alcor

After making a high speed pass, I pull the throttle off to one engine to check spark plugs and slowly pulled back on the other engine idling in the rest of teh way to teh dock on one engine. Put it on the trailier and took it home.

Pulled the plugs, look fine. Started the engine to flush it out and no water came out of the mufflers. Checked the through hull pick-up valve, it was open. Started it again, no water out of the mufflers. Pump was turning. Decided to close the through valve to force water into the pump; you know how water comes out of the pick-up till the engine starts when flushing. Water came out through the muifflers fine. Shut it down, opened the through hull valve and started it again; no water out of mufflers; all water coming out of the hull pick-up looks like to me. Best I can figure is shutting that engine down at high speed forcde water against something in the system any thoughts?

Wally

iTrader: (1)

Hold on a sec....are you flushing on the trailer? boats out of the water? well then you'll never get water to come out the mufflers if the thru-hull valve is open....
Most garden hoses are 5/8" and depending on the city water pressure can supply about 5 gallons per minute......now the hose on the boat is 1-1/4" and the sea-water pump can pump WAY more then the garden hose can supply it.....But thats actually not the problem here....the problem is that with the thru-hull open your draining all the water before it can make it in to the sea-pump....and possibly burning the impeller out at the same time....you need to slightly close off the thru-hull valve...BUT NOT ALL THE WAY...since the garden hose cant supply enough water if you close the thru-hull all the way you will most likely collapse the intake hose and the garden hose when you start the engine up (Been there done that!!!) So you need to have it cracked open enough to let some air into the system so the hoses dont collapse. Hope that helps

Pwrbt33

iTrader: (2)

Be careful also when doing the high speed shut off's, the engine will sometimes "deisel" backwards and flip the impeller blades backwards. This will sometimes break some vanes if it has any age on it.

John

Dangerous Dave

I flush my boat all the time with the thru-hull valves open but my hose hook up dumps right into the sea strainer. If yours does too, you probably need an impeller.