Model Train Forum banner

1 - 20 of 31 Posts

·
Registered
Joined
·
35 Posts
Discussion Starter #1
I just picked up an older Mantua 0-4-0 steam loco & tender. I know that they have a reputation for contact issues. It is clean & lightly oiled. It seems to get power from one side on the tender (which has metal wheels) and the opposite side on the loco. It runs smoothly in forward or reverse when the transformer wires are touched to the wheels. On the track it runs really well in reverse but hesitates and struggles forward. Is it related to the connection between the loco & tender (flat piece of stiff plastic)? The tender wheels seem to barely contact the track and when I press down on it the loco spins and wants to take off. Like I said, I am perplexed? :confused:
 

·
Moderator
Joined
·
16,666 Posts
What happens if you flip the engine around on the track, facing the other direction ... i.e., switch the input polarity? Same symptom ... reverse OK, struggle forward? Or do these symptoms reverse?

Is there any evidence that you have or should have a weight inside the tender?
 

·
Yard Master & Research
Joined
·
10,633 Posts
That motor only sets with one screw. Clean the worm gear and try to play with the position when you tighten it down. It may be worn from that position. I have never pulled the worm gear to reverse it on the motor. I like the Mantua but don't have any. It's my choice for HO.
 

·
Registered
Joined
·
35 Posts
Discussion Starter #4 (Edited)
Flipped the engine around -still smooth in reverse and struggling forward. There is a lot of overhang at the back of the engine. It seems to me forward rotational torque lifts the back end therefore the front of the tender. Reverse rotation presses down on the back of the engine & tender. I tried removing the solid link between the engine & tender and just leaving the wire connection but same result. Pressing down on the tender does make it want to go faster so maybe still a connection issue? When I just touch the transformer wires to the wheels it runs smoothly forward and reverse. The worm gear and the 'pickup gear' both appear to be good condition. In reverse it pulls a string of cars very easily. Forward it struggles with or without a load. Any tips on how to adjust the worm gear position per T-Man's suggestion. I partially removed the bottom gear and wheels to inspect the worm gear but there are a lot of other screws under there and I don't want to mess it up. (Yes I'm a Noob).
 

·
Moderator
Joined
·
16,666 Posts
If the poor forward operation is due to lifting of the tender, and loss of full electrical contact of its pickup wheels, might adding a weight (at least temporarily, as a diagnostic) to the tender help?

I'm perplexed, though, when you say that the same symptoms happen even when you removed the draw bar attaching the engine to the tender. Doing that should likely eliminate the torque / tender lifting hypothesis. Can you inspect the wire connections between the tender and the loco?

Maybe the loss of electrical pickup is due to torque and "lifting" in the loco itself? That get's back to T-Man's line of thinking.

Wish I could offer more ...

TJ
 

·
play every day
Joined
·
4,950 Posts
Flipped the engine around -still smooth in reverse and struggling forward. There is a lot of overhang at the back of the engine. It seems to me forward rotational torque lifts the back end therefore the front of the tender. Reverse rotation presses down on the back of the engine & tender. I tried removing the solid link between the engine & tender and just leaving the wire connection but same result. Pressing down on the tender does make it want to go faster so maybe still a connection issue? When I just touch the transformer wires to the wheels it runs smoothly forward and reverse. The worm gear and the 'pickup gear' both appear to be good condition. In reverse it pulls a string of cars very easily. Forward it struggles with or without a load. Any tips on how to adjust the worm gear position per T-Man's suggestion. I partially removed the bottom gear and wheels to inspect the worm gear but there are a lot of other screws under there and I don't want to mess it up. (Yes I'm a Noob).
Hi Gord,

The Mantua's are neat little engines. How heavily used was it? Was it sitting unused for a long time? When you say the engine "struggles", is it because of electrical power interruption, or does it seem like physical binding holding the motor back? The fact that it runs smoothly when upside down with wires touching the wheels suggests that the electrical contact may be compromised only when the tender wheels (or engine wheels) are turning in one direction. Take a really close look with a magnifying glass at the strips where the current is picked up off of the tender wheels. Check if they looked tweaked or are not laying flat. If pressing down on the tender helps, that could mean that the strips may not be pressing on the tender axles enough. You could try removing the trucks and gently bending the strips so that they apply more pressure. Also check for any accumulated lint or grunge between the strips and the axles. Hey, can you post some pics of the undersides so we can take a look?

Greg
 

·
Registered
Joined
·
35 Posts
Discussion Starter #7
I have attached some pics. I still can't figure out how to put them directly into my reply.

I really like this little engine but am quite disappointed in it so far. I bought it on eBay and it was described as EXC!!. Then I find out it was untested. I can get my $9.50 back if I spend $9.21 on return postage! I'll get right on that.

I will try cleaning up all the contacts on the tender - that will be easy. I would also like to take the bottom of the engine completely off so I can get at the worm gear. I have partially removed the drive wheels but just want to be sure I don't mess something up when I take out the remaing screws.

Thanks for all the responses.

Gord
 

Attachments

·
Moderator
Joined
·
16,666 Posts
You guys know these HO locos better than me ...

Is he missing a rubber traction ring (?) on his left front loco drive wheel?

TJ
 

·
Registered
Joined
·
5,163 Posts
I just picked up an older Mantua 0-4-0 steam loco & tender. I know that they have a reputation for contact issues. It is clean & lightly oiled. It seems to get power from one side on the tender (which has metal wheels) and the opposite side on the loco. It runs smoothly in forward or reverse when the transformer wires are touched to the wheels. On the track it runs really well in reverse but hesitates and struggles forward. Is it related to the connection between the loco & tender (flat piece of stiff plastic)? The tender wheels seem to barely contact the track and when I press down on it the loco spins and wants to take off. Like I said, I am perplexed? :confused:
Gordo,

Your wire-to-the-wheels test....are you doing it upside down, or rightside up? If you are testing in an inverted position, try testing it the other way with the wires. I supect your motor may be having a gearing problem and having the engine inverted pulls the motor into a different position, allowing to to work.
 

·
Registered
Joined
·
35 Posts
Discussion Starter #10
tjcruiser - There is only 1 wheel grooved for the traction ring.

I cleaned up all the contacts on the tender which has helped a bit. It still runs poorly in forward and seems to always slow down on the same areas on the track, but all of my other engines run smoothly all around the track. In reverse it goes really fast and smooth. Still :confused:
 

·
Registered
Joined
·
35 Posts
Discussion Starter #11 (Edited)
Reckers - I tried the direct power test again both wheels up and wheels down - same thing - runs very nicely. Put it back on the track - smooth in reverse and very slow and struggling in forward. Like I said - perplexing!

Update: I pulled the bottom off the loco and have attached a pic. The worm gear looks ok but the worm gear and motor has some play along the shaft and the whole motor/shaft/worm gear assembly can be moved back & forth a bit along the shaft. Is that normal?

Also, the light wire is disconnected. Where does it hook up?

Thanks again.
If this thing is toast I'll send it back because I have been offered a refund including my ship cost.
 

Attachments

·
play every day
Joined
·
4,950 Posts
If you want to post an image, right click on the pic you want to post, select Properties, and copy the address:

http://www.modeltrainforum.com/attachment.php?attachmentid=3035&d=1275163712

Then paste the address into the text of your post, then put
on the back... and badda-bing badda-boom it shows up. :)






(My Mantua has just one traction tire too... ;))

The key to your situation is a proper diagnosis. It's either electrical, or mechanical. Either poor or intermittent electrical contact... or binding gears. This needs to be determined before the right fix can be implemented. I don't believe that you have a serious problem with your engine, so hang in there and we'll explore the possibilities. :)

If it's gears... when the motor spins in one direction, the worm gear on the output shaft pushes in one direction along its axis of rotation, and when spinning in the other direction, it pushes the other direction. perhaps it's binding against one end. You'll probably want to take the top of the engine off to expose the motor, this can help you a lot in determining what's going on. First things to check is if the bronze output shaft sleeves of the motor have a little oil on them and turn freely, and then if the drive gears have a little grease on them and move freely. If it's gears, when you rotate the armature of the motor with your finger it will turn more freely in one direction than the other.

(edit: oops... sorry, you had already posted while I was doing this one.

Greg
 

·
Registered
Joined
·
35 Posts
Discussion Starter #13 (Edited)
Choo Choo - Thanks for your help once again. This is a really nice little engine so I hope we can figure it out. I took the body off and the worm gear and armature turn smoothly by hand in both directions but I can move the worm gear/shaft/armature back and forth a bit. Is that bad or normal?

Regarding photos - When I right click on my pic and hit properties I don't get a copy option? Maybe I'm just photo-challenged?
 

·
play every day
Joined
·
4,950 Posts
Hey, just another thought. Are your engine's driving wheels geared together, or are they only joined by the driving rods? Maybe the rods are binding when the engine's wheels turn in one direction under load, but don't bind under a no load condition.

edit: A little bit of longitudinal movement is ok.

You right click to show the picture's properties, Then you have to manually highlight the 'http://" address with your mouse, then press both the "ctrl" and "c" keys at the same time to copy it... then "ctrl" and "v" at the same time to paste it into your post. :)

Greg
 

·
Registered
Joined
·
35 Posts
Discussion Starter #15
Hey, just another thought. Are your engine's driving wheels geared together, or are they only joined by the driving rods? Maybe the rods are binding when the engine's wheels turn in one direction under load, but don't bind under a no load condition.
Greg - I think you may be onto something here! Only one set of wheels are driven and the other set operates from the rods, which in this case are thin, flat strips. One side seems to have much less clearance than the other, I messed around with them a bit and it seems to have improved the forward performance. How do I go about setting them up properly? I will take some close-ups tomorro evening so you can see the exact setup.

Thanks,
Gord
 

·
Railroad Tycoon
Joined
·
23,868 Posts
Choo Choo - Thanks for your help once again. This is a really nice little engine so I hope we can figure it out. I took the body off and the worm gear and armature turn smoothly by hand in both directions but I can move the worm gear/shaft/armature back and forth a bit. Is that bad or normal?

Regarding photos - When I right click on my pic and hit properties I don't get a copy option? Maybe I'm just photo-challenged?

Another way to attach picture to a post is to click the paper clip, up top in the post box when your writing the post.
Click the paper clip then find your picture in your computer, click browse, then click on your picture and click open, then just click upload and wait for it to upload.
Then minimize the upload box and go back to the paper clip,click, then hit manage attachments and it will be attached.

I just picked a random picture.:D

6403B Tender.jpg
 

·
Moderator
Joined
·
16,666 Posts
Following Greg's line of thinking above, can you temporarily remove all of the drive rods (as an experiment) to see if that gets the loco running forward OK?
 

·
Registered
Joined
·
35 Posts
Discussion Starter #18 (Edited)
Removed drive rods - loco just spins because the traction wheel is powered by the drive rods. It spins much slower in forward than in reverse. Cleaned everything with contact cleaner and lightly oiled it up. No change - struggles forward when under load. Turning the worm gear or motor armature manually is smooth in either direction.

EDIT: I guess that means it must be in the motor drive itself?

I guess it is toast - I'm going to return it for a refund. Thanks for all your help.

Gord
 

·
Registered
Joined
·
2,138 Posts
I have had two 0-4-0s with this issue. One is the same as yours and the other was an 0-4-0T. The cast ones pre-Tyco did not use traction tires, they were more than heavy enough without them. I found both of mine to have an issue with the worm gear binding. It was only apparent under load. What would happen is that when the loco turned to go forward the motor moved slightly. There is one screw that allows the position of the motor to be adjusted slightly for and aft. This needs to be fine tuned through trial and error and then you will be all set.

These are great little engines. I have one with a box style tender, two with slope back tenders and one that is a tank engine. All can out pull many of my diesels due to their weight.
 
1 - 20 of 31 Posts
Top