Rebuilding Bukh DV20 Dynastarter

[unclebraddah]

Aloha. Anybody ever tear into one of these. A belt driven Starter Generator. The threaded post receiving the Power(from solinoid) started spinning and the dynastarter stopped turning.

I openend it up and saw bigger copper wires comming from each of the 4 windings(Copper wire wrapped plates attached to the body). The looked unhinged perhaps broken. So I soldered them together to the power post. I put two brushes on (with wires to the Wrapped plates) and everything was fine. I put the other two on and it started shorting. Basically I believe the body is a ground. When I attach the two brushes without winding plate attachents it puts a + current through the body.

Im trying to figure out how this thing works. By my reckoning...The power goes in to all winding plates and creates the current causing the shaft to spin connecting to the brushes bringing current to the D+ and field post(which I dont use as I have an alternator). I use the Dynastarter to turn the engine over. ant diagrams or understanding how these things work so I can put it together would be greatly appreciated. Thanks!

 

[unclebraddah]

ahhhh...vocabulary..My copper wire wrapped plates would be the stators I believe

 

[DownWest]

Can´t help on the wiring diag. I had one on a Haflinger and was warned that the brushes were special and not to use ordinary carbon ones for starters or generators.
Andrew

 

[pampas]

the "Plates" that you call them are the series windings of faily heavy guage, the lighter coil ends are the shunt windings for use when generating.
Tis a few years since I have repaired any and then I used to hate doing them, fiddly short ends ect. My advice to you would be to take it to an auto electrician, LSUK springs to mind. these things are really exspensive to buy new and hence not cheap to repair, Tell them that you only wish to use it for starting and they will configure it for that purpose . Thats the best advise that I can give knowing what these beasties are like and the problems arising. Best of luck.

 

[unclebraddah]

Still I am wondering how a motor works. The power goes into the winding wich creates the magnet that spins the shaft upon which the brushes sit creating voltage....so If I just run it without brushes..Will it turn?