Pickup Roller Issues

MTH parts is down at this exact moment for me https://www.mthpartsandsales.com/

Changing a pickup roller is relatively easy- the screws most likely are external and do not even need to open the shell,

I would check for continuity on the steam engine between rollers using a meter.

Also suggest using contact cleaner like DeoxIT on the roller and rivet it rides on. Then use conductive light oil examples in this topic Edit- oops sorry, bad link.

https://ogrforum.com/...l-for-pickup-rollers

@TUGreystones posted:

Hey All,

I just got my holiday trains setup, and I'm having a nightmare with 2 of my trains and pickups.  I replaced probably 6-8 sections of MTH realtrax track, did electrical testing, etc.  I also have a handcar that runs fine on everything.  The first issue is with an F-7 B&O PS3 from MTH.  I'm attaching a photo where on one set of the pickups one pickup sticks down really low, and the other pickup keeps getting stuck in an up position.  How easy/complicated is that to repair?  Can I simply unscrew the old pickup and replace with a new one??  When I manually pull it down, the train runs fine until it goes over an operating track section - after that, it stops on switch tracks (my guess is the operating track pushed the pickup roller up to the "stuck" point).

The other is this Mohawk Steam Engine from MTH (https://mthtrains.com/30-1834-1).  I'd say it has never run great, but I'm wondering if one of the pickups isn't even working?  Is there a good way to test that??  Last year I got it to run pretty consistently.  This year, it will barely move an inch and then just shuts down.  There has to be some sort of electrical connection issue.  Any suggests would be greatly appreciated.  My 4 year old engineer has been very disappointed so far this Christmas!! 😞

Things I've tried:

• Replacing track sections and checking with a multimeter
• Oiling everything
• Using WD-40 contact cleaner on the rollers and track to try and clean everything (https://www.wd40.com/products/contact-cleaner/)

Thanks, again, for whatever help you can offer!!

Gratefully,
Seth

Before we get crazy let’s take an ohm meter and check for Continuity between the pickups. If that is fine take an eraser and clean the rollers, the nice thing is the eraser will never damage or remove any metal/steel/copper.

sorry did not read the whole post, go to HD they have a spray that is a contact cleaner lube photo enclosed. Use very sparingly

simple stuff first

OK, parts came back up but I'm not finding a breakdown for the F-7 mechanical in PS3.

Tip- when searching for pickups, the listing might be with hyphen so I just use "pick" and then refined with "double" for the F-7 style as shown.

You then can click on the picture icons and also measure and compare yours. Specific other details, yours are insulated rollers on the ends (so they don't show out switches and activator tracks)

Breakdown on that steam engine

https://www.mthpartsandsales.c...lists/304?type=lists

All - you have been so helpful!  

For the Mohawk: I tried the eraser idea that @ThatGuy suggested - no go.  I also checked continuity, which showed as non-existent (ie 0.L) until I used the eraser.  After the eraser I rechecked and had a resistance of 0.  I’m half wondering if the issue could be with the grounding?  I tried the eraser on that metal plate that pushes against the rear wheels and tested.  The engine moved about .5 inch and then shut off.  I can also see the amps drop on my Z4000 when the engine shuts down.  I ordered the DeoxIT that @Vernon Barry suggested as we live in the boonies and couldn’t find it at Walmart.  I’ll give that a shot when it gets here in a couple of days.

For the F7: Thanks for the input on finding the rollers - it’s unfortunate they don’t have my model on the site yet!  I came down with the flu or something, so I don’t have energy to measure it all now, but I’ll do so maybe tomorrow to figure out the right part.  Your tips are so helpful!

Thanks, again for everything!

You mentioned RealTrax.  Some RealTrax came with a black coating on the center rail that, in my experience, interfered with reliable electrical pickup.  I used an abrasive eraser to remove the black coating.  Then I had to go back and remove it from all of the pickup rollers as well.  If your RealTrax has the blackened center rail, you might choose to do the same.

There are some talented MTH techs on this board that could add a pickup roller to the Mohawk's tender.  (This job requires some custom engineering.)  Doing this would greatly improve the number of power pickup points, and net you more reliable operation.  Shame on MTH for NOT putting a pickup roller on the tender, in the first place!

@Ted S posted:

You mentioned RealTrax.  Some RealTrax came with a black coating on the center rail that, in my experience, interfered with reliable electrical pickup.  I used an abrasive eraser to remove the black coating.  Then I had to go back and remove it from all of the pickup rollers as well.  If your RealTrax has the blackened center rail, you might choose to do the same.

There are some talented MTH techs on this board that could add a pickup roller to the Mohawk's tender.  (This job requires some custom engineering.)  Doing this would greatly improve the number of power pickup points, and net you more reliable operation.  Shame on MTH for NOT putting a pickup roller on the tender, in the first place!

How would I go about finding those people?  I do have an MTH dealer about an hour away that does repairs - I’ve thought about taking it to him… I wanted to see how much trouble shooting I could do before taking that route.

If the problem is with the roller's conductivity, I like using these soft, minimally abrasive balls in a Dremel to clean and polish them up - available on the big A.

If a pick-up is getting stuck either in the up or down position, perhaps you can insert a tiny, flat-bladed screwdriver in-between where the pick-up rivet fits into the pick-up frame and open up a small enough clearance so it doesn't bind anymore.

Does the pick-up get stuck when you manually press it up and down with your finger ?

@Richie C. posted:

If the problem is with the roller's conductivity, I like using these soft, minimally abrasive balls in a Dremel to clean and polish them up - available on the big A.

If a pick-up is getting stuck either in the up or down position, perhaps you can insert a tiny, flat-bladed screwdriver in-between where the pick-up rivet fits into the pick-up frame and open up a small enough clearance so it doesn't bind anymore.

Does the pick-up get stuck when you manually press it up and down with your finger ?

@Richie C., thanks for the suggestions. I just ordered the balls... I'm willing to try anything at this point!

As far as the pickup that gets stuck, I just got the specific part # from MTH - I'm wondering, though, if I can pull it off and slightly bend the piece that keeps getting stuck.  I'm honestly not sure where it's catching.  I will try your suggestion with a screw driver, too.  

The colors of the "balls" represent different grits, but they're all pretty close. Also useful for cleaning train wheels, wheel flanges, axles, wipers and other things I haven't thought of yet. They have a very thin shaft which some Dremel's will not close tight on, in which case you might have to buy an adaptor for the Dremel.   

I'd try simply spreading the clearances a little where the pick-up flange sits in the pick-up frame, before removing it and bending it. In fact, if you have to remove it, I'd try lightly sanding or filing the edges/surface of the flange with a sanding wheel or stone using a Dremel, before bending it. 

It is easy to find an MTH service tech near you.

Go to the MTH website, click on Service, click on Find a service center - follow instructions.

Bruce