I have an HO Rivarossi 2-8-8-2, [the version with the 'bent' drive from motor to furthest gear box], that has me scratching my head as regards electric pick up from the rails.
It was running on the track.
Now it won't.
I have stripped it down & can get power to the motor & have the motor turning over ok when:
(1) I run the + & _ leads from the transformer directly to the motor tags.
(2) I touch one power lead to the silver colored plate that sits under the front truck bolt, where one motor wire terminates, & touch the other lead to the the brass tag, [that has the other motor wire soldered to it], that surrounds the hole down through which the first motor wire runs to the silver colored tag.
So the motor is not seized or burnt out & the wiring does not appear to have a break in it.
Thus the problem seems to be in getting the power from the rails to the brass 'tag' & silver 'plates' mentioned in (2)
I would appreciate it if someone who knows their way around the electrical side of this Rivarossi could let me know how it picks up power from the track & what to look for in tracing the problem.
I have done the obvious, (cleaned the wheels), & have a multimeter.
Thank you
Tanked
l
Rivarossi's pick up power from one side via some of the main locomotive drivers, you can look for the contact wipers that are imbeded in the frame on one side that rub the backs of the wheels. The tender picks up the other side and the power flows from the tender to the engine thru the drawbar on the locomotive. Try testing with a wire to the engine wheels, and one to the drawbar. You might have a broken wire from the motor to the drawbar screw. Also make sure the wheels on the tender and nice and shiny. You can tell which ones pick up the power, they will have a metal backing on them, the center axle in each truck on the tender doesnt pick up power, only the outer two axles on each truck. A pair of jumper wires with aligator clips on them are excellent for trouble shooting these engines. Mike
LHS mechanic and geniune train and antique garden tractor nut case!
climaxpwrRivarossi's pick up power from one side via some of the main locomotive drivers, you can look for the contact wipers that are imbeded in the frame on one side that rub the backs of the wheels. The tender picks up the other side and the power flows from the tender to the engine thru the drawbar on the locomotive. Try testing with a wire to the engine wheels, and one to the drawbar. You might have a broken wire from the motor to the drawbar screw. Also make sure the wheels on the tender and nice and shiny. You can tell which ones pick up the power, they will have a metal backing on them, the center axle in each truck on the tender doesnt pick up power, only the outer two axles on each truck. A pair of jumper wires with aligator clips on them are excellent for trouble shooting these engines. Mike
Mike
My Cab Forwards pick up power as per your outline. They have that thin silver wire running along the draw bar & won't run without the tender attached.
However my 2-8-8-2's will run without a tender & there is no silver wire up the draw bar & I can't see contact wipers rubbing the inside of wheels. My Rivarossi 0-6-0 has them though.
I tested a good 2-8-8-2 after I posted by inverting it on the foam cradle & held 1 transformer power lead onto the front truck & the other onto the rear truck & the loco ran. It also ran when I held the leads, 1 on the front chassis & the other on the back chassis.
I tried the above tests on the current 'dead' one & it did not respond.
I am wondering if I have an electrical short somewhere & how to track that down??
Thanks
You have one of the newer versions, Tanked, and I'm not sure how it's wired from your description. I have the older version Mike described, with the loco picking up one rail, and the tender the other. I also have a lower boiler half with the weight for a newer version like you have, and it looks to me like a wire had to run to at least one set of drivers, or perhaps both, since the mounts for the front & rear drivers are screwed to the boiler weight, hence connected electrically. The rear engine on the Big Boy is held on with a brass machine screw with a lug under it to which one motor wire is soldered. That sounds something like what you're describing, but I see no provision for it on the newer Y6b boiler weight. There might have been a third revision, which knowing Rivarossi would be no surprise. I think you're describing a lug, screw, and a brass rivet, but it's all pretty vague.
At any rate, a photo of the wiring inside the boiler would help with the troubleshooting.
Nelson
Ex-Southern 385 Being Hoisted
SteamFreakAt any rate, a photo of the wiring inside the boiler would help with the troubleshooting.
I can do photos tonight & that would clarify what I have going on.
Can we post photos to this Forum? If so, what is the procedure? I know how to post them to the Tyco forum - is it the same method??
You may have a look at the original parts breakdown for it on Mr. HOseeker's website.
http://www.hoseeker.org/ahminstructions.html
The center area, select the pulldown menu, he has 3 pages for the 2-8-8-2.
Hard to look at but it may help you trace the pickups.
"The true sign of intelligence is not knowledge but imagination."-Albert Einstein
http://gearedsteam.blogspot.com/
Geared Steam You may have a look at the original parts breakdown for it on Mr. HOseeker's website. http://www.hoseeker.org/ahminstructions.html The center area, select the pulldown menu, he has 3 pages for the 2-8-8-2. Hard to look at but it may help you trace the pickups.
Checked it earlier but any wires are 'coiled in space' ilo showing termination places. Plus it is a different vsn to my 2-8-8-2 (rectangular motor/straight motor to Gbox diffntl runs versus my smaller 'round' motor & dog leg diffntl runs)
I think pics are needed.
Cheers
Tanked,
You're right. The exploded diagram on HOSeeker is for the older version I have.
To post a picture, just click the picture button in the toolbar (the little tree icon) and paste the direct image link into the first line. Click insert, and that's it. I find it easier to copy and paste the IMG code from Photobucket, which does the same thing (adds the img /img with their brackets).
Photos - the wired unit is the front truck. the 1st image shows the 1st wire from the motor soldered to a brass tag [screwed down], almost in centre of the picture. It also shows the 2nd wire going down a hole to a silver tag below.
The 2nd image shows that silver tag with the 2nd wire coming in from the left & soldered to the silver tag at the bottom left of the tag. The orange circle appears to be an insulator.
3rd image is from underneath, before 2nd wire termination is exposed.
4th image is the chassis without the body. Motor is loose as I have been working on the near gearbox [closest to motor]
Thats the system - how does power get to those 2 solder points from the rails?
Okay, I think I've got it now. The rear set conducts current from its frame to the boiler weight, then to the motor through a ground strap. A wire runs from that grounded side of the motor to the bulb in the front engine, which is the wire that goes through the rivet. The wire soldered to the lug on the front frame is the front pickup and goes back to the other side of the motor.
This engine doesn't have the spring loaded plungers, and instead has those blue steel disks on the inside of the drivers to conduct current from the tread to the axle, so bad plungers aren't the problem. Is it possible there's something insulating the rear driver frame from the boiler weight? Or has the ground strap that runs from one motor brush holder to the motor housing popped loose?
One other question. You didn't by any chance remove a whole set of drivers and reinstall them backwards so that the front and rear engines are picking up current from the same rail, did you?
SteamFreakOne other question. You didn't by any chance remove a whole set of drivers and reinstall them backwards so that the front and rear engines are picking up current from the same rail, did you?
Not yet.
I'll watch for that one after I have absorbed & traced the somewhat tortuous route the current takes.
Currently stripping down the front end as the #2 wire termination silver plate looks slightly bent down at one side compared to the one on a good 2-8-8-2 I have torn down to compare the two locos.
I noticed that the one that runs has a washer under the head of the bolt that holds the front truck down & goes through the #2 wire silver plate, but the dead one does not have that washer - is that significant??
One wheel on each set of 8 on the front & rear has a thin 'brassy' 'ring' on it - what is that for?
I have a feeling they need to be on opposite sides - & they currently are.
Thanks for your assistance.
looks like they isolated the front and rear drivers to get tenderless running. Have another engine on the track and it, and if both won't run you have a short, but the other enginie runs, its an open.
Looks like the design is still very similar to my own engines, isolating the drivers prolly isnt tough to do.
I could prolly do the same thing with mine easy.
Take a throttle, wire leads on it and have the engine top off and just start poking around with the power leads, one on one motor lead, the other tracing back to its point of pickup to the wheels, and you may find the issue. You will have to do some closeup eyeballing.
The wiring is actually very straightforward, and we need to get on the same page terminology-wise. The #1 wire is the pickup wire to the motor from the front engine, and it's soldered to the lug that is held down by the valve gear hanger screw. The #2 wire is the bulb wire, and it's connected to the contact for the rear bulb terminal. The silver plate is the bulb assembly. The washer you mention isn't critical electrically, but it allows the spring to exert more downward force on the lead truck, so missing it could pose a tracking issue, but won't stop it from running. It's present on my model as well.
As Dinwitty said, they've obviously isolated at least one of the driver sets from the boiler weight. I would do as he suggests with test leads, working your way back from the drivers to see at what point it starts running. You're going to have to take it from here, because I'm typed out.
SteamFreakAs Dinwitty said, they've obviously isolated at least one of the driver sets from the boiler weight. I would do as he suggests with test leads, working your way back from the drivers to see at what point it starts running.
Gentlemen
Thank you for your assistance.
Its now a matter of putting on some Eric Clapton & fossicking all over with power leads.
Speaking of terminology, "fossicking?"
I did not read through all the answers so this may be a repeat or worthless but does Rivarossi still have a spring loaded pin that rubs against a plate to transfer the power? If so the top of the pin is a dirt magnet and may be the problem breaking the circuit.
ndbprrThank you or the suggestion. I did not read through all the answers so this may be a repeat or worthless but does Rivarossi still have a spring loaded pin that rubs against a plate to transfer the power? If so the top of the pin is a dirt magnet and may be the problem breaking the circuit.
Thank you or the suggestion.
The Cab Forward 4-8-8-2 has that pin, but not the 2-8-8-2's.
Just tested the semi- reassembled recalcitrant loco on the rails & the motor is turning over.
I suspect the inside the wheel blue disc sets may have needed a good wipe down.