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bgreen82

outboard muffs for merc 15

16 posts in this topic

are there special muffs you should get for specific outboards, and can you only find them at certain places? gotta get my boat geared up quick, the urge is coming to get out.

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I've used the same muffs for every outboad I've owned. Starting with a 9.9 Mariner up to the Yamaha F150 I have now.

You can get them at Fleet Farm, Gander, Cabelas, West Marine or any boat dealer.

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Once upon a time I had a 9.8 Merc and muffs wouldn't fit it. Had to use a trash can full of water instead.

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so i bought some muffs w/o looking at motor(at folks house) and now that i checked it the water intake isnt on sides of lower unit. if its what i think it is, it is on the bottom of the fin just above the prop. is that correct? if so, i took the prop off can i use the muffs vertically with the hose end on bottom going up and in? if not it was only 5 bucks.

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I'm interested in hearing from those that have used/use the muffs succesfully. I put them on and had a fair amount of water running outside them so I didn't trust to start the motor, because if the water doesn't get sucked up in the engine to cool it, just a few seconds of running it can burn the impeller. Do you just trust that it's going to work and give her heck? Or should the muff create a better seal than what I'm seeing?

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mine do the same thing and ive had my motor running 10 min to get all the fuel outa the lines, the water is going to run out the sides cuz where else can it go besides be stopped.. when you first hook it up let it idle untill it pees then you know its working

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Yes you can use the muffs by putting it under the fin with the water running up. Just watch to make sure the water is peeing out. I have never had a problem doing it.

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Yes you can use it that way. Be sure it sucks the water good. You can leave the prop on, but BE SURE not to put it in gear.

If the arms of the muffs are of metal you can squeeze them a little to have better grip to painted surface, and be sure the end with the hose attached is the one that is against motor intake.

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I'm interested in hearing from those that have used/use the muffs succesfully. I put them on and had a fair amount of water running outside them so I didn't trust to start the motor, because if the water doesn't get sucked up in the engine to cool it, just a few seconds of running it can burn the impeller. Do you just trust that it's going to work and give her heck? Or should the muff create a better seal than what I'm seeing?

There will be water running out the sides. No worries. Fire it up!

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I have a Merc. 9.9 4stroke and muffs will not work as the water intake is on top of the cavitation plate. I have to use a small garbage can to run the motor if it's on the trailer. You may be able to position the muffs (I haven't tried) but I don't know if enough water will be pumped properly to the engine powerhead. Water may spit out of the indicator, but that doesn't always mean water is cooling the engine itself...might have to touch the engine to see if it gets too hot.

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For those with water intakes located under the caviation plate, mercury makes these:

3998_reg.jpg

That work well for your application.

marine_man

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Might give 'em a try then. Quick confirmation if you would. For a '95 Merc 150 XRi, the water intake is the "finned" slots (for lack of better description) on either side on the lower unit, and I just need to make sure I cover those with the muffs, right?

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Thanks MM. I see another thread going about waiting for the thermostat to open before it will start peeing, and feel the block and lsiten for the horn, so I'll give it a whirl.

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