Home made one here. Plunger with a hose connection using brass fittings from Lowes or Home Depot. Level your boat, cut the plunger handle where the plunger will be partially compressed against the hull and turn the water on about 1/3 open. The water will pour out around the plunger until the engine starts and then you should she a small steam of water coming out of the plunger. In a minute you should see water coming out the exhaust.