water cooler for finned motor?

yes its for a boat
anyone got any ideas on how to build a water cooler system for a neu castle 2200kv motor

I'm thinking of just making a coil around motor with aluminum tubing...would copper be better?...easier to bend

be pretty nice if you could devise some way of making a slightly bigger can to fit around the fins and sealing the ends with o-rings and sealant like on the smooth can coolers where the water actually flows over the motor