First, have you looked at the working and not working one from underneath (remove the plate that covers the mechanism first)?

As far as I recall it, there is a spring that is part of the transmission of the action of the solenoid to the turnout itself and if that is missing, it will of course not work. You can also check if there is rust preventing it from moving.

If the turnouts pass this test, then:

Second, connect ideally an Amps-meter in series with the solenoid or if you don't have an Amps-meter, a lamp (e.g. one for lighting H0-buildings). In this way you can see if there is a current passing through the solenoid or not.

A simple drawing:


If this test fails, then you have found the solenoid faulty and then there are a few options:
1) Check the soldering of the yellow and blue wires to the solenoid
2) Dismantle the solenoid and check the thin copper coloured wire and finally if OK re-wind the coils of the solenoid.
3) Get a new spare part (or turnout)

Thank you both for these ideas. I've compared a working with a non-working unit and can find no visible difference. The spring is in place on both and both operate freely when the lantern casing is turned by hand. There is a circuit through both of the solenoids (they seem to be in two parts with a blue wire connected to each end and yellow wires soldered together at a centre terminal). The rails move freely as do all the visible working parts. There is no sound coming from them but one of the non-working ones started to smoke! That, I think, must be a rusted solenoid and beyond repair.

Any other thoughts much appreciated.

Regards, and thanks

Chris

Hello Chris,

My new layout haS 30 M track turnouts including many from E bay. I found that many would not work everytime when operated by decoders. ( I install first and test later ) Some including both double slip decoderes would not work at all. I changed to push button control using Viessmann 5547 panels and all work every time. It's also much less expensive.

good luck,

Tex

Hi Chris,

I notice that you refer to a circuit board underneath, and one of them being from a digital starter set. They haven't had decoders installed in them have they? Marklin used to make a decoder for installation on the underside of M track points. If they have then they need to be wired for digital.
Any chance of a photo of the underside?

Cheers....

Mike.

Chris,

this is getting to be interesting. Is the photo from a curved turnout ? I had two of them in my origional Marklin 2602 starter set but never opened them. They worked with the digital control unit that came with the starter set on buttons 3 and 4, however they never operated when I upgraded to a 6021 control unit many years ago. The only way to operate them would have been to install a switchboard with the correct address.

Tex

Not knowing what your plans are. Would you operate the turnouts in digital or analogue mode?

In case of digital mode, as pointed out earlier, perhaps somebody has the operations manual.

In case of analogue mode, then it would be relatively simple to turn them into analogue. Just cut the yellow, green and red wires going from the decoder and extend them with longer yellow and blue wires (connected to the green and red). Solder the joints and put shrink tube on them. You could also put shrink tube around all 3 cables and use the hole above the decoder as "cable duct".

Doing this modification of course assumes the solenoid works ok and this could easily be tested before doing any cutting or soldering work by twisting test cables around the soldering points of the solenoid and then use the method I described earlier.

(If you leave a short bit of each of the coloured cables soldered to the decoder would simplify restoring the turnout as digital, assuming the decoder is OK).

Turning the turnout into analogue this way would of course also make it possible to use external decoders in digital mode. This would in particular apply if the smoke mentioned earlier came from a decoder.

Chris,
In addition to the excellent advise many have offered you above, let me tell you that I have had very bad luck with old M turnouts (see my postings in "Me and My Layout" page, https://www.marklin-user...lding-my-new-layout.aspx ).
My problem was not the operation of the solenoids (they worked perfectly), but the aged spring that moved the old frog legs. No matter what I have tried I could not get 100% reliability from them for my operation. So, I solved the problem by replacing the M turnouts with C. I had to do some "re-engineering" on the C turnouts so they could be connected to M track, but the result was perfect.
Should you decide to take this solution, contact me and I'll explain in detail how to make the connections to C-to-M.
Regards,
Yannis

I always replace the springs on all of my m-track turnouts before laying the track.. I think that the part number is 35308 (or it could be 765530).. The other thing is to ensure that the tracks are not twisted - they must always we laid flat on a layout with the nearest approach tracks also laid flat...