Sturmey Acher AB3 internals issue.
I have a Dutch Gazelle, bought new on Secember 30th of 2013, less than 250 miles put on it. The issue has been progressive. My indicator rod has broken off today but prior to this, the hub has been giving me some trouble. The issue has been happening for about 3 weeks now. The hub was very over geared for this heavy bike and I changed the cog from a 19t Sram to a 22t Sturmey last week. Put everything back the same as I took it off, but for some reason the hub would never keep the gearing right after adjustment, and it would slip sometimes when pedaling with moderate or hard pressure, and slow shifts. Sometimes I would shift and the hub would as well, but I'd feel slippage till the hub clicked the gear into place. The problem would sort itself out for a while and suddenly come back and go away. Today while riding the hub suddenly wouldn't stop slipping (around after 5 miles of riding), and the wheel wouldn't spin freely, nor would the cranks turn freely without the hub giving resistance (forwards and backwards). Took it to the shop I bought it at today and they looked at it, took the wheel off, and adjusted it and the shifting, and the slippage was minimal for a few minutes after i left, then more slippage started happening again like it was earlier. I adjust it again and it stopped the slippage and the hub shifted fine. Then my indicator rod snapped off with the threads still engaged, shifted to 3rd gear, while the hub gave the wheel and cranks resistance again, so much so that I couldn't pedal easily. It also engaged the brake drum on it's own, which i loosened, but still had a bit of intermittent resistance afterwards.
The slippage wasn't limited to any single gear, it happened in every gear, and sometimes it would prevent the shifter from sliding the hub into the next gear (without pedaling), or keep it in only 2 gears (shift from 1-2, or 3-2, no full range). Right now the cranks still spin with the resistance, and i can ride it in 3rd (with slippage).
Can anyone help me with what may be wrong with this hub and how It may be fixed?