Repairs

Control Panel Removal and Replacement

The control panel contains no user replaceable items or adjustments and is normally never necessary to access. In the event that the troubleshooting guide indicated the need for service you will need to remove the control panel. This panel is fully connectorized and may be removed for repair or return to the factory.

To remove the control panel remove the cab roof, unplug and remove the battery and its cable, and remove any keys in the switches. Using a 1/8" hex bit, remove the two screws shown in the drawing. Tilt the control panel rearward being careful to not damage the paint. Unlatch and unplug the black colored connector going to the motor (it unplugs in the same way as the battery cable but is a smaller connector). Unplug all other white connectors by pulling them directly apart. Do not twist or rock the connectors or damage may result. Remove the panel from the cab.

Replacement follows the steps above in reverse order.

Fuse Replacement

The fuses may be removed by pulling directly upwards, out of the connector in the panel. Test fuses with an ohmmeter or other conductance tester, or by replacing with a known good fuse. Replacement fuses are available from automotive supply stores. Use only a fuse of the same ampere rating as a replacement. Never increase the fuse rating; repeated blowing indicates a problem that must be corrected.

Headlight Bulb Replacement

To replace the headlight bulb first loosen the two screws on each side of the main headlight body (see drawing). Do not loosen the screws inside of the cab.

When unscrewing the two screws use a 1/16" hex bit. It is not necessary to remove the screws form the headlight body but it will not do any harm if they are removed. As the screws are loosened you will feel the headlight body unlatch from the base. Be sure to hold it so that it cannot fall. Pull the body away from the base and remove the bulb from the body. The bulb may be unplugged from its socket by pulling it directly outward. Use care to not pull on the wire leads or to break the bulb.

Inspect the socket and the o-ring seal at the front of the headlight body and replace if necessary. Replace the bulb and reassemble in reverse order of disassembly.

Belt Replacement

Replace the belt when it is worn out or damaged. Worn out is defined as so narrow that it runs against the bottom of the pulley instead of the sides (and will slip even if tensioned). Be sure to note which way the belt runs around the pulleys. The belt that leaves the left side of the locomotives motor pulley runs below the front axle. The drawing shows proper routing.

Remove the guard as explained in the prior section. Loosen the motor mount bolts and move the motor mounting plate towards the jackshaft. Remove the belt from the motor pulley. It is easiest to detach or attach the belt links if the belt is turned inside out (so that the inner surface faces outward). You will note that the belt has small "T" shaped tabs sticking through its inner surface. Turn one of these one-quarter turn (you may use smooth jaw pliers if necessary) so that it will go through the slot in the links below it. With this one tab detached, turn the belt one-quarter turn at the link next to the detached one so that it separates at that point. Remove the belt.

Install a new belt using the reverse of these steps. Tension as discussed in the prior section. Be sure to check the tension of a new belt after approximately 2 hours and 10 hours, as it will change during its initial operation.

Chain Replacement

To check the chain remove the guard as discussed in a previous section. When a chain wears it becomes longer and its looseness will be noticed in operation. If the change in length is equal to one link or more the chain should be replaced. A chain that is broken, significantly longer than the other chain, unusually stiff, or rusted should also be replaced. Unless the other chain is almost new it is generally better to replace both chains at the same time.

The chain may be replaced with the correct length of #35 roller chain and connecting link. Be sure to replace the guard when finished. A small amount of oil may be applied to the chain but excess amounts will attract dirt.

Uneven Amount of Movement Needed Before Movement in Forward versus Reverse

It is normal for there to be a small difference in how far you must turn the speed control knob to begin movement in a forward direction versus a reverse direction (either may be larger). When running on the track under load this is probably not something you will notice since when movement starts depends on many factors; uphill versus downhill, differences in rolling resistance by direction, curves in track, etc.

If the difference is large enough to bother you it may be corrected by an adjustment detailed in the steps that follow. Please realize that you must be very careful while making this adjustment since it requires opening of the hand control. Do not allow the internal parts of the control to touch any metal objects, make sure you are not in an area where you can accumulate a static electric charge (such as on a carpet), use the proper tools, do not force anything, and if you are uncertain stop and get help.

This should be done in a quiet and safe area

• Securely block the locomotive up so that the wheels are free to turn. Be very careful to make sure that the support will hold the weight of the locomotive and that it will not allow it to move.
• Install and connect the battery, connect the hand control, turn on the master switch and circuit breaker and make sure the locomotive operates
• Remove the six screws that hold the back of the hand control on using a Phillips screwdriver
• Notice how the cable enters the hand control and how the back is assembled then carefully lift the back away from the front
• Using the drawing showing the entire hand control, locate the pulse generator board
• Using the detailed drawing locate the centering control adjustment screw on the pulse generator. This screw turns but does not move up or down, you make the adjustment by turning it with a very small screwdriver
• With the speed control knob in the off position gradually turn it to the slowest forward running position, you may hear silence, a humming sound, or movement of the wheels
• If you hear silence, turn the knob to a faster position until you start to hear a hum, note how far you must turn the knob to get this amount of hum
• Repeat the two steps above for the reverse direction
• If the amount of movement of the speed control knob is significantly different for forward and reverse you may adjust the centering control to make the two more equal. Turn the adjustment only a small amount. If you find the difference is getting larger you are turning the adjustment in the wrong direction. Then repeat the three steps above. Turn more or in the other direction until you are close to having them the same (perfection is not possible)
• Make sure the cable is in the notch at the top of the hand control and reinstall the back cover – Do not over tighten the screws

If the error seems unusually large, such as actually starting in the wrong direction, you should make this adjustment as soon as possible. If the adjustment required is very large you may want to do a complete recalibration as discussed in the next section.

Pulse Generator Calibration

To do a complete calibration of the pulse generator requires the use of an oscilloscope. If you have access to this equipment use the procedure that follows. If you do not want to make an adjustment under these conditions you may return the hand held control unit (only) to the factory for recalibration. If the locomotive is under warranty this will be done at no charge (you pay shipping to us). In other cases please enclose $20.00 US or provide a credit card number to pay for the service and return shipping costs. Note that this will return the control to original specifications and may not provide perfectly even movement amounts, as would calibration to your locomotive using the steps given above.

Use the information above to locate the centering and range adjustments. With the hand control connected to an operational locomotive and its back removed connect the oscilloscope probe to the yellow wire that runs from the pulser board to the speed control. Connect the ground of the oscilloscope to the battery negative lead. Set the oscilloscope to display the pulse width on a scale of 1 or 0.5 ms per division.

• With the speed control set in the off detent, adjust the centering control to produce a pulse width of exactly 1.5ms.
• Turn the speed control to full reverse (counterclockwise) and adjust the range control to produce a pulse width of slightly less than 2.0ms.
• These two adjustments interact slightly so repeat the steps above until a constant range is obtained
• Check to see that the pulse is approximately 1.0ms at full forward.
• This completes the procedure. You may still want to make slight adjustments from the values set in this step to exactly match your system by using the procedure in the prior section.

Paint Touch-Up

Touch up paint is available as listed in the parts list. Small chips can be filled in using a small brush. To match the surface finish of the locomotive on larger areas requires spraying. Be sure to clean the surface before applying the paint. Clean up your equipment using lacquer thinner after painting.