What kind do you have? If you have the older three pin connector type you can pry up the tabs and take them apart. Turbos tend to pump oil vapor into the insides and they get gummed up. Be sure to scribe some marks on the two halves to get them back together correctly. There's a small plastic cone shaped brush spreader that comes off when you pull the armature out. It needs to be removed from the can and installed on the end of the armature before you put it back together. I've read here that the newer two connector pin types can't be dissassembled.