Flushing engine and waterpump

[Jim Fromm]

My son and I have an ongoing argument. We have a 2003 40 hp Yamaha, It runs beautifully. I recently bought a waterfront lot. I want to keep the boat in the water since there is no lift. I think if I flush the engine out with freshwater after each use, by using the hose connection on the side of the engine and do not run the engine, it will rinse out both the engine and the water pump. He was told that the engine and water pump can only be flushed out properly if it is running and being fed fresh water to the foot with the earmuffs. We need some expert advice since I intend to leave the boat in the water for the season.

 

[hardwater fisherman]

I think to flush out the entire cooling system you will need to run the motor to circulate the water through. But I have never been in salt water so maybe somebody will steer you right.

 

[Chris1956]

The flushing you will get is based upon the design of the flush port. The correct answer will only be had from Yamaha. Perhaps the owners manual will shed some light.

 

[82rude]

Check your manual but for example my 2011 60 etec specifically states that the motor does not have to be running for you to properly flush the system using the flush port.Yamaha may be different .

 

[Sea Rider]

Some OB's needs to be water flushed while ON for thermostat to open and flush correctly combustion & head area, if flushed OFF will never salt clean that area. If having a flush connector on power head or back of lower cowl will be much better and friendly to flush with. Check which ON-OFF state that OB needs to be for correct flushing.

Happy Boating

 

[82rude]

Do a search on line for an owners manual.Ifound a couple easily in pdf format and I must say Yamaha has an excellent in depth owners manual.I believe they want you to run the motor when flushing.