Ears to Water Intake Yes-No?

[Don S]

Re: Ears to Water Intake Yes-No?

The water leaking out around the muffs doesn't hurt a thing, unless it pushes the muffs off. If using the U shaped muffs, I always tie them on. With the Merc muffs with the wire, they just can't get away.

 

[dcg9381]

Re: Ears to Water Intake Yes-No?

I dunno, after installing a reman engine, I put the hose the outdrive( bought 2, and modified it, so as too have 2 hoses feeding both sides)

Ran it up and kept it at 2000 rpm(old pos OMC 5.7-, please hold the applause)

Ran it for 20 minutes to make sure cam was splashed well.

Idled for 5 min, then used 5 minutes to pull cover of the impeller(applause now allowed)
I was missing 1.5 fins- 1/2 was in t/stat. rest was blown out the thru-hull exhaust.
Just my experience.

I ate my raw water pump housing and impeller because the muffs didn't clamp tight enough. I didn't know you could get a set that went all the way through.

After installing a new raw water pump (instead of just an impeller) I put an extra clamp on the muffs and made sure I had good water flow to the pump.


There's a shop in my area with a prop shaft dyno, my understanding is that they run on a hose connection... Thats at way above 3000 rpm.

 

[Don S]

Re: Ears to Water Intake Yes-No?

You can get away with running on a dyno with muffs if you have a lot of water going to them and you aren't going to be running at WOT or higher rpms for very long.
Best way (the way it should be done) is to use a test tank and allow the water pump in the lower unit to circulate the water. The pump for the dyno is water proof. Just run the hose in the tank to keep the temp down.
Even with a dyno, you REALLY have to pay attention to WOT, temp, water level. These things aren't toys.