Jim,
Let me try to understand the operation of the tender mechanism a little better.
Once I turn up the transformer and apply power, should the drum rotate continuously? In my case, the drum rotates only once each time I apply power, turn it off, and then apply power again. It does not rotate continuously.
Rich
Rich,
It should only rotate once per cycle as you described.
As the drum rotates current will be dristributed to different finger contacts on the drum. This allows a forward neutral reverse neutral cycle. A common malfunction in the reversing mechanism is the pawl sticking not catching the gear on the end of the drum making it rotate in the direction cycles.
Jim
Jim,
I was just about to post my latest findings when I read your most recent comments.
What you described is exactly what is happening in my situation. The pawl is sticking and not catching the gear on the end of the drum because it hangs up and I have to manually reset it each time before I apply power. Is the fixable or would I be better off replacing the entire reversing mechanism?
I am also trying to determine whether power is reaching the jack panel connections because I cannot get the engine to move when the tender is connected, although the engine works fine when I apply power directly to the jack panel on the outer connections and jumper the inside connections.
When I apply power to the tender from the transformer at the trucks, I am using a test lamp to verify power at other locations in the tender. For example, I get the test lamp to light when I put a clip on the jack panel lead where the wire comes from the front truck of the tender and the other clip is placed on the upper contact where the wire is soldered from the rear truck. However, I cannot get the test lamp to light when I put a clip on the jack panel lead where the wire comes from the front truck of the tender and then place the other clip on any of the other jack panel leads. If this is a correct procedure, it seems that I cannot complete the circuit on the jack panel because I cannot get power there from the rear truck. I hope that all makes sense.
I am so grateful for all of the help that I am getting from you guys.
Rich
The sticking pawl is fixable. First try cleaning it, then lubing it. CRC-5-56 or similar contact cleaner and a flux brush will do a good job of cleaning. If still sticking make sure there is not a burr or notch worn into the E-unit frame where the little brass “L” shaped piece makes contact, if there is use a small file to smooth the edge. Sometimes as a last resort, ever so gently bend the brass “L” shaped part so less surface area is coming in contact with the e-unit frame.
I’ve made a loco jack panel jumper, but I’ve not made the corresponding piece to test the tender. To this point I use a known working loco for tender testing.
Once the e-unit is cycling, if the current is not getting to the loco, first look at the fingers on the e-unit where they contact the drum. It should be a sliding contact configuration. All four fingers must make contact with the drum. From there on out it is wire conductors and just do a continuity check for a break in the wires to the jack panel.
Jim,
U da man !
I went over to Radio Shack and bought a spray can of Radio Shack Control/Contact Cleaner and Lubricant. I sprayed it on the drum and fingers and used a flux brush to move i
Rich,
Before you replace the harness from the reversing unit to the plug, use a soldering iron to heat the end of each pin on the plug. Sometimes reflowing the solder in each pin like that takes care of the problem.
Jim,
I liked your idea about heating the end of each pin, so I tried it. At first, I thought it would work but the contact is just too intermittent. I even tried a drop of solder on the wire end of each pin on the back side of the jack panel, but still intermittent.
I am afraid that I will have to rewire the harness. I probably have to order a new jack panel. Would you agree? Or, is the old jack panel salvageable? If I order a new jack panel, does it come with wires attached or is it just the bare jack panel. If I have to add the wires, how do you do that best? On the original jack panel, I see no signs of solder. How did they go about attaching the wires to the jack panel on the tender side?
Thanks.
Rich
Rich,
I have always been able to reuse the original plug provided that the pins aren’t loose. As long as the jack panel isn’t cracked or the sockets deformed, it can be reused as well. The wires are just soldered inside the pins on the plug. Just heat the pins as I described before and the wires will pull out. After the old wires are removed, I fill the inside of the pin with solder. Then, I tin the wire ends on the new harness. After that, just heat the solder inside the pin ans put the wire in place. Portlines sell a very nice repro 12" long harness that has super flex wire in a cloth sheath that looks like the original.
Do just as Jim says. Do not cut corners and use regular wire. The superflex wire is the best to use. If you use a stiffer wire it creates a bind between the tender and loco. To keep things straight, remove a wire solder a new on in then go on to the next.
Jim
Jim and Jim,
Thanks for the advice on the jack panels and superflex wires. I will follow your advice.
After reading these posts, I decide to open up the wiring harness and investigate whether I had a broken wire problem. Turns out, I do not have any broken wires.
So, I did some rather thorough bench testing. I will start a new thread to describe the results of this bench test. I get some interesting results, so I not only appreciate all the help so far, but I will be back to you for some additional advice and guidance.
You guys are the best!
Rich