I our shop finally got our ten wheelers in stock. I brought mine and a couple others for customers home for testing. All run great except for one which exhibits the chug noise some are noting and the pilot truck derails. I started with the pilot truck derail problem first. Below is an illustration of why it is happening.. Adding weight will not solve this problem, it is mechanical and the tollerances are so close that it should only take a swipe or two of a file to fix. Because of the tight tollerances and the variablility of the mass production, I can see why this is a hit or miss problem. There is not enough verticle play in the dark blue connecting bar in the drawing. The back of the pilot truck pushes up on the bar, angling it upward and pulling the front of the pilot truck off of the rail. I have tried loosening the screw that attaches the pilot truck to the bar and it did not help. My next fix is to file a little thickness off of the top of the pilot truck connecting bar. Because the pilot is so close to the lead driver, it doesn't take very much verticle missallignment at all to cause this to happen. A few thousandths difference in thickness from one loco to the next could be the difference between one loco being perfectly fine, and another causing problems. My second loco is perfect and shows no tendancy at all to derail at the same point, or any other for that matter, including a yard ladder built of Kato #6's. More to come as I devise a fix.
A very informative post with diagram. Thank you. I wonder how many people other than me have experienced the effect without knowing the actual cause.
After fixing the pilot it should look like this.... After fixing that and running the loco for a while, I discovered the clicking problem. Again, it is combination of tollerances that adds up to cause the issue. The front traction tired driver is not pinned to the side rods. The rod simply hovers over the driver, giving the illusion that it is attached. This is a somewhat normal practice, because it makes it easier to repair/replace the traction tired driver. From the etching process it looks like the main side rods can have a slight bow outward. This allows the rod to tick on the crosshead guides. A slight flex so that the ends are bowed inward seems to solve the click.
More info on the clicking.... Did run into one other issue though, keep an eye on the crank pins on the right side of the loco. The drivers on this loco have cast metal centers so they couldn't use push pins for the crank pins. They are very small hex bolts and one was working loose. A little locktite solved the issue. The people that are complaining of the clicking/ticking may have a crank pin unscrewing itself and allowing the side rod to flop/click around, also causing inconsistant drive to the rear driver which could also be the hitch in the getalong. After locktiting and tightening the screw, the loco is quieter and smoother. Probably ought to do both of them but the right side want's to unscrew itself relative to the rotation of the drivers. BTW - the side rods to not ride on the screw, there is a bushing molded into the driver, the screw head simply captures the rod on the bushing.
Thank you, Tony, for the information. Good to know the problems in advance and how to solve them. My engine is either somewhere at customs processing or still in "my bin" in Albuquerque.
Out of 3 loco's I have on hand to play with, only one presented any issues. If your loco runs fine, don't mess with it. These are easy cures for the problems some have been reporting to save yourself the time and trouble of sending it back to Bachmann. So far, the things I have found have all be simple fixes. Nothing that should be above anybody on this board to repair should you need to.
Tony? Are the 2 drawings on the bottom reversed? The top drawing shows a thinner bar but says it is 'stock form'. The bottom looks thicker but says it is the modified (filed) one. Or am I just not thinking clear. :tb-biggrin: ** OK...disregard...I see what ya did now ! Told ya I wasnt thinking clear...LMAO ** .
I flipped my front trucks with the painted side up and the grey side down and I haven't had any issues. If you look at the exploded diagram that comes with the loco it shows the triangle design on the side of the front pilot wheels vertext point up. So I tried it, flipped it, the screw fit better and it has tracked just fine. I think it might have been a messup in installation from the factory. The grey side is facing the trackes but who is going to see that? Check it out guys, I think it is a quick easy fix.
JoeS - That is it. Thanks for posting that. Joe is right, the pilot trucks are installed upside down. When flipped properly, the spring detail matches the prototype and a lot more verticle clearance is gained. I edited my original photo to reflect Joe's suggestion. It may cause a little confusion in the reply's but it should keep someone from modifying things that they don't need to if they don't read the whole topic.
Checked both of my locos for loose pins on both sides of the last driver. Found that both were very slightly loose so a quick visit to the hardware store for some locktight will fix that. Will flip the pony truck tomorrow and retest on that 7 and 5/8ths switch. May have been why it didn't navigate them while it did the number 6s. With the relatively short wheelbase they should be able to take some fairly tight radius.
I have broken this model in at my track after continueous running for 5 hours, and thought that would solve the problem of my 4-6-0 that binds when running forward and making humming noise. The loco would quit running until I let it run reverse for a while and then forward again. Do you guys know if there is a easy fix for this, I tried unscrew the plate that holds the drivers in place and see if there is any obstruction, but I couldn't find any.
Bachmann's have a lot of play in the siderides. It sounds as though the rods may be hanging up on one another. Drop power, leave it where it sits locked up. Note where it occured on the layout, visually inspect the location of the wheel position, and inspect the siderods. If you figure out that it's binding on the siderods you probably just need to tweak it a tidbit. The S.
Ran mine alot last night. It no longer derails, but in my exhuberance, I introduced a new problem. Bending the faux drive rod emiminated the clicking on straights. I'm running a small R11 Unitrak loop and the clicking was still happening on turns. I made a slight adjustment to the hanger arms, thinking the crank was catching. Now my nose goes back and forth like Thomas the train is shaking his head No.... My hex bolts seem tight, whats a good small wrench set? For something that small, I'm thinking It needs very sharp edges.
I replaced the photo with instructions on how to modify the pilot draw bar with instructions to flip the pilot. Just making sure someone doesn't do any extra work that isn't needed.
The shaking on mine was a popped hanger arm. Went back on fine, It's pretty good on straights now, but it does click on 11"radius curves. Hopoing for better, but we will see. I really cant find good wrenches small enough for these hex bolts. Any leads.
Here is mine as it stands now. Replaced the tender with a USRA Short. Replaced the headlight LED with a pure white one. Installed a DN135 decoder in place of the factory light board/decoder. Opened up the roof hatch. Installed working McHenry coupler on the front. I still need to replace the dummy Bachmann coupler on the tender, decide on the best number for the loco, and weather it. After fine tuning the mechanism this little thing will crawl a tie at a time and runs dead smooth. No hitch, no hunting. As much as a pain it was to find the little things that were wrong in the assembly, the result is and incredible little loco. For those of you finding a clicking, I found and solved one in mine after handling it repeatedly when I was working on it. Make sure the cross head guides are angled outward, away from the cylinders slighlty. Even better if the bottom guide sets out a touch farther than the upper guide. The Crosshead was hitting on the verticle link attached to it and causing the click. Tweaking the cross head guides cured the sound and click. Also cured the minor hitch so I think that may be the issue for many people out there.
