What would you use to clean the gears of an old trolleybus?

[railaddict]

I hope I'm in the right place to ask my question.

I have gone through the german companies I knew in the time, like Herkat and Lux but they have only material to clean the track. I have found an old Ehem trolley and the gears are full of hair, dust, grime.
I was thinking of something like a spray that would dissolve all that dirt, without damaging the gears. Does it exist or maybe you use someting else.

 

[ebay mike]

I hope I'm in the right place to ask my question.

I have gone through the german companies I knew in the time, like Herkat and Lux but they have only material to clean the track. I have found an old Ehem trolley and the gears are full of hair, dust, grime.
I was thinking of something like a spray that would dissolve all that dirt, without damaging the gears. Does it exist or maybe you use someting else.

I've used carburettor spray cleaner in the past on some N gauge locos. It doesn't affect any plastic or rubber parts on my motorcycle fuel systems so I took a chance it would be OK on my models.