Don't try and pump your engine until you get to know some of the old time firemen in your area and get their help.
The first thing you want to connect up to a water source like another engine or pressurized hydrant and Back Flush any rust/gunk/mud out of the lines before you spin the pump. It might be a good idea to open the top of the tank before you get it wet and wet/dry vacuum any sepiment/rust out of it as well (mine had about 4" of mud in it). A little PM might keep you from breaking a hard to replace part. I think you can still get wear parts for waterous Pumps, don't know about pump housings or impellers...
I took my engine to a local Muster and got a real education on how to run my set-up...My truck has a 500 gpm mid-shaft pump and a 30 gpm PTO Pump that puts out close to 1000 psi of water through the booster reels.
The Westminster Muster is a great one for this as the pumps line up around a large farm pond and it's easy to move trucks around to support you, where Harrisburg all of the trucks are in single file.
Mike B
