I strongly advise new collectors of Marklin Z who run their trains to learn proper care and maintenance of their locos, it is fun and the techniques can be learned. Plus very little down time for repairs if you do it yourself and more money for your collection.The beauty of Marklin Z is not only what you see on the track, but also the internal design; they are meant to be quickly and easily taken apart and periodically maintained. And should last for generations.

My tips for cleaning and repair of Marklin Z diesel and electric locos is based on techniques that have been successful for me. Rail buses plus diesel and electric locos with side rods will be discussed during another post.

Train not running and lights not on: Verify that dirty track is not the culprit by running pos/neg wires from your Mini-Club transformer to the wheels (positive runs one side of the loco and negative runs the other side) if nothing happens verify that the whisker wires from the circuit board are in contact with the wires extending from capacitor. Also verify screw is properly engaged to receive electric from the tracks in the case of locos with catenary.

Train not running smoothly on the tracks is likely caused by dirty track. My solution is cleaning track with a lint free rag dampened with rubbing alcohol. Another solution if track is slightly dirty or dusty is to use a micro fiber cloth and/or camel hair brush, my first choice is Leica Camera’s micro fiber cloth which is simply the best and can be cleaned and reused over and over again (available from B&H Photo in NYC). I also have on occasion used a micro vacuum attachment on my Miele vacuum cleaner to remove loose particles of dust. Cleaning track around catenary is tedious and difficult work!

HOS (hardened oil syndrome)- locomotive lights turn on but motor does not turn is likely HOS: Original Marklin Oil eventually hardens in less used locos, this oil hardens to a clay like mass not allowing the gears to move freely, if the motor cannot move the gears if may suffer overheating and burn-out. No way to get around a complete tear down: requires time but it is easy and fun with a bit of enjoyable music. To safely remove the shell without damage I use two guitar picks flexible plastic sized Medium .70mm placed on near front truck on both sides respectively. With very little pressure shell will slide off. The objective to not to damage the shell. Also keep hands clean each step of the way. *Tiny screws and springs get lost easily with this scale, keep a container handy to house these parts, some people I know use a jewelers apron to keep parts together and off floor. GPS97 on Ebay sells a wonderful high density foam work station for $19.95 with free shipping this is a highly recommended item for loco repair. Chassis: 1. using a tiny screwdriver push the silver axle pin out which will release the truck from the chassis. This step will be the first reveal of the hardened oil, the axles may be stuck because of the hardened oil, so a little more pressure than normal to remove those pins  2. unscrew the one or two screws that attach the circuit board to chassis  3. very gently using a very tiny screwdriver work without cracking the circuit board pry the circuit board from retaining clips in each of the four corners 4. very gently bend the capacitor and its wires straight up this will facilitate a much easier deconstruction and reassembly of the rest of the parts  5. Unscrew the slotted screws that hold the two black plastic frameworks to the base of the chassis 6. remove the two drive transmissions notating the how the brass bushings fit into the chassis *note some brass bushings have a flat side and others are completely round, the flat side always faces up and round side always faces down with the bushings that are not round all the way around 7. remove motor and set aside 8. hardened oil happens over time with the particular oil that Marklin used when your loco was manufactured, it is ever present for those pristene locos you are lucky enough to find that were in display collections only and never run. *Note: A loco when it is stored should always be wheels down when stored to help prevent oil from pooling in the gears and housing 9. separate the parts into two groups: group 1- motor with brushes, circuit board and all painted parts (metal chassis) and group 2- all screws, all gears, assembled trucks, axles and plastic frameworks from the top of the chassis that the circuit board sat on. Group 1 set aside until reassembly, whereas place group 2 in a small glass dish with enough “Windex Original (blue color)  to cover, let soak for 10-15 minutes. Note: do not touch Windex and then touch painted parts most notably the shell, although clear lacquer was applied over paint and graphics at the factory Windex more than likely will damage all painted surfaces it comes in contact with: keep Windex away from circuit board, painted chassis (not all are painted), and shell. Original Windex is a very mild solvent that is great at removing old hardened oil but it should not come in contact with Group 1. 10. carefully remove parts from Windex bath and gently dry with Bounty paper towels and let stand for a hour or two giving any of the Windex remaining time to evaporate 11. place trucks on even paper towel surface installing center gear and re-oil with the truck gears with plastic safe synthetic oil recommended for Z scale, Labelle 108, move the trucks back and forth to well distribute the oil 12. reassemble chassis in the order it was disassembled and oiling gear transmissions