0-6-0 Hesitation

[cmsluss]

Greetings all...

I have a Bachmann 0-6-0 (Smoky Mountain) switcher... in the split frame design.  If the locomotive is idle for more than a day or so... it hesitates when I put it back in operation.  If I run the locomotive at full throttle, back and forth for a bit... the performance will smooth out and the engine will run fine... until it sits for a day or so and the hesitation returns.  The track is clean, the locomotive wheels are clean, I don't understand why it hesitates.

Thanks for the help!

[James in FL]

Hi cmsluss,

It can happen for several reasons.
First let me say I don't model in your scale, and I'm not at all familiar with the design of your lokie.
I'm guessing USRA type, but if not, does not really matter. Can motor, open frame motor, again does not really matter, other than the fact open frame motors are much easier/faster to diagnose and fix.
I see this same problem in N scale locomotives all the time.

Current is going to follow the path of least resistance, starting from where the wheel meets the track and ending where the motor brushes make contact with the commutator.
Because you experience rough running (hesitation), logical deduction would dictate that the flow of electricity is at least partially compromised (resistance).
Continuity is impaired somewhat/sometimes, causing what you see as rough running, or hesitation.
That said;
Where is this interruption/impairment/resistance happening, or taking place, within the circuit, and how do I find and fix it?
That is the $64 dollar question.
I do not know your mechanical/electrical aptitude, it does not matter, and I will be safe and assume you have little to none for the sake of this discussion. I will also assume you don't have access to a muti-meter as you don't state you have physically checked for continuity within the circuit.
No foul, no harm.
None of us were born with this knowledge.
Look here;
http://www.trainelectronics.com/Meter_Workshop/index.htm

What I think is the cause;
Because you already cleaned the wheels and track,
There is a contact transfer point somewhere within that lokie where the current is passed from the wheels to the frame, possibly wheel wipers, or springs, maybe axle journals, or axle bearings.
Maybe circuit board or decoder contact points.
That power has to make it to the brushes or brush caps, check that contact point as well.
Check those places to make sure they are clean and free of carbon deposits and old lubricant.
Disassemble the lokie and clean all the old lubricant from the drive.
Degrease the mechanism.
Sometimes all the volatile component (carrier) of the lubricant has evaporated and what's left behind is a chalk/clay/cakelike crusty residue.
This could be the problem, or part of it, but not necessarily so.

Your problem maybe there. If you have checked the circuit and not yet found the root cause the last place it could be is here:
If oil has migrated into/onto the commutator, from lubricating the motor bushing, it will hold the carbon dust from normal brush wear.
This oily dust sludge collects in between the commutator plates, eventually bridging them.
When you run the lokie at full speed, the centrifugal force slings this mess out from between the plates, improving motor performance.
Two, three days later the oil has seeped back, starting the cycle all over again.
You should degrease the commutator and use a toothpick to run between the plates if you have access to do so.

Don't lubricate just because you think the lokie needs it. Side rods and related linkage the exception.
I generally check the side rods after about 24-36 hrs.
When the motor bearing are dry they will tell you so, with a high pitch squeal.
Engineering (slippery) plastics, (Delrin), generally truck and drive gears in N scale, require no lube.
A tiny dot of Teflon grease on the brass worms and a half drop lite oil on each of the motor bearings is usually plenty enough.
Do not lube a lokie going into storage and store your lokies wheels down, not on their sides.

I wish you the best of luck, tell us what you find.

[cmsluss]

Hi James

Thank you for your thorough and thoughtful reply regarding my HO 0-6-0 split frame locomotive.  The engine has electrical pick up "sleeves" on each axle.  So the power goes from the track to the wheels and transfers from the axles to the frame.  A can motor and worm are positioned in the center of the split frame.  Ideally with six pick up points,  there should theoretically be continuous power to the frame and motor.  The locomotive is quiet and with exception of the hesitation, I am happy with the performance.

Thank you again for your excellent help.  It is appreciated!

[James in FL]

Can you please direct me to the exploded view of your lokie?

Is it at all possible you could gain access to a multi-meter?

[cmsluss]

Hi James...

I do not have a multi-meter. 

You can see an exploded view of the 0-6-0 locomotive I have here: http://www.bachmanntrains.com/home-usa/dwg/dwgs/50440_HO_USRA_0-6-0_w_Short_Tender.pdf.

Thank you again for your time and thoughtfulness!

[cmsluss]

Hi James...

I was interested in your thoughts on the exploded view of the 0-6-0 locomotive.  It seems to be a split frame design Bachmann has used on several HO steam models.

Many thanks!

[James in FL]

Hi,

You asked my thoughts on this loco;
Again I don't model in HO scale and have never had the opportunity to disassemble one of these.
I have Bachmann's N scale version of this, to which I have added a Spectrum tender. It runs excellent.
IMO this model looks to be on the lower end of the quality spectrum, very basic primitive design, no bearing blocks, no flywheels, no tender pick-up, unserviceable motor, etc.
That's OK though, as that is what makes them good candidates for someone's first foray into understanding the mechanics of how they work and the simplicity of disassembly/reassembly for one to learn on. Probably won't find a better steam lokie to cut your teeth on. And not an expensive locomotive if you muck something up.

What I see is a split frame design with small contact springs that transfer the current from the frame half's to the motor contacts on the back of the motor.
I will assume basic left side/right side power pick-up through the drivers and, as you stated, theoretically six contact points.

Where I would look for continuity problems;
First is starting with clean wheels and track, and where the axles fit into the frame.
Second would be in where those horizontal springs are in contact with the frame half's, and the motor contacts. You can use a pencil eraser to clean those places both motor and frame.
In the parts page I see this:
http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_155&products_id=4443
But I do not see it in the exploded view, however if yours has it, it is yet another current transfer point that would need looked at and cleaned as well.

All that said,
I don't know your confidence level in doing a complete disassemble and clean (which is what I would do).
However if you're not sure or able to do that, then at least remove the shell and give it a good degreasing.
My weapon of choice is CRC QD Contact cleaner #2130 here;
http://www.homedepot.com/p/CRC-QD-11-oz-Contact-Cleaner-02130-6/202262505
Use the red straw and hose it down heavily, blasting all old visible grease and oil off the mechanism then rotate the worm 180 and hose it down again, I use a plastic  container to collect the runoff. Try to get to all those current transfer points the best you can. Also where the axles contact the frames. I do this with the chassis held vertically. If you choose to do this it will require re-lubing of the motor shaft bushings.
I do not see traction tires on either set of driver assemblies, however if yours has them, remove them before degreasing. I do not know the effect the contact cleaner would have on the rubber tires so I always remove them as a precaution. After your sure the mechanism is as clean as you can get it, let it sit overnight (wheels down) to dry before lubricating and re assembly.
Don't use grease where the axles sit into the frame, use conducta-lube here instead.
http://shop.bachmanntrains.com/index.php?main_page=product_info&cPath=879_755_789_828&products_id=3167

Were it my lokie, I would add tender pick-up at the very least, if feasible start with a spectrum all wheels live tender.
I will send you links via PM to another forum I participate on so you can see how I added tender pick-up to a modified N scale tender with lots of pictures. It's a different Bachmann lokie but you will get one idea of how to do this. The procedure is the same just the scale is different.

It's my on going CoG Big Apple project.

[brokenrail]

Have you lubricated the motor bearings recently? The reason I ask is that if you did there is a good chance that when it sits some lube runs into the commutator area of the motor when it sits.Then when you put it on the rail some of the lube gets on the brushes and after a time of running burns off a little to where it no longer hesitates warmed up ,but then when it sits and cools down a little the lube migrates back where it should not be and attracts the crud/brush material worn off.Had a Athearn do that .Ran terrible after sitting a bit.Then after a warm up ran ok.Made some odd sounds ,hesitated and was never quite right until I took the motor out cleaned it and put a new set of brushes in it along with new springs.The old brushes and springs were not worn,but I figured since I had the parts and nothing to lose why not.After that no more noise or hesitation.The cleaning out with alcohol probably really took care of the issue.AFTER Cleaning the old brushes in alcohol I put them in another to test and all was good.
Johnny Adam

[jbrock27]

None of us were born with this knowledge.

This is indisputable.

But this:

Look here;

...is the problem, fewer and fewer people seem to be bothered taking the time to "look" anywhere to attempt to look things up or research them.  Not saying that is the case here. 
Even if it is as simple as going to the Home Page here and looking for parts and loco diagrams.  Rather than take the time to search here or the net, they would just as soon leave it to someone else to take their time to provide info that is often easily obtainable for  themselves.

[jbrock27]

cmsluss, you appear to have had this problem with this locomotive, since February 5, 2013.  I would follow James' subtle hint/advice  and do yourself a favor and replace this with a better model.  It will save everyone the time, including yourself and maybe even save you some aggravation.

[brokenrail]

Some of us are here to help some that cannot help themselves and do it with honor.That is it, otherwise a spectator is the best recommendation.
Johnny Adam

[cmsluss]

Many, many thanks for your evaluation and tips!  Both are greatly appreciated!  Thanks also for the helpful link.  I agree the design of the 0-6-0 lends itself to issues.  I have other locomotives that run flawlessly.  I'm interested in improving this model because it was a gift.  I am grateful for your kindness and. thoughtfulness!

[jbrock27]

I don't see what has changed or been improved since at least February 5, 2013 to now, with the exception of the loco is still problematic

Some of us are here to help...

Count me among them, J.A.  

That is it, otherwise a spectator is the best recommendation.

Have no idea what you are saying here.

...some that cannot help themselves

Sorry, but find it verrrry difficult to believe that most people fit into that category.  Someone who has the use of a computer (notwithstanding those folks that Len personally knows who do not and use public computers) and can find their way here, can also more likely than not, search the Internet for the subjects and answers they are looking for and then after that, seek assistance here.  I am a "teach a man to fish" as opposed to "give a man a fish" kinda guy.  I see more benefits reaped for those that can be taught and are willing to research and learn as opposed those that are just looking to being handed information.  Again, not stating that is the case here.

cmsluss, you are welcome for and am glad you appreciate the tips, even if brokenail does not share the same sentiments.

[James in FL]

@cmsluss,

Posted by: cmsluss    Posted on: Today at 04:58:36 AM
Insert Quote
Many, many thanks for your evaluation and tips!  Both are greatly appreciated!  Thanks also for the helpful link.  I agree the design of the 0-6-0 lends itself to issues.  I have other locomotives that run flawlessly.  I'm interested in improving this model because it was a gift.  I am grateful for your kindness and. thoughtfulness!

You're welcome.


Because this was a gift, all the more sentimental reasons to keep and improve on it.
Again, they are really a simple design and easy to work on.
There really is not a whole lot you can do to this lokie but a few things are possible.
Add all wheels live tender pick-up, this first thing will give you the most improvement, the "most bang for the buck" so to speak.
Without doing the tender upgrade first, anything else you may do will likely have negligible results.

Second would be to replace that motor.
As in my first reply to you;

Your problem maybe there. If you have checked the circuit and not yet found the root cause the last place it could be is here:
If oil has migrated into/onto the commutator, from lubricating the motor bushing, it will hold the carbon dust from normal brush wear.
This oily dust sludge collects in between the commutator plates, eventually bridging them.
When you run the lokie at full speed, the centrifugal force slings this mess out from between the plates, improving motor performance.
Two, three days later the oil has seeped back, starting the cycle all over again.

It is my opinion the motor bearings/bushings have been over lubricated sometime in the past and that this is in fact, the root cause of your rough running issue.
With that being a sealed motor there is really no way to properly clean the commutator and brushes.
You could replace the motor with another from Bachmann, or better yet, give the motorman a call and see what he recommends. Motors are not inexpensive, and you will need to do your own CBA (cost-benefit analysis).

Another improvement that would cost little to nothing, would be to balance the weight over the center drivers.

You will come to a point with this loco, where you will have to decide when to say when.

Motorman here;
http://www.micro-loco-motion.com/home.html

Again, wishing you the best of luck with this lokie.

[jbrock27]

You will come to a point with this loco, where you will have to decide when to say when.

The bottom line.