes the bushings are the ones in the frame ends. David
Just one more thing. Is there and easier way to get the shell off the chassis. Even with using the toothpicks as it says in the servicing instructions, I struggled with each one for a good 20 minutes trying to get the shells to let go. I ended up have to gently pry them off with a flat screwdriver, but there has to be a simpilar way. Perhaps a little bit of vaseline on the corners to help it slide easier?
I usually just pull off the fuel tank and hold onto the frame. Grab the top and pull straight up. Don't hold onto the truck frames as they will pull off sometimes. Hope this helps. David
About poor running of serviced locos it's indeed likely the two chassis halfs are too tightly pressed against each other. I've experienced the same problem after servicing a Geep stalled by a piece of junk. After reassembling the two chassis halfs running was jerky and slow. After untighting them the loco now runs OK. Dom
Ken, take the truck frames off and you will find it much easier to insert the tooth picks, screw driver blades, etc into the tiny space to remove the shell. There's nothing quite like having more room to insert the necessary tools for shell removal...
Thanks Dom and Dave. I did just that. Took it apart and back off all six screws and this engine ran much better in reverse. HOWEVER, Now it makes one hell of a noise. Like something is scraping the inside of the frame. I am going to take it apart, yet again to see what is causing this. As for the other one with the circuit board problem, I tried squeezing the slots tighter, but this didn't seem to have any affect, yet when I squeezed with my fingers, it wanted to run. I was thinking that maybe the loops where the bottom of the springs attach to the motor might not be positioned quite right so I bent them both outward just a touch but before I could try that to see if it worked, I broke one of the springs. There's no way to reattach it, so I've ordered a couple new set of springs. I'll let you know what I discover with the first one about the noise. Thanks for your advice. I have 4 GP9's that should be clean as well, but I'm reluctant to make the attempt. I don't want to screw anything else up. Oh and about the shells, I tried both methods to remove them from the chassis, it was still a struggle. I was thinking about grinding down the corners of the chassis behind the points just a tiny bit. This seems to be where the problem seems to be both on removal and replacement. What do you think? Ken
Well I took that noisy Geep apart last night and I'm damned if I can find why it is making such a horrible noise. I checked the worm gear, the bushing, even the gear tower on the truck and it all seemed to be proper and correct. I put it back together and ran it without the shell and it still makes this noise when in reverse. I sounds very much like the worm gear is rubbing on the frame but I saw no indication of it. If I keep taking this engine apart and putting it back together again, I'm going to damage the springs or circuit board and then it will be useless. Before I do it again, has anyone any suggestions as to the possible cause and what I should look for. Believe me I'm stumped.
Just an idea. Could be the trucks. Put the frame together without the trucks and put power to the frame halves. Then you can eliminate the trucks as a culprit. Sometimes debris can get in the gears inside the trucks. And you can see inside the frame how the gear on the shaft is turning. Hope this helps.
Thanks again Dave. I cleaned both trucks thoroughly in the beginning; wheels, wipers, gears, frames, I went over everything at least three times, but I'll give it another go. Maybe I missed something.
It could also be the top gear (not the show ) of the truck not meshing right. Try a truck from another GP-35 one at a time.
Hey Dave. I think I solved the problem. I took that Geep apart and checked the positioning of the worm gear and top gear. I put it back together and tried it and it was still noisy, so I took it apart one last time and swapped the rear truck for the front one, and low and behold, no noise. It runs smoothly and quiet in both directions. I really don't know if that was the original problem or not, but hey, it works. I'm not messing with it any more. I do have to ask though, is it normal for the worm gear to have a certain amount of backward and forward play in the bushings? I was looking it once together and there seems to be about a 32nd of an inch or less play in the worm gear. It doesn't seem to affect the operation at all, but I just wonder if supposed to be like that? There doesn't appear to be any play at all in the rear gear. Today is not my day with these things. I dropped one of my SD40's on the floor and broke one of the trucks. Actually it was one of the tabs that holds the truck into the chassis when assembled. It's useless to me this way and there is no way to successfully repair it even with Krazy Glue. It just slipped out of my fingers. Ok now I have to ask, is it possible to get another truck assembly from MTL or somewhere else or do I have to replaced the entire chassis? If anyone has a truck for an SD40 that they don't need, or even a complete chassis, I'd be interested in purchasing either. Joe if you're on here, do you have any extra SD trucks kicking around the shop? Thanks again Dave. Once I get the springs I ordered, I'll try to get the circuit board problem on the last Geep fixed. If not, I'll be back to you for more suggestions. I never thought that cleaning these little guys would be so problematic. Ken
Ken, Glad I could help. Another suggestion I got from someone is to take the circuitboard off of the frame and clean everything in one piece in an ultrasound cleaner like used in jewelry. Use air to clean and dry everything off and relubricate. This gets away from the reassembling in the wrong order thing.
I've been wondering about an ultrasonic cleaner. Would you use water for that or some kind of cleaning solution?
I would never throw a locomotive chassis into an ultrasonic cleaner (think about the motor). To clean various locomotive chassis without disassembly, I always used regular strength contact cleaner (developed for cleaning electronics), than blow dry the chassis with an air nozzle.
