When I got this, it didn't run (of course); a good cleaning and lube took care of that, so now it runs pretty well. I purchased a set of brushes, and figured if it ran ok as is, it would run really well with a new set. I installed the set, and found that there was too much pressure(?) against the commutator, is it wouldn't run until I bent the brushes slightly so they didn't press so hard. It then did run, but took a lot of current to do so, and ran very hot, so I put the originals back in, and it's fine again. My question is; has anyone seen this before? I know at some point I will have to replace those original brushes, so what am I missing here? This is definitely the first time I've seen this, in some 40+ years of modeling... Mark in Oregon
3 and 5 polers have different brushes. Don't know what happens when wrong type is installed. Does it run without the trucks ?
What you are described sounds like you got the wrong brushes 8988 is for 3 pole motor 89881 is for 5 pole motor The little brass arm is the same for both but the little carbin piece at the end is different. If memory serves me right the carbin for the 5 pole is smaller in diameter than the 3 pole verson A 5 pole motor will not run using 3 pol brushes A 3 pole motor may run on 5 pole brushes. But it will run hot, over heat and eventually burn out the motor.
It certainly seems to be the case, although both the parts box and the invoice show them to be "#8988". So now I'm not sure what to do, when the time comes that the old brushes really NEED to be replaced...suggestions? Mark in Oregon
Check the motor and make sure you really have a Marklin 3 pole motor (if you cannot see the poles ... in general the motor casing is clear for 3-pole and black for 5-pole). If you bought this locomotive used somewhere, a previous owner might have added a 5-pole without your knowledge. If that's the case, then you need 89881 5-digit brushes. I have never tried 3-pole brushes in a 5-pole motor, but this may be what might happen in such an instance. If it's a 3-pole motor, then you do have the right brushes (I did send you a 4-digit 8988, as that is what you ordered) ... sometimes, the "extra meat" on the brushes cause more contact. The bending as you did is the right strategy, but sometimes the brushes need to wear a bit to become more smooth-running ... as they wear, they mold into a rounded shape to better accept the commutator's rotations. Also, make sure that the brushes are completely seating on the circuit board at the top FLAT ... any gunk underneath or slight offset in the seating onto the board might translate into extra spring force of the brush tip applied down at the commutator. Questions: How do you know that the heat is more than normal operation? How did you know that more current was required? Do you have an ammeter hooked to your power supply? My suggestion is to break in the brushes a bit more and then see how it goes. I might also suggest a tiny tiny bit of Atlas 192 conductalube on the brush tips themselves. In all honesty, I would ride the brushes as far as possible ... simply clean gunk from the brushes - Many times I find that simply cleaning old brushes is all that is needed to get a locomotive running smoother.
Hi Frank Yes, you did send exactly what I asked for )) and yes, the motor is indeed the 3-poler: clear casing and I did count the poles. I do not have an ammeter, but my volt meter showed that with these new brushes it required 5 volts just to "break loose' and start moving, as opposed to the 2-3 needed by the old (original?) brushes. After a lap or two around my layout the motor housing was almost too hot to touch; with the old brushes, it'll get "warm" after 15 minutes of constant running, but not "hot". I will let it go for the time being, and then indeed try the new one again...with great caution! Thanks. Mark in Oregon
As kind of a post script to this thread... I ordered another set of brushes, just to try another set to see if it would make a difference. They arrived yesterday (thanks, Frank!) and I installed them this morning. The first thing I saw when I took them out of the box was that the little carbon bits were noticeably smaller than on the previous set. Anyway, I put them in the loco, and away it went, just as nice as you'd want. The starting voltage is still a bit high (which I'm guessing is par for the course with Marklin), but the over all speed range is already vastly improved, and I suspect that, after these new brushes get broken in, it will continue to improve. So there you go. Just one of those things, I guess... Mark in Oregon
