As I posted in another thread I picked up a brass Shay loco. It ran fine for awhile then just shut down and stopped working. I took the body off and connections from the motor to the trucks and they seem fine. I did clean the wheels and the wipers against the wheels. I did put power to the motor directly and one time it ran and another nothing happened. There us also a third wire that was just under the gear box doing nothing, could that be for grounding purposes or maybe for the headlight installation? I think the problem is in the trucks but really have no idea what next. Any ideas or advice would be appreciated
thanks
Bruce
NYVTRR As I posted in another thread I picked up a brass Shay loco. It ran fine for awhile then just shut down and stopped working. I took the body off and connections from the motor to the trucks and they seem fine. I did clean the wheels and the wipers against the wheels. I did put power to the motor directly and one time it ran and another nothing happened. There us also a third wire that was just under the gear box doing nothing, could that be for grounding purposes or maybe for the headlight installation? I think the problem is in the trucks but really have no idea what next. Any ideas or advice would be appreciated thanks Bruce
So the issue could be mechanical or electrical. The motor is unlikely to be your problem, especially if you got it to turn as some point. Try to figure out the wiring, using an ohm meter, and look for loose wires or wipers that may be either shorting or not providing power. That loose wire is probably the problem. From a mechanical perpsective, the motor is easy to remove (if it's original). But before doing that, try to spin the motor shaft with your fingers to see if the shaft can actually make the gears and wheels turn (do not try to do the opposite - push on the engine to make the motor turn from the wheels). This engine was very well designed and it's probably fine from a mechanical perspective. But if there is a bind when trying to spin the motor shaft with your fingers, then you are getting into "complications". Before dismantling the gears, make sure you've eliminated all other possibilities.
Simon
snjroy
I can turn the motor by hand easily and if I connect my transformer directly to the motor it will run. There are three wires from this motor one wire to each truck and the third just laying under the gearbox seemingly doing nothing. When I put it on the track it sits there and the transformer acts like the loco is shorting out. I had disconnected the trucks to clean the wipers etc and the washers that were on the screws got away from me and hiding on the floor. I did have some brass washers and wondering if when I put them on they might be causing the problem? Should I maybe using insulating plastic washers?
I took a closer look at the motor and one pole has two wires connected to it each going to each of the trucks. The other pole has the wire that is not connected to anything
Also the motor is a sagami motor if that helps
OK, so the problem sounds electrical. I looked at one of my Shays this morning. Power pickup on mine is: front-right, rear-left. The rear truck is isolated by a fibre bolster. Both trucks have a brass washer. If you lost yours, you should replace it. Your's might have additional wipers installed... See my previous post about that.
It sounds like you have a can motor. If this is the case, you should have one wire from the rear truck going to one of the motor power lead, and one wire going from the frame to the other motor power lead. The front truck is not isolated from the frame and power goes through the frame. The previous owner might have soldered a wire from the front truck to the motor for power. If there are indeed wipers, then wires would need to route from there as well.
So you need to figure out your wiring. If there is a 3rd wire dangling, and there is a short, make sure that is not the source of the short. If you don't have wipers, I would just cut that wire off. So then you would be down to two wires to figure out, as I explained above.
Also, make sure you did not reverse the wheels when you reassambled it. That can be easily checked with an ohmeter (I strongly recommend you get one if you don't have one). The front left wheels should be isolated, and back right wheels as well (I think I got that right ).
Oh, and if you need to remove and reassemble a truck, one trick I use is that I put a small dab of silicone on the side of the screw, underneath the head, to "hold" the spring in place while you install it. Nothing worse than looking for a loose spring on a shop floor...
i did attach the loose wire to the frame and put it on the track and it just sat there. later today and tomorrow I will putter around with it using the suggestions you guys have offered. Wish me luck, I would like to get this going again.
NYVTRR I took a closer look at the motor and one pole has two wires connected to it each going to each of the trucks. The other pole has the wire that is not connected to anything
Maybe then I shoould disconnect one wire and attach to the other poll and leave the third wire alone?
It's worth a try. That third wire remains a mystery.
I did change the wires around so each truck is connected to a poll on the motor and the loco still sits motionless on the track, the third wire is both attached and loose. I think the trucks are the problem. They are both attached with a screw with spring. Should there be a washer between the truck and frame and if so should it be metal or non conductive type. I did have brass washers there. Also the wires are connected to a wiper setup, not sure if they are original or custom made by the former owner. should there be any washers underneath the unit and if so what type and I have a brass washer on the screw as the hole in the wiper unit was larger than the screw head. would that be ok or should I change to a plastic type?
I also had the loco on the track and put another loco on and neither would run and the transformer indicated a short
You will need to put your detective hat on to see. Since the Shay did run on your track at some point, it appears that you did something while reassembling it. The washer does not isolate the truck, not on mine anyway. It is a strip of material under the rear truck. One thing you can do is put the loco on the track, put something under one set of wheels to lift it above the track, and see which is the offending truck. The wipers might have been affected by the cleaning procedure.
I have done just that with the trucks. For awhile I thought it was the rear truck then it reversed itself and it seemed that the front truck was the culpret. Now if I hold the unit in my hand and connect power directly to the motor it runs but not if I put it on the track it shorts out. Also sometimes it requires the loose wire to touch the frame and sometimes not. Wonder if I should rewire the darn thing?
I'll head over to home depot in the morning and get some sort of device to track down this problem Thanks for the info
I suspect the wipers. Make sure they do not touch the axles or the trucks.
I got a multimeter today and tested continuity of wires motor wipers etc. Everything tested ok but still just sits on the track doing nothing. Its gotta be something stupid doing all this
I would remove the wires from the motor, and check what is shorting on the frame. I assume there are wipers on the front left and rear right.
Only the right wheels should connect to the frame. If there is a reading from your rear left wheel and the frame, then there is a short from that source.
I have never installed wipers on these - make sure they are well isolated from the axles and the frames/gears.
I tested just the wheels without touching the wipers at the same time and nothing showed on the meter. Would this mean anything? When I touched the wheels and wipers at the same time I got continuity.
Explain your testing of the wheels- wheel to frame?-wheel to wheel, which ones?
This loco, in its stock form, is not particularly complicated from an electrical perspective. Power is picked up by the wheels, which transmit the power to the trucks. The front truck picks up power from the right wheels (when sitting in the engineer's seat). The front left wheels are isolated in order to prevent a short. The rear truck is reversed, except for the fact that the truck is isolated by a plastic bolster. A wire is connected to the truck, and one of the motor poles. The rear left wheels are also isolated to prevent a short. A simple arrangement, with one main drawback: the limited number of wheels that pickup power. But that's not your problem right now.
Can you confirm that the engine did not short when you first tried it? If it did not, something happened when you did the maintenance on it. Is it possible that you reversed the wheels (front in back, back in front)? What about the trucks? They should allow some movement in all directions, but should not be too loose. There are screws that hold the trucks together. Check them to see if they are holding the trucks together, but not too tightly.
Are any wires touching the frame? The wipers are something to check for sure. As mentioned previously, the wipers should only make contact with the wheels, not the axles or the trucks. Because of the metal gears, I can't see how a wiper could work on the rear right wheels, but I'm probably missing something here.
The way this loco is set up is the wipers are on the left side wheels front and rear trucks. I did nothing to the trucks at all and from what I see I couldnt reverse the wheels as on the right side there are gears on the wheels. When I first cleaned the wipers the loco still ran for awhile then quit about and hour later. The wires look ok but I still wonder about the mystery third wire. I've tried touching it to the frame and also keeping it off and the loco still sits there.
Rear left wipers are probably redundant given that the motor picks up power from these wheels. But they should clear the frame.
Front left wipers might be shorting with the truck, frame or axle. Pictures might be useful.
EDIT : I assume you mean it shorts when you say it just sits there
Yes, front right wheel is electrically connected to the frame. One motor pole should connect to the frame, or to the front truck. On mine, there is a tab on the truck that could be used for that purpose.
it seems the front truck is the problem. I put the loco on the track and placed a piece of paper under the wheels of the front truck and it fired up. I then did the opposite and nothing happened. I disconnected the wipers from the wheels and nothing happened. I also found that the third wire when touched to bare frame caused the motor to run and when left dangling it would not run. Any ideas going forward? Thanks
The dangling wire should connect to the frame, as you found out. The front left wiper appears to be the culprit. Can you fix it or remove it?
I tried removing the wipers and also repositioning them and nothing happened. Wondering if the truck itself is the problem. Should I maybe put an insulating type washer between it and the frame or maybe put electrical tape in between?
If it's the same PFM Shay that I have, the front truck is not isolated from the frame. That's how it picks up the power from the right rail. The front left wheels are isolated to prevent the short. The rear truck is isolated from the frame and has a wire going directly to the motor. The original motor was grounded to the frame and I assume the new (can?) motor is isolated from the frame, which is why that third (dangling) wire is necessary.
NYVTRR I tried removing the wipers and also repositioning them and nothing happened. Wondering if the truck itself is the problem. Should I maybe put an insulating type washer between it and the frame or maybe put electrical tape in between?
EDIT: if you isolate the front truck, it will not pickup power from the front right wheel. Washers are probably not going to work anyway because of those metal gears on the right side.
ill mess around with this thing this afternoon see what happens