Ears to Water Intake Yes-No?

starsnstripers

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I've seen some posts on here before that said when putting the ears on to run engine out of the water it can blow a seal or cause leakage. 1) What is a safe psi input to waterpump at the ears? 2) Maybe you should start engine and then apply water pressure? When a boats in the water i'm sure there's not 40-50 psi input to the suction side of the pump. 3) What is the psi of the OD water pump at its outlet? Comments? Curious for future reference :) Or is a "T" fitting or"Y" valve in the water line from the OD to the engine an option but only in neutral because the OD pump would be dry if there was a shut off there? hmmm???
 
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Don S

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Re: Ears to Water Intake Yes-No?

I've seen some posts on here before that said when putting the ears on to run engine out of the water it can blow a seal or cause leakage.

Bull Hockey
 

Don S

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Re: Ears to Water Intake Yes-No?

1) What is a safe psi input to waterpump at the ears?
The muffs are NOT water tight, they leak around the outsides. I suppose if you found a way to seal them completely that you might damage something, but I doubt it.

2) Maybe you should start engine and then apply water pressure? When a boats in the water i'm sure there's not 40-50 psi input to the suction side of the pump.

Hook up the muffs, turn on the water, start the engine. I have done this with 50 to 70 psi of water pressure an never had a problem.

3) What is the psi of the OD water pump at its outlet?
3 to maybe 15 psi max.
 

starsnstripers

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Re: Ears to Water Intake Yes-No?

:eek: DON!!! You were speechless on that one huh? hahaha! OK, So hook up the ears and let her go ? If a leak occures it was a weak spot or wasn't right to begin with, RIGHT?
 

ziggy

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Re: Ears to Water Intake Yes-No?

Maybe you should start engine and then apply water pressure?
don't do that thats how ya start a jet ski.;).... it takes moments (like seconds) for runnin an impeller dry for damage to start happening..... wanted to add a pic of my impeller that had maybe 15 sec. of dry run on it. 50 hrs total.. i think it showed signs of being abused.... sorry, can't find the impeller to take a pic of it.....
 
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Coors

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Re: Ears to Water Intake Yes-No?

you can use the long a/c duct straps to try to keep the leakage down.
It will still blow all over the place.
Turn the water all the way up, if you rev it to 3500, you don't have enough water or pressure to feed the outdrive what it needs.
That means new impeller.
 

starsnstripers

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Re: Ears to Water Intake Yes-No?

Thanks Coors i was looking out for it getting to much. I'm all set thanks
 

JustJason

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Re: Ears to Water Intake Yes-No?

if you can get the muffs that are 2 peice with the metal rod that goes through the lower unit get those.... they stay on better. Nothing is worse than being on a 25ft cuddy under the hatch only to find the 1 piece muff have fallen off......
When I run them, i usually turn the garden hose up to 3/4... but not full.
Only run the engine at idle speed. A quik blip of the throttle (as to check if timing is advancing) is ok... but only a blip. Never run it up past idle for any period other than a quick blip.
 

Haut Medoc

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Re: Ears to Water Intake Yes-No?

You can run it @ 1500 rpms all day long.......;)
 

Don S

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Re: Ears to Water Intake Yes-No?

Turn the water all the way up, if you rev it to 3500, you don't have enough water or pressure to feed the outdrive what it needs.
That means new impeller.

Common missconception. It will NOT damage the impeller, it will still be getting enough water to cool the impeller and prevent damage. It may cause the engine to run warmer, but I doubt that either since you would only be running the engine that fast to check the advance timing.
With no load, there isn't much reason to run an engine that fast on muffs anyway.
 

starsnstripers

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Re: Ears to Water Intake Yes-No?

Thankyou gentlemen, just double checking on this is all want to do it right. Enough things go wrong without causing problems. Thanks;)
 

Coors

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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.
 

Don S

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Re: Ears to Water Intake Yes-No?

It wasn't for lack of water, if you had water hooked to the hose and even minimum water pressure, it wouldn't burn up the impeller. It's still getting water enough to cool the impeller and keep from breaking vanes off. IF the muffs fell off in the middle of it, well..................
 

Don S

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Re: Ears to Water Intake Yes-No?

One other note, no matter what your water pressure, if you have several 50' hoses hooked together and kinks in the hose, don't expect the impeller to survive.
 

Lou C

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Re: Ears to Water Intake Yes-No?

I use 3/4 in diameter heater hose instead of regular garden hose, it seems less likely to kink than garden hose. I also use the dual inlet muffs that Tempo used to sell, they fit tightly and supply water to both sides. To run at 2000 rpm, I don't know if most house hold systems supply enough volume of water. One thing with the Cobra impeller, if you had a problem with the vanes breaking off, if you don't get the big o-ring around the housing in right, it can suck air and the pump may not prime adequately.
 

Caveman Charlie

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Re: Ears to Water Intake Yes-No?

I also thought I heard somewhere to not open the the water to far open. Glad you guys set me straight. But, if I open my water pressure to high the muffs blow water out the side of them bad. So, I always try to keep the water pressure just high enough for a little leakage around the muffs but, not so much that water is spraying everywhere.

It always seemed to me that it would be nice to have the water going in both sides. But, the muffs that came with my boat were not built like that.
 

Don S

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Re: Ears to Water Intake Yes-No?

if I open my water pressure to high the muffs blow water out the side of them bad.

It will, until you start the engine, then much of it will go to the engine.

I always try to keep the water pressure just high enough for a little leakage around the muffs but, not so much that water is spraying everywhere
I sure hope you open the faucet some more once you have it running.
 

Caveman Charlie

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Re: Ears to Water Intake Yes-No?

It will, until you start the engine, then much of it will go to the engine.


I sure hope you open the faucet some more once you have it running.

The faster I run it the more I need to open the hydrant to keep a little water leaking out around the muffs.
 
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