2000 200hp Saltwater series 2 stroke waterpump kit missing washers

[zenoahphobic]

It’s got to be said again why are water pumps on Yamahas so varied in componentry and tricky?
Water pumps are simple devices and are not required to work very hard, And in any other engined vehicles, they generally last a very long time.
I guess the issue with them is that they are positive displacement pumps required to raise water a few feet up in an open non recirculating system and are hindered by their location on the drive shaft.
Wouldn’t it be nice if outboards came with a recirculartry system, with a simple centrifugal pump driven off the crank like an oil pump and a small stainless steel heat exchanger housed in the massive cowlings that engines come with these days! Will also eliminate corrosion and build up of deposits in the fine cooling passages.
Another design could be to be driven by an electric motor requiring only to work at idle, then water be pushed by the motion of the boat underway.

[Keithbaja]

Careful what you wish for.. just finished a article in latatude 38. Owner yanked the diesel, fuel cell and all. Installed a electric motor. Batts and has no smell, clean pwr. More room below and while Sailing the Batts get recharged by the prop turning while underway. I think was a 32 ft. I think she made 5/6 knots. Not a pwr boat. The impellers we use to today are centrifugal at higher speeds. Part of the reason some motors will run overtemp is a old/stiff impeller dosnt flex/bend enough for water to fly thru the pump.. very little known fact.. Someday electric it's coming to outboards !!