Sand in motor

[cobrapowersys]

I was wondering if anyone knows how to clean out sand that has gathered in my powerhead. I have a 2001 yamaha OX66 250 HP on my 268 Islander, and I recently changed the thermostats. When I removed the old thermostats, I noticed that the old thermostats were badly corroded, and there was sand in the area below the thermostats. Is there a proper way to flush that out?

 

[richie rich]

Check with your local Yamaha/Grady shop..they'll tell you the right way to do it......but I have seen guys pull their therms out and run their engines just with ear muffs to flush things out.

 

[gw204]

Don't know if it's right or not, but I pull the thermostat covers and thermostats and then hold a garden hose to the openings the block and turn the water on. If you position the hose just right and hold it really tight, there's actually very little leakage. My thinking behind this is it will push things out the way they came rather than trying to force them through the motor.

 

[Tucker]

My motors were never flushed before I owned them. I got a 55-gal plastic drum and cut off about 9" from the top, I've never had much luck with the muffs. I ran each motor in 2-15-minute intervals with salt-away and let the water cool for about 10-minutes in between. In the end I got a layer of what appeared to be sand and white crap in the bottom of the drum after flushing each motor. Maybe..a cup (probably my head gaskets). Can't tell what color the water was from the crud because the salt-away is blue.