Hi,

I'm new here and have a question.

I tried the search function, but nothing was found even with very few search terms, so I'll posy my question instead.

I bought a Primex Set 2753 with V200 Diesel Locomotive, 3 Wagons, Track Oval & Transformer Controller (probably made in the 1980's) and the locomotive is now broken.

It used to run, but would start to make intermittent loud screeching noises at times, apparently whenever the motor got more than a little warm after maybe 10 minutes of running.

The locomotive also seemed to run slower than expected, with particularly a lack of acceleration beyond the medium speed range.

Oiling the motor and gears with Ballistol did not fix the problem.

Yesterday the locomotive suddenly did not work any more after standing for a few hours off the track. It was working when I took it off the track earlier on.

The locomotive makes a buzzing sound and the lights come on when voltage is applied, but it wil not start to move at all.

The wheels cannot be turned by hand any more, the rotor appears to be stuck but it can be turned with difficulty by inserting a tool into the rotor and pushing it round.

It appears to me that some sort of bearing has failed, but I'm just guessing.

How should I go about fixing this?

Can I soak the engine in diesel, mineral turps and/or methylated spirits to wash out any possible gunk or foreign bodies, or would this destroy parts of the engine/gearbox/electronics?

Thank you very much for any help with this, Mik

Yikes, no, not sewing machine oil - it's too light (at least the stuff we get here is). If you can get some Labelle 102 or 103, that's great, if not some folks in our Marklin club use clean 30/40 engine oil and swear by it!

Isopropyl alcohol is also good for cleaning motors - it doesn't leave any residue.

Thank you everyone for your advice, much appreciated!

The engine is running again, much better than before it ceased up.

I took it apart and tried to wash off the black mess inside of it with methylated spirits, but it did not not work too well. The mixture of oils and dust and soot did not dissolve easily in the alcohol. Much rubbing with tissues and ear cleaners was required.

What worked much better was to add further Ballistol to dissolve the gunk, then again soak the parts in methylated spirits. The amount of dirt that came out of the gear box (after it had already been rinsed in methylated spirits twice, and rubbed with cotton buds and tissues) using this approach was impressive.

I'd like to show some photos, but have not yet been able to work out how to do this on this forum. Let me know how, please!

Here is what I think happened: The Ballistol loosened up the gunk that had built up over the decades, turning it into something akin to engine grease. Then, when I added even more Ballistol, the gunk liquified enough to free up the parts until a tab got bent into the rotating path of the rotor.
Ballistol is actually designed to do this, i.e. to dissolve baked on residues until you can wipe them off.

There are 2 small copper tounges that are inserted (from the side of the armature (?? not sure what to call it) that holds the brushes) into the motor, and then they get bent flat against the inner housing of the motor. One of these tabs had somehow been straightened out again, thus interfering with the rotor's movement.
When all the gunk was cold, then the rotor could not touch the protruding copper toung, but once heating of the gunk made it softer, the rotor began to occasionally rub against the protruding copper tounge. This caused the intermittent loud screeching noise, which was accompanied by sudden deceleration of the engine. When I added even more Ballistol, things got so loose that the rotor eventually hit the protruding copper so hard that it got bent into the path of the rotor, making further rotation impossible.

Once I've figured out how to integrate photos, you'll see what I mean.

Thanks again, Mik

ps: Photos now attached, but how do you integrate them into the text and maybe explain what each photo shows if needed?