Boat Runs on Ear Muffs Stalls in Water

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E_S_A_D

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In neutral it runs fine in or out of water (ear muffs). In water it stalls when put in gear. Ideas? Sometimes I can get it going in water and it runs great.

It's a 1972 50 hp Johnson.
 

bigpoppakdog

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Re: Boat Runs on Ear Muffs Stalls in Water

my guess is there an a low idle mixture screw? Backpressure in the water is way different than muffs in the driveway.
 

jtexas

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Re: Boat Runs on Ear Muffs Stalls in Water

can't judge how it will perform under load by running it on the muffs. even a crappy running outboard can sound great in the driveway.

Has it been like this since you got it, or it was fine now it's acting up?
What recent maintenance has been done to this motor?
How often you use it?
How old is the gasoline?
Time since your last carb rebuild?
What's your idle RPM, in the water in gear?

No need to guess...do a compression test and spark test, report your results. Inspect fuel tank for water/debris.
 

setlack55

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Re: Boat Runs on Ear Muffs Stalls in Water

I had the same issue with my 71 Johnson 60. Just tuned up the carb idle adjustment and it runs awesome now.
 

E_S_A_D

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Re: Boat Runs on Ear Muffs Stalls in Water

I had the same issue with my 71 Johnson 60. Just tuned up the carb idle adjustment and it runs awesome now.

This is great, thanks for your responses. It's at a mechanics shop now, I figured I'm not going to mess with it. I recently purchased it, it runs fine- it's just been a cold start then getting it to go into gear has been a chore.

I'm just hoping the engine isn't bad.
 

kenmyfam

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Re: Boat Runs on Ear Muffs Stalls in Water

Needs to be "fine tuned" in the water not on the muffs. back pressure is way different between the 2 scenarios.
My 2 cents.
 

E_S_A_D

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Re: Boat Runs on Ear Muffs Stalls in Water

My journey into boating has been a horrible start. Just talked to the mechanic. Boat will not go into gear in water after carb's being totally cleaned. Runs great on land on ear muffs, not in water. He's going to work on it more tomorrow morning.

Could this be a compression problem? He mentioned also, valves behind the carbs that could be clogged... but it's a several hour job. Great. My little old boat recently purchased is junk I'm thinking =(
 

bigpoppakdog

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Re: Boat Runs on Ear Muffs Stalls in Water

You mean it will go in gear while in the driveway, but not in the water??
 

E_S_A_D

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Re: Boat Runs on Ear Muffs Stalls in Water

You mean it will go in gear while in the driveway, but not in the water??

Correct. Runs great on the ear muffs, in water stalls out. Mechanic said it COULD be "valves behind carbs, but will take several hours to rebuild"?
 

91kuhndog

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Re: Boat Runs on Ear Muffs Stalls in Water

ESAD.... first things first. if the carbs have been cleaned, put the boat in the water, set the idle up 1/4 turn on the idle screw. It's the long bolt where the throttle cable goes in the motor. You'll see that it sits against the idle stop. Turn that screw in about a quarter turn, this will increase you idle in the water by about 100 rpm....in your case, enough to keep it running when put in gear. I don't buy the "Bad reed" issue....I'd say once the compression test is done.....and checks good, run some Sea Foam through the tank of gas, take it out and run it. Sounds like a boat that might have set up for a while. As a note,...the reason it'll run on the muffs is because it has no back pressure on the exhaust. Drop it in the water...now it'll idle considerably lower due to back presure... these motors and this forum are simple creatures....I've played with boat motors for over 25 years and I still come on here to ask questions.....good luck
 

JB

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Re: Boat Runs on Ear Muffs Stalls in Water

You get one thread per trouble, ESAD. This one is covered.
 
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