My BR78 (H0) short circuits at al my non electric rail crossings.

Then the Intellibox runs into short circuit mode (safe) and shuts down the power. Then i need to replace the BR78.

It happened mostly when running on slow speeds (<70%).

I personally think that the wheel flens or cog-wheels hits the 3rd rail and creates this short circuit.

But i'm not certain.

Does anyone have the same problem and knows what causes this problem?
And how to solve this problem.

Thanx anyway!

I use the M24640 crossing and also the M24649.

But the problem with the M24649 is less then with the M24640.

The problem occur in all the directions.

The BR78 is the only loc. that have this problem.
The other 5 locs run just fine over the crossings.
Also at very slow speeds.

My locs (E44, E103, V200, V360, BR78, BR85 and also the E194(which is in repair)).

The problem has been detected: the Cogwheels are the problem.

After checking al the other possible causes.
I did the following:

Before the discovery i first isolate the stud around.
That means i put some isolation around it but leave the top clear so the contact sled can keep connected with the power rail. After this isolation step the problem still occur.

So the second thing a did is isolating the tops of the studs. And voila the problem is solved. For the isolation i use some painters-tape. And exactly at the location of the stud at the side of the loc where the cog-wheels are i see a clear black spot of oil from the cog-wheels.

But the next question is: did Marklin made a mistake whith the design of this loc at this particular point. Or is this just one of a million problem that only i have #;)

Hello,

I will isolated the studs around (also the topsection). That works just fine. And when i get trouble with real damage of the isolation rubber in a short time, because of train passages, i still can cut-off the top of the studs.

Thanx.