Firstly, it looks like this:


Image borrowed from https://swissbahn.ch

This loco has a clicking sound at medium to high speeds. The frequency of the sound changes with the running direction. Initially, I thought that I had solved the problem when I found that one of the plastic clips that holds the motor down was broken. After waiting for many months for two replacements, the noise is still there.

The motor was removed and the remained of the loco pushed along the local dealer's smooth C-track (I use M-track, but it can be hard to use for this sort of diagnosis). You can feel the click and it seems to be in the running gear, but there is nothing obviously wrong. By chance, another one arrived at the dealer's place and, it too, has a clicking sound that is slightly different in frequency.

Has anyone else experienced and fixed this problem?

Hmm.. Good thought, but how do I set them up correctly?

If you remove the coupling rods from both sides, do you still get the noise?

Please describe "feel the click"

Was the same pushing force needed all the time, or could you feel any spots - related to
wheel rotation - where it got just the slightest harder to push it?

I think I would remove both motor and slider, and then try again, really slowly pushing,
using only one finger, to see if the are any "hard" spots on a wheel rotation.

And then remove the coupling rods, and try again if pushing feels the same

Per.

I concur that the coupling rods are likely the source of the clicking. My guess is that one of the rods may be rubbing against the other part as the locomotive moves, causing a clicking noise and a slight tick that can be felt. To check this, use a Lokliege or test bench to test the locomotive while it is inverted and observe the rods as they move.

Regards

Mike C

I would remove one of the bolts securing the rods. Then run the loco to see if the clicking stops. if it doesn't, replace that bolt, then take the same bolt out of the other side (unless you can identify the side that clicks) and try again. Keep working you way around the bolts one at a time until the clicking stops.

You may also want to see if there are two clicks per wheel rotation, as both sides could produce a click but it not be obvious. You may need to run the loco very slowly to pick this this up.

I managed to get back to this problem today. It got worse and the same problem appeared in a second identical model after a short running time.



The gear is split. At first it is a small crack, which widens with the torque applied to the gears in one direction. After a while, it widens to this gap you see in the image above. When this happens, the sound happens in both directions and you can actually feel it by rolling the chassis along the track after you have removed the motor. You can't see the crack looking down the wheel from under the loco, you need to look from the gear side - very hard to see.

My theory is that there is a slight imbalance between the gear driven by the motor on the other and the wheel pushed by the rod from the other geared axle (the one with the tyres), which causes stress at the gear leading to the crack (and very slight click) that grown into a large gap and a much louder click.

Needless to say, it looks like the part is no longer available. Both 36331s are now dead.

A potential solution is to remove the idler gear that runs off the axle with the broken gear so that that axle is driven by the rod from the other axle (with the tyres) and not by the motor.

There are a number of parts which are not available as spares, but the item may still be available for factory repairs.
I would try emailing Maerklin and also try one of the Swiss service people to see if they have this in stock.
https://www.maerklin.ch/...service/reparaturservice

Regards

Mike C

That is nasty. It looks like the hole is the gear has been made a too tight fit on the axle, with the result the gear could not withstand the stress.

I wonder if the gear is a separate part to the wheel, in which case a spare part for a later model, and access to a wheel press would be the way to fix it. But I would also carefully measure the hole and axle diameters and talk to someone with experience of interference fits in metals to see if they are appropriate.

Keep us posted- I'm staring nervously at a few locos in the display case...

That would be a quick explanation. (and the seetal parts are n longer available either, so it kind of adds up)