# Reverse Unit



## robn9 (Jan 17, 2012)

I have 2 separate engines a 302 and 312 that I believe the reverse units are not working. 

I have been able to bypass the reverse units and get the motors to run.

Is there a way to test the reverse units and where can I get new ones if they are bad?

Thanks 

First time blogging!


----------



## Reckers (Oct 11, 2009)

Robn9, welcome to the forum! The reverse units are repairable: testing is essentially a common-sense process. The reverse has a solenoid that lifts a plunger in the r-unit and holds it up as long as the current is flowing. Cut the power and the plunger drops, forcing a drum to rotate one click. Power up again and the plunger stays aloft until you cut the power again: second click of the drum. If I remember correctly, both the 302 and 312 use a 4-position drum, the sequence being forward/idle/reverse/idle. Here's a great site to teach yourself repairs and service of your trains: http://www.portlines.com/afrepairclinics.htm

From that site, here's your reverse unit repair: http://www.portlines.com/portlinesclinic23.htm

They explain the process better than I could.

Nice to have you join us!


----------



## Reckers (Oct 11, 2009)

PS---you can buy replacement reverse units from Portline or onn Ebay. Personally, I'd suggest reworking the ones you have; it's likely they only need a good cleaning and adjustment.


----------



## tjcruiser (Jan 10, 2010)

Reck,

Nice link to the PortLines "clinic" posts. Lots of info there.

Hey ... any interest in creating a "Read a Manual" sticky thread with a compilation of "how to" links in the S section, somewhat along the lines of what T-Man did in the O section?

TJ


----------



## Reckers (Oct 11, 2009)

TJ, Jim "Stillakid" and I started something like that a couple of years ago, but it's all buried in the early entries of the S scale stuff. If you look in December, 2009 to January, 2010, you'll see a sequence of entries with manuals, S scale suppliers, etc. Could you arrange for that stuff to stay permanently in the front of the S scale area? I think it's a great resource list, and thank you for taking an interest in us. Let me know any way I can help!


----------



## tjcruiser (Jan 10, 2010)

Reck,

Thanks for the reminder. I went back to those old threads/posts, and found a few that I have now merged into one new Sticky thread at the top of the S section. Please feel free to edit (with my help, as needed), and add whatever content you, Jim, and other S guys would be helpful in a "must have" tech manual link reference.

http://www.modeltrainforum.com/showthread.php?t=2567

Cheers,

TJ


----------



## Reckers (Oct 11, 2009)

tjcruiser said:


> Reck,
> 
> Thanks for the reminder. I went back to those old threads/posts, and found a few that I have now merged into one new Sticky thread at the top of the S section. Please feel free to edit (with my help, as needed), and add whatever content you, Jim, and other S guys would be helpful in a "must have" tech manual link reference.
> 
> ...


Teej, thank you for doing that for us! I still use those lists a lot---I just went back and dug them out each time. I'll peruse and contact you if I see any way to tweak them.


----------



## tjcruiser (Jan 10, 2010)

Your welcome. Happy to help. Spread the word about the Sticky (and hopes to expand on it) to Stillakid and others.

TJ


----------



## Reckers (Oct 11, 2009)

Jim still comes by and reads the site----he'll see it.:thumbsup::thumbsup::thumbsup:


----------



## robn9 (Jan 17, 2012)

*Reverse Units*

Reckers 

Thanks for the information and the links.

One of the reverse units is functioning fine. 

Motor works when I by pass it, but not when I run it from the trucks. 

Not sure where to go next.


The other unit the drum does not move at all when I make contact.

I will take a shot at rebuilding it and let you know.


The forum is great. Just got into these trains.

Long story short - My older brothers obtained the AF trains when they were kids and they went into Mom's attic probably 40 years ago.

They had no interest in them, so I sorted through them and have about 200 pieces of various track, a dozen or so rolling stock and passenger cars, 4 engines in various states of non-operation and some assorted accessories.

I have cleaned up about 50 pieces of track and did a small layout for my kids for Christmas and have been hooked since. Had to pick up an engine on ebay to get it all running. 

Thanks for all the help.

I will be back with more inquiries.


robn9


----------



## Reckers (Oct 11, 2009)

Robn9, come on back often---we love solving problems with trains. 

For this one: Motor works when I by pass it, but not when I run it from the trucks. 
What you're telling me is that the reverse unit is rolling the drum as it should, but not passing the current. That suggests looking at two things: the copper surfaces of the drum and the two sets of "fingers" that ride the drum. For the drum, you want to extract it from the frame and clean it with isopropyl alcohol and Q-tips or soft cloth. Two rules you want to observe religiously: 1. Never use sandpaper for anything. 1. Never use steel wool for anything. That includes track cleaning for both items: don't even let them into the same room as your trains, for now. What you want to do is clean and polish that drum: a dremel tool with a cotton or wool wheel and some rouge or buffing compound. Think "polish" or "burnish" for this. You want to polish the copper on the drum down to smooth out any scratches. Clean any gunk out of the two ends so it'll move smoothly when you reassemble.

Next are the fingers. There are three things that go wrong with fingers, aside from failing to reinstall them correctly. 1. Dirty. 2. Bent to where they don't contact the drum properly. 3. Holes worn through the tips where they ride the drum. The answers are clean, adjust, and replace. You can order the fingers on Ebay or from Portline, my personal favorite when the Local Hobby Shop (LHS on this site) doesn't have what I need. http://portlines.com/

Put it back together and go very easy on the lube: you don't want to collect dust with a lot of oil. I like to use a Scotchbrite pad or dremel to buff the plunger a bit before reassembling; a very, very light coat of oil on the plunger, too---just enough to ward off rust. WD-40 is not a good item to use on your trains, incidentally.

Once you have it all back together, see if it's passing current. These things are very sturdy and common sense items: if it's not working, you can usually see a reason for the failure.

Best wishes,


----------

