Model Specific Issues                                   

On this page, I deal with operational issues (things that make you want to tear your hair out) and corrections that affect the various models excluding motors, which are covered on their own pages. I won't dwell on obvious things like keeping exposed surfaces clean or other normal maintenance issues. Due to nearly identical construction and peculiarities, I am grouping certain models together thus:

E8 and C-Liner

RSC-2, GP40,and SD45

Pacific and Mikado

WDT and 0-6-0

The 0-8-0, 0-4-0 and Cow/Calf have their own sections. I discuss various sub-assemblies in separate sub-sections. Click on a locomotive type to jump to that section.

E8 and C-Liner

Although the most serious problem with these is the motor, there are other things about them that can drive you up the wall (or what I said above).

Frame

Of course, the issue here is Zamac deterioration. Other than causing the frame to get stuck in the carbody, if severe enough, it can cause misalignment between the worm and gears in the power truck. This can result in gear grinding which can range from minor to unbearable. Please see the "Zamac Frame Repair" page for information on how to correct this condition. There is another cause of gear grind which I discuss below.

E8 The two parts that normally don't have to be removed from the frame for normal service are the headlight bulb and socket and the hot contact and plastic mounting plate. The only problem I've ever seen with the headlight bulb or socket is the hot contact in the middle of the end of the socket can lose contact with the tab on the contact plate, either physically or through oxidation of the brass contact on the socket. If it is physically out of contact, pry it out and reposition it further back or bend the plate contact forward so the two are in contact. If it is oxidized, pry it out and polish and reinstall. I don't think I've ever had one of these bulbs burn out!

C-Liner The headlight bulb fits into a hole in the frame and is held by a plastic block/contact. One end of the contact pushes on the middle contact of the bulb and the other end pushes against the hot motor brush holder. About the only problem with this is sometimes the plastic block is too loose a fit in the frame recess and will fall out. I squeeze the corners of the plastic out a little with a needle nose pliers so they stick out more and fit tightly into the recess.

I have seen some hot contact plates having insufficient or no plating on them. The plate should be a nice, shiny silver. However, it still seems to work OK as long as it is kept polished and clean.

Front Truck - E8, Rear Truck - C-Liner

This, of course, is the truck picking up current to operate the motor. There are several areas of frustration with it to be corrected or maintained. With the earliest style truck the wheels are in contact with the axles only by virtue of the inner circumference of the wheel rotating about the axle. This is fine when new because there are six wheels and the chances of current getting through are pretty good. However, once there is dirt buildup and/or oxidation, steady current flow goes out the window and stuttering results, sometimes very severe. The solution to fixing this, of course, is to remove all the wheel/axle sets and clean and polish the surfaces. Unfortunately, these parts are nickel plated brass and the plating eventually wears away with use. Brass oxidizes easily and so cleanings need to be more frequent with an older unit. The surfaces of the wheels contacting the rails will also eventually be exposed brass and may need polishing more often although they will kind of get polished by running too.

Later units have the wheel/axle sets having a coil spring between a shoulder on the axle and recess on the wheel. This improves things a bit since rotation of the wheel tends to keep the surfaces of the spring ends and axle shoulder/wheel recess polished. It's not a cure-all though because dirt will still work its way in there and cause problems. Cleaning is, again, the solution, tediously cleaning each one of those little springs, axles, and wheels. But, we love these things right? So, it's worth it.

Still later engines have the auxiliary contacts mounted to the phenolic plate to pick current up directly from the rail, bypassing the wheels and phenolic plate entirely. This is still not a be-all and end-all since there are only two of the contacts, one for each rail. So, the wheels, axles, and springs (where present) still have to be functional.

The current, after it gets to the axles, is transferred to the copper traces on the phenolic cover plate. If enough oxidation occurs here, it will hinder current flow too. Cleaning and polishing is, again, the answer. The traces on some units are plated and not on others. They will be silver, of course, on plated units. I haven't seen any real evidence as to whether it makes any difference if the traces are plated or not. Don't be too aggresive polishing the traces because they are pretty thin and you may start to remove them rather than just getting them clean. Also, when reinstalling the Phenolic plate, don't overdo tightening the screws as it will warp the plate and some of the axles may lose contact with it.

Next, the current flows from the phenolic plate traces to the two studs into which the bottom plate screws screw. Again, make sure the contact surfaces are clean. Also, make sure the studs are fastened securely. They are swaged over the shiny metal plates on the top of the truck. If one is loose, you can use a fairly shallow pointed punch to re-swage it, supporting the stud on the bottom.

OK, now we have current to the two metal plates at the truck top. Now what happens? Current is transferred to the engine frame by the screw that fastens the truck to the frame and there is a spring under the head of the screw which contacts the metal plate. On the E8s, this is the front plate and on the C-Liners it is the rear plate. You must look for dirt and oxidation here too and clean it up. I have also seen some of the springs used not being "springy" (a spring manufacturing problem). The spring merely gets crushed and won't spring back. This can be verified even without the truck apart by pulling the mounting screw away from the truck. If the spring is good, the screw will be pulled back toward the truck. Of course, if the spring is no good, there will be no reliable electrical connection here.

Finally (lots of contact points in these huh?), the hot side of the current is transferred from the rear metal plate (E8) or front metal plate (C-Liner) to the insulated contact on the frame through a barrel/bullet contact. There are two coil springs involved. One pushes up on the barrel part to keep it in contact with the plate, and the other pushes the "bullet" up to keep it in contact with the frame contact. Fortunately, this assembly rarely ever causes trouble. In fact, even though I know at some time in the past I had this area apart, I can't remember when it was. Disassembly to fix anything here requires the swaged over part of the mounting stud be bent in to allow removal of the plate. Drilling isn't really an option here because there would be no practical way of replacing the stud/swaging for most people. You could possibly drill into the stud and put a threaded stud into it and use a nut to attach the plate, but there isn't much material to work with.

After servicing the truck, it's a good idea to make sure all wheels are contributing to current pickup by using two wires from a power pack and touching one to the front bottom plate screw and the other to each right side wheel and then touching one to the rear screw and the other to each left side wheel. The motor should run in each case.

Rear Truck - E8, Front Truck - C-Liner

Generally trouble-free, there are a few things worth mentioning about these trucks. One is gear grind as mentioned above. I have found that this can be caused by the bottom retainer plate being slightly mispositioned in the front-rear direction, allowing the worm to be too close to one driven gear and too far away from the other. There isn't too much adjustment here because the mounting holes are not slotted, But, you can "bias" the plate one way or the other to try and correct this. I have found that, for some reason, on the E8, there seems to be better mesh if the bottom plate is pushed toward the front of the engine while tightening the screw. On the C-Liner, it's kind of random so if the gears grind, I try to move the plate to different positions to get the quietest performance.

If a truck has helical-cut gears, identified by the gear teeth being at an angle to the axle, they must be reinstalled in the correct position or they won't fit into the truck frame correctly. This is apparent by either the idler gear or its driven gear not bottoming in the slots in the truck. Again, it is best to keep these lying in their correct relative positions when you have the truck apart. In general, it's always best to reinstall these parts back where they came from, even if the gears are straight cut, due to mating surface wear patterns.

If you are servicing a truck with axles insulated on one side only, be sure to get them oriented properly or a short circuit will result. On the E8, this means the traction tires will be on the right side of the locomotive and on the C-Liner, on the left.

Speaking of traction tires, the original Rivarossi tires are vinyl and over time, will generally harden. Test them by using a needle to poke at them. If the needle makes impressions in the tire and the tire seems soft, it's OK. If the tire is hard, traction will be seriously degraded and it should be replaced. The engine may also noisily rumble down the track. I cut my own tires from some silicone tubing I have but I know there are tires available on the market.

There are another couple of causes of traction loss with these locomotives. One is the vinyl tires can slip on the wheels if excess oil or grease is present. The other is the wheels themselves slipping on the insulators and/or the insulators slipping on the axles. The cure for the former, of course, is removing the tires and cleaning the oil or grease off the wheels and tires. If the tires are in good shape and clean and there is still a severe traction loss, check the wheel fit on the insulators and the insulator fit on the axles. The wheels should not turn easily independently of the axles. If there is looseness, use superglue sparingly to reattach the parts together. I do the wheels to the insulators first since this is more common, and then check the insulator/axles.

Some of the truck frames have a tendency to crack down the middle along the mold parting line from tightening the bottom plate screw. On the E8s, it doesn't ever seem to be severe enough to cause problems because the crack is usually only in the vicinity of the screw and nut itself. On the C-Liner, however, I have had to repair some of them due to the truck cracking all along from the front screw to the rear of the truck. I have used two different methods here. Both involve making a small brass plate to span the crack at the rear edge of the truck. I either drill holes and use screws to attach the plate or super glue the plate across the crack. Both methods have worked well. You could try and just super glue the crack itself but it may not hold due to the forces involved.

I will mention here that if you happen to lose the snap ring from one of the early units, all is not lost. A substute can be fashioned from a suitably sized (an 0-80) washer. It needs to have an inner diameter just larger than that of the worm shaft and thickness that will fit. Cut a section out of it so it will insert into the groove at the end of the worm. Then crimp the washer to squeeze it around the groove to retain the truck.

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0-8-0.

There really aren't too many issues with this locomotive not solved by normal routine maintenance (cleaning wheels, wheel wipers, etc.). One area maybe not falling into this catagory is the mounting of the drawbar and contact. If the engine seems to have hesitation problems and all normal things have been taken care of, check here for oxidation and clean it up. Also, make sure the spring contact is positioned correctly so it makes positive contact with the extension of the hot brush holder. It should be well over to one side of the hole in the drawbar and when you insert the extension, force the spring contact over to the other side of the hole so it maintains positive contact with the extension after the extension is in the hole.

Frame

Here again, the issue is Zamac deterioration. If the frame is too far gone to repair as covered on the "Zamac Frame Repair" page, it will have to be replaced.

Drivers and Related Parts

The front set of drivers must be correctly quartered and positioned so the side rods won't disengage from the crankpins. If this happens the locomotive will come to an abrupt halt and the side rods can be bent. In fact, I have one 0-8-0 I got from an auction (it actually was included at no extra cost when I bought a bunch of E8s) that was like brand new except the seller said it wouldn't run. The left side rod had disengaged and was bent. I found the drivers not quartered so when one side was aligned correctly, the other side wasn't. I re-quartered the drivers and straightened the side rod and now it is a great runner.

By the way, quartering is the term used to describe adjusting the two drivers on the axle so when one crankpin (or counterweight) is at, say, the twelve o'clock position, the one on the opposite side is 90 degrees ahead or behind (a quarter of a circle) On the 0-8-0, if the left side driver is at 12 o'clock, the right side driver will be at 3 o'clock facing the right side of the engine. I have found it possible to merely twist a wheel around the axle to get it back into correct position. The fit is usually pretty tight but with a little effort, it can be done.

Other than the above issue, the drive-train on all the Atlas/Rivarossi steam locomotives is pretty robust with the brass gears solidly mounted on the axles (no plastic gear or axle cracking here!). Just think, if the motors were more reliable and if there was no Zamacitis, these would probably run forever! In fact, they are pretty popular for repowering.

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RSC-2, GP40, and SD45

Here we have the three A1G models that can be the epitome of frustration in getting a locomotive to run smoothly and quietly. With patience and proper steps, however, you can be rewarded with a very nice sounding and running engine. Most of the issues involve Mehano's rather sloppy assembly methods and loose tolerances.

Frame

OK, there's no Zamac here so no worry about the frame right? Wrong. I have a feeling that, at least early on, Mehano used lubricants that weren't too plastic compatible. The frame in my U.P. RSC-2 (I think it started to happen to my Burlington GP40 too) developed cracks and became rather brittle in the area of the motor and, in fact, the two detail areas on the sides that represent, I believe, the batttery boxes (they're the two rectangular pieces next to the fuel tank) broke off. I was able to save the frame by scrubbing it with detergent and gluing the cracks and epoxying the two pieces back on. It has been fine for many years now. Needless to say, I completely removed the original oil and grease and relubed with LaBelle plastic-compatible products.

I have also seen some of these frames warp, drooping down at the ends. Fortunately, this pretty much gets corrected when the body is mounted to the frame (make sure it is all the way in by verifying that the ends of the frame are against the body). You could also strip the frame of all parts and use heat judiciously to straighten it back up.

The four little tabs that stick out to engage the slots in the body sometimes grab a lttle too much, making the body difficult to remove. In this case, I trim some of the depth off so they still hold the body on, but not so tenaciously.

The four bosses that insert through the holes in the gear tower cover are very fragile and will break off unless you very gradually work the cover off a little at a time at each corner. If they do break, the cover can be glued in place with a liquid plastic cement and sliced off the next time with a razor blade.

Front Truck

The wheel wipers must be protruding out enough to ensure contact with the wheels at all times but not so much to produce undue friction. Also, adjust them so they are all extended out the same amount so that the pressure on both sides is the same.

Wheel wobble can be an issue here but it doesn't seem to happen as often as with the rear truck and drive wheels. I will address this in the next section.

Rear Truck

The main issue here is to obtain the least amount of friction so the truck is easy for the motor to drive. Adjust the wheel wipers as with the front truck, disassemble the truck, and clean and relube all the gears and axles (I use LaBelle 106 with Teflon). After the truck is reassembled, turn the wheels by hand to check for free movement of all the parts. Temporarily install the worm gear with the retaining pin to include it in the test. Place the truck on a piece of track and push it. It should move fairly easily and the wheels should turn instead of skidding along the track.

Wheel wobble is common with these locomotives and it is generally thought to be caused by the traction tires. However, I have found that there are actually three possibilities for this. There are the tires themselves, the holes in some of the wheels may be drilled off center, and the axle ends where the wheels mount may not be concentric with the rest of the axle. In fact, the last two reasons are a more likely cause than out-of-round tires.

Of course, the cure for bad tires is replacement.

If a wheel has an off center hole, it can be corrected by mounting the wheel on a steel rod so there is an interference fit. Mount the rod in a lathe and make cuts around the outside of the wheel to true it back up. Cut only within the tire groove (I made a custom cutter for this)and cut just enough off the high spot so the wheel is concentric with the hole and no more. This reduces the effective diameter of the wheel somewhat but I have found it doesn't really affect the operation once the tires are put back on.

If an axle end is not concentric with the rest of the axle, you can file or sand the side that is too far toward the outside to true the axle back up. Of course, after doing this, the wheel may not fit snugly on the axle anymore. I just use a bit of superglue to secure it. The ideal solution here would be to replace the axle with a good one.

Drive Train

Here is the main source of noise and rough running. The motor itself may be noisy because of loose bushings or uneven spacing between the armature and pole pieces (see "The Mehanotehnika Motor" page), the mesh between the worm and worm gear may not be correct, the alignment between the parts of the coupling between the motor shaft and worm shaft may not be correct, or the worm bushings may be a sloppy fit in the frame recesses.

Assuming that the motor noise has been reduced to an acceptable level, the next place to look is the worm and it's bushings. The bushings fit into two recesses (grooves) molded into the frame. The fit should be fairly snug in the frame so that they can't bounce around and cause vibration. If they are loose the result is a kind of hashy, "vibraty" sound that can be very loud, especially at higher speeds. You can use shims beside the bushings or gently squeeze on the sides of the recesses to make them narrower. The shim method is safer because the plastic can break, of course.

Supposedly, when the bushings are bottomed in the recesses, the worm and worm gear mesh should be correct. This is not always the case. A rough, grinding sound as the loco moves down the track is almost certainly caused by the mesh being too tight. In the past, I have trimmed off the teeth on the worm gear but I have also found there sometimes is enough clearance between the top plate on the gear tower and the top of the bushings to move them up slightly to correct the mesh. You can put shims under the bushings but sometimes, if the bushing fit is snug enough, you can get away with merely moving the front one up a little by prying on the shaft and it will stay in place.

Look to see that the alignment between the pieces of the coupling (either the male-female halves on the one type, or the two ends and rubber piece on the other type) is in as straight a line as possible. The motor may have to be biased to one side or the other to get horizontal alignment. Make sure you check everything with the frame straight and not bowed as may be the case with a warped frame. Bend it into correct position to see how the parts align as that is how they will be when the chassis is installed into the body. Make sure there is enough clearance between the parts so they won't jam together front to back when the locomotive is assembled.

With all the above being said, this whole thing of getting these locomotives to run quietly can be a time consuming and frustrating exercise to hit on the correct solution. It is a trial and error thing. However, you will definitely know when you get it right. The loco will move with a pleasant, kind of whirring sound as it moves and the noise will not get obnoxious as speed is increased. Some of them have a subdued whine to them as if there actually is a miniature turbo-charger in them. Also, they crawl at low speeds almost as well as modern locomotives.

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Pacific and Mikado

These two locomotives, like the 0-8-0, actually have few operating issues outside the motor and frame problems. I separated them, however, because there are a couple. Of course, if you have trouble with the siderods disengaging from the two front driver crankpins, check the quartering as on the 0-8-0.

Also, as with the 0-8-0, be sure the spring wire contact on the drawbar between the tender and locomotive is clean and in the correct position. It must be over to one side of the hole for the lower brush holder extension so that when the extension is inserted into the hole, the spring contact is forced over and will maintain positive contact with the brush holder extension.

Another frame related issue is the boiler shell not nesting all the way into the yoke (in between the two cylinders) at the front of the locomotive. This affects the Pacific and Mikado and not the 0-8-0 because these two engines have a separate brass threaded combination nut/screw at the top of the frame into which the boiler attaching screw inserts. This nut/screw also holds the worm housing in place in the frame. It is possible for this piece to hold the shell in such a way that the front is raised up from a normal position. The way I fix this is to first make sure it is screwed in all the way. Now, mark the nut with a scribe across the center from one side of the loco to the other and mark the front half. Remove the nut and file the front half at an angle so that there is a slope down towards the front of the locomotive. Reinstall the nut and the sloped side should be at the front. This slope will allow the shell to settle down toward the front and seat into the yoke. It may take a few tries to get enough material removed from the nut.

I have heard, more than experienced myself, that there can be a problem with pilot truck derailment. On both models, there is a downward force imparted by a coil spring upon the truck to keep the wheels in contact with the rails. Of course, you want to check that this spring is present and hasn't lost tension. Some have mentioned mounting addtional weight to the top of the truck but I feel that if the spring set-up is functioning properly, this shouldn't be necessary.

If the headlight doesn't work in either of these models and the bulb has been confirmed to be OK, the contacts are probably mispositioned. Bend the ground (pacific only) and hot contacts out and up more toward the top and front of the locomotive to correct.

Finally, there is an issue with the coupling between the motor shaft and worm shaft. I have found that, due to the construction and characteristics of this coupling, it can create side forces on the bushings which can lead to vibration and resulting noise. The coupling looks to be designed so that there doesn't have to be perfect alignment between the two shafts (the wedge shaped ends of the plastic pieces). However, I believe that because of this, if there isn't perfect alignment, vibration can occur from one piece trying to "slide" on the other. I have replaced these parts on some of my Pacifics with silicone tubing and it has made a great difference in the noise of these units. There really should only be some motor and gear noise and any "hashyness" or vibration noise is not normal.

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WDT and 0-6-0

Not too many issues here either other than the rear motor bushing problem (see "The Mehanotehnika Motor" page) or "Zamacitis" (see "Zamac Frame Repair" page).

Of course, wheel wobble can be a problem with these and the fix is the same as for the other Mehano locos (RSC-2, GP40, SD45) although there are no traction tires present. Most of it seems to be the axle problem rather than wheel holes being drilled off center but the latter is a real possibility too. Also, remember that the axles are fairly fragile and will break if uneven or too much force is applied to them.

As I mentioned in the section for the WDT on the disassembly page, the front of the plastic wheel wiper mounting plate has a tendency to bend up from the pressure of the wipers and although it won't usually cause any problem as long as the wipers stay in contact with the wheels, it bugged me. So, I drilled a hole through the plate at front center under the headlight bulb and drilled and tapped a hole in the frame for a small screw to secure the front of the plate. The 0-6-0 already has a screw in this location.

One thing I have done to the 0-6-0s is to trim a little off the side tabs that engage the slots in the boiler/cab molding to make it easier to get the boiler/cab off.

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0-4-0

Since this is a Rivarossi locomotive, the potential motor problems can occur here too although Rivarossi had addressed the commutator problem by the time of the release of the 0-4-0 and beefed it up. In fact, by this point, the Rivarossi can motor had become quite reliable.

Although it appears that the boiler/cab shell is a Zamac casting, I have never seen any with "Zamacitis". Anybody else?

Since there are quite a few contact points for current conduction on this lcomotive, it is essential that they all be inspected if there is an intermittancy problem. These include:

1. Tender wheel wipers.

2. Drawbar contact points (upper and lower).

3. Driver retainer plate to lower brush holder contact.

4. Lower brush holder contact to lower brush holder.

5. The small contacts on the driver frame. The left contact wipes against the left drivers and the two small upturned tabs contact the boiler casting. The right contact wipes against the right drivers and the two small downturned tabs contact the driver retainer plate.

6. Upper brush holder contact to the boiler casting.

All of these, of course, must be clean and in reliable contact for the locomotive to run smoothly.

Potentially, the most troublesome are the two small wheel wiper contacts mounted on the plastic driver frame. They are fairly fragile and the wheel wipers can be easily bent. Looking up from the bottom of the loco, check to be sure that the wipers all stay in contact with the driver flanges as the drivers are moved back and forth.

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Cow and Calf

There aren't really any particular trouble spots with these locos other than the kind of a pain it is to disassemble/remove the trucks during loco disassembly. I suppose the wheel wipers are potentially trouble just like any wheel wipers but there are relatively few contact points in this locomotive. Rivarossi had their can motor refined by the time these were manufactured and, so, that is not really an issue with these as with the earlier Rivarossi locomotives.

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Please contact me with additions or corrections: dgosha@aol.com

Pick a page to go to:  

EMD E8s FM C-Liners IHB 0-8-0s
Alco RSC-2s EMD GP40s USRA Pacifics (4-6-2s)
Plymouth WDT Diesels 0-6-0 Steam Locos EMD SD45s
USRA Mikados (2-8-2s) 0-4-0 Locos and Tenders SW1500 Cows and Calfs
Atlas Locomotive Disassembly The Rivarossi Motor The Mehanotehnika Motor
Zamac Frame Repair Atlas locomotive Reassembly AIG Locomotives Around the World
The Treble-O-Lectric Main Page Treble-O-Lectric Locomotive Service Treble-O-Lectric Documents
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