It`ll probably depend on whether it`s for Grumpy,Dopey or Sleepy....! or more precisely the 1000,1200,or 1400...or maybe a T58 one,at a push...,are you running it in manual control ,or Computer ? Won`t last long unless you keep it clean,if it`s in salt water....Make sure you set the IGVs correctly,and have a mechanical HPcock,if it surges....!!