Fresh Water Flush

Bob Meola

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When flushing engine with fresh water while in the slip do you tilt engine up or leave down?
 
Fish is correct. Tilt all the way up, get the water started, and you'll see a small stream coming out of the prop hub and the side vents on the lower unit. Keeping the engine in the "down" position in salt water won't let the freshwater flow thru the lower unit.

Make sure it's peeing out the telltale.
 
In terms of the upper motor area, it doesn't really matter, up or down but what does matter is that when tilted down and in the water, the local sea water will flow into the lower unit. The general approach is to tilt up the engine, flush with fresh water and leave up till next outing.
In cases where the temperatures may drop below freezing, it is best to leave the motor tilted down so that fresh water will drain out. Fresh water if left in the motor can freeze and cause damage.
 
I had always flush in the up position. Suzuki recomemds flushing in the down position to unsure that the head is flushed properly.(says it in the manual)
Obviously, if you are in the water, you are not flushing the lower unit of salt water that way.

You could start by flushing down and then raise to flush the lower unit.
I think thats a pain with twins.

I have been flushing in the down recently. mostly because it is easier because the flush port is on the front of the Zukes.

So the answer is either way is better than not flushing
 
My humble procedure:

I have a pair of 250's. At days end back into slip, tie up and shut down. Hook up both motors to a Y valve splitter we made up. Turn on water and simultaneously begin flushing in down position. Open beer. Start drinking beer while filling wash bucket with another hose. Rinse exterior of motor cowlings and transom area then wash and rinse. Open another beer. Use absorber towel to dry cowlings and transom area. Remove cowlings, check oil, put cowlings back on. Raise motors while still flushing. Wash and rinse exterior lower units thoroughly.... Next (hopefully) unload fish. Open another beer bragging about our fishing prowess (engines still flushing now in up position with catches down and trim pistons retracted). Wash and dry rest of the boat. Now shut off and remove engine flush hoses, slip on cowling covers. Open beer, eye .... the boat, talk more s#!t. Yep, that's 2 over the recommended limit but ... it's the weekend !!
 
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I don't flush because I'm on a mooring. Millions of other boats in a similar situation that have put thousands of hours on their boats without a problem.

Sound the alarms!
 
I have twins in a slip and I uea a y valve to flush both engines at the same time. They flush in the tilt up position. When the flush is near completion, I lower the starboard engine to gain the access to the port engine. Shut the port engine flush off and disconnect the flush hose. The starboard engine is still flushing while in the down position. Raise the starboard and let it flush for another minute in the raised position. Final step is to shut down 2nd y valve and disconnect the flush hose. Net 2 salt free engines
 
Occasionally it depends on the engine. Evinrude E-Tec do not tilt up to flush as water can enter cylinders due to high tilt angle. I flush on mooring using boats freshwater wash & flush port w/engine not running (which is EV recommendation). Flushes salt out of powerhead. Then let drain, tilt up, and rinse salt off lower unit.
 
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"Occasionally it depends on the engine". Evinrude E-Tec do not tilt up to flush as water can enter cylinders due to high tilt angle. I flush on mooring using boats freshwater wash & flush port w/engine not running (which is EV recommendation). Flushes salt out of powerhead. Then let drain, tilt up, and rinse salt off lower unit.
Correct ... mine are Yamaha's different manufacturers different procedures. Didn't the Yam F 350's have some sort of issue if you left motors up in cold weather residual water could get trapped and freeze ?? Older models maybe ?
 
Correct ... mine are Yamaha's different manufacturers different procedures. Didn't the Yam F 350's have some sort of issue if you left motors up in cold weather residual water could get trapped and freeze ?? Older models maybe ?
Yes, there were pockets near the tstats that trapped water that if subjected to cold temps could freeze and crack the castings
 
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