Get you a good set of Stern Drive water muffs. Don't waste you money on the cheap ones.

 

Thanks. Any suggestions on what "good" is?

Also I have no idea what these look like or how to put them on or anything..

 

They look like this. I can't comment on what is a "good one"

 

I would imagine this has been covered here before, but I didn't find it via the search function. Oh well.

It's pretty basic:

-- Make sure your drive is down in the "run" or "trim" position, not the "tilt" range (you should know all about the difference, now - based on your other post :smt001)

-- Attach muffs with a good water supply. Water will be squirting out quite forcefully from around the muffs.

-- Start the engine. Check to see that the muffs stay attached as sometimes it can slide off.

-- The "better" muffs (as mentioned above) will actually have a small rod that goes through the water inlet. It prevents the muff from sliding off by connecting the two halves of the muff together.

-- Not necessary, but I also make it a habit to see that I have exhaust water exiting through the bottom of the transom plate. (3.0L 4cyls will only exit on one side). To see what I mean, feel around the bottom of the transom plate - you'll find two holes that you can stick your fingers in.

 

I have read that you should not turn the water on all the way. Keep an eye on the gauges.

 

IIRC, that's more in regards to outboards (maybe smaller ones). Won't be a problem for stern drives.

 

Rex. I recommend the Quicksilver Flush kit. It has a pin that connects the two side through your pick up veins.

I don't like the others shown because they can fall off if not monitored.

I like to turn the water on(I do it all the way, never had an issue) Start the engine, let run at idle for 10-15 minutes, while I wash the boat, then turn the engine off, then water. It wouldn't be good to have the muffs fall off while I'm on the other side of the boat, smoke the impeller and have the engine overheat.

 

I don't like the others shown because they can fall off if not monitored.

+1:thumbsup:

 

Why would you not turn the water on all the way? I actually shorten the length of hose I have attached to reduce pressure drop and thus increase overall flow.

Besides looking at the water coming out the transom, you should notice visibly less water escaping from the muffs when you turn the engine on (i.e. more into engine/less on ground)

 

The too much water caution definitely applies to jetdrives - I have an Evinrude 115 on my BW Rage 15 and if you run the hose into the drive at full force or even at all prior to starting (there is no impeller on these - the jet pump feeds the water into the motor), you can actually flood the cylinders with water - which could cause havoc if you cranked the motor in that condition. This is due to it being a 2 stroke. I would imagine that this type of flooding could possibly occur on any 2 stroke outboard engine.

 

I always ran full water pressure on my other boats with no problems. My 1988 Sea Ray and Merc IO owners manuals say do not run at full pressure. I thought it was funny because everyone has different water pressure at the sillcock. :huh:

 

I've looked through my Mercruiser manual and saw nothing about giving it to much water. It did recommend you not exceed 1,500rpm due to the potential for insufficient water. Whether their warning is due to concerns of water supply volume itself or the fact pump suction may collapse the hose and restrict supply are beside the point.

 

The too much water applies to smaller outboards where you can over welm the water impeller. I would echo buying the muffs with the wire through. It delivers more water to where you need it and the surface area is a little larger thena the other ones. I use the other kind on my fishing boat and it works fine but not so great on the outdrive.

I don't use a flush kit because I have the internal flush kit installed and recommended by MM which Mercury now says they don't like but that is a lawsuit for another day.

 

Picture of owners manual is not very good. Sorry.

 

My Service manual #31 for 5.0L/5.7L/6.2L MPI

Says to turn the water on 1/2 way.

 

I use the cheapie muffs, but I tie it on so it CAN'T fall off. Full flow won't hurt anything because it will just leak out from under the muffs. As you start it, more water gets sucked up, but it still leaks so you know there is plenty of water getting into the impellar. I just want to make that it's lubed, I'll be watching the temp!

 

My 250 manual (5.7) said to rinse at idle. After replacing the cockpit heater heat exchanger twice in 4 years, and the hot water heater once, I started rinsing at 1000 RPM and both lasted the next 6 years without problems. The accessories on the engine's raw water system need extra oomph to get a good rinse.