I started up the hammer today. I put on the rabbit ears and turned the faucet about 1/2 turn. Started her up and turned the faucet another 1/2 turn. Idled real nice. Let it run for about five minutes. Turned it off and the rabbit ears popped of from the water pressure. Was I supposed to turn the hose off before turning off the boat? I had the valve opened about 1 full turn.

You need to buy the mercruiser flush kit. It has a rod that runs through the lower unit hole and suction cup clamps the other side. This precludes muffs from falling off. Cost about $12. Can be had at any reputable mercruiser dealer.

When you turn the water on or off doesn't matter, as long as its on whenn the boat is running. Make sure you have plenty of water running then, like on all the way.

Yeah, The muffs suck...they can pop off at anytime.
I used the one with the rod that runs through the pick up holes too.

I bought this piece of crap from a merc dealer. I even asked the parts guy to get it for me to make sure I got the right one. I guess my concern was the pressure on the head gaskets when I turned off the motor. It was sucking the water in like crazy when it was running. Is there any danger to the head gaskets from the pressure from the water when the motor is turned off? By the way , you guys have a nice Thanksgiving.

The seawater pump actually sucks the water into the motor. Without the motor running the impeller is not turning, so no water will enter the motor.

You probably have very good water preasure. With the muffs I always use the ones with the rod or bungie cord it in place real well. If that thing falls off when you are running the motor you will make quick work of your water pump inpeller and houseing.

Jon

I also use the muffs with the rod that goes through. Only way to go, in my opinion. You don't want that thing falling off while you are the boat adjusting the timing or idle. When the motor is not running, water blows out past the muffs. I doubt if you could get water pressure to build up very much inside the engine unless you have extremely high pressure and volume There are bypasses even if the thermostat is closed. Any water that gets past the seawater pump will just go out the exhaust .

You did right.
Water On> motor on> motor off> water off.
By turning water off before the motor, you run a very good chance of the ruining impellor. Like a 100% chance.

This might sound kind of lame but works very well on my Bravo 1. My muffs don't fit tight and I don't trust them to stay on so when I put them on I wrap duct tape around the muffs & drive a couple of times. Holds them on tight for lots of water and they won't come off. One more use for duct tape!