Milky water in carb throats

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Starcraft423

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Need Help: 70hp 3 cylinder Evinrude think 1982 model. Motor wouldn't hardly idle or when u put the boat in gear would quit would take 3-4 try's to get going. But on top end running motor doesnt miss a beat. So I cleaned all 3 carbs now motor will idle and take gas without quitting. But noticed a cloudy milky water substance in all 3 carb throats. Doesn't have hardly any gas smell to it. Where could the water be getting in at? Checked the compression on all three cylinders all 3 are holding around 120. Some say cracked head, head gasket, exhaust plate gasket,etc... Need help thanks in advance
 

F_R

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Re: Milky water in carb throats

Two real possibilities:

1. From the gas tank. Water in the gas.

2. From the atmosphere. Condensation. Was it running on a real humid day? The venturi action of a carburetor makes it run cool. Water can condense just like on an iced tea glass. It's harmless.

The head, exh cover etc are known problems with serious consequences, but no way can the water get way back to the carburetor throats from there.
 

Starcraft423

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Re: Milky water in carb throats

Ok thanks alot that pretty much sums it up for me. Yes it's been very hot for the past two weeks here but wasn't that bad yesterday while working on it prob the upper 80s. But for the past couple of weeks it's been 100 + here
 

Starcraft423

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Re: Milky water in carb throats

Talked with a guy the other day and seems like everyone tells me Head Gasket but all 3 cylinders hold compression and no water in gas tank. Then another guy tells me if it was the head gasket there's no way it could push water back to the carbs. Others say to just run the crap out of it to see if it straightens up. Afraid to get out on it and run it much any water in the carbs this milky stuff can't be good and if it's a head gasket or cracked head or block it'll end up burning a hole in a piston and end up with more problems and Help?
 

Haffiman

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Re: Milky water in carb throats

Mostly nothing to worry about, close to normal. It is all a combination of temperature, humidity and spit-back from the carbs.(oily fuel vapors mixed with humid air)
To reduce, see to that all gaskets for the sir-intake box are sealing properly and that the engine is not over-loaded and reaches its close to max allowed rpm at full throttle. It may be a sign that your leaf valves are getting weaker and not sealing 100%.
 

F_R

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Re: Milky water in carb throats

Talked with a guy the other day and seems like everyone tells me Head Gasket but all 3 cylinders hold compression and no water in gas tank. Then another guy tells me if it was the head gasket there's no way it could push water back to the carbs. Others say to just run the crap out of it to see if it straightens up. Afraid to get out on it and run it much any water in the carbs this milky stuff can't be good and if it's a head gasket or cracked head or block it'll end up burning a hole in a piston and end up with more problems and Help?

I told you up front there is no way a head gasket or exhaust cover gasket leak could find it's way clear back to the carburetor throats. That would be like trying to swim UP Niagra Falls. With a dam in the middle of the falls.

Gasket leaks are common, but let's not blame everything in the world on them.

ALL carbureted gas engines will get that condensation under the right conditions. In fact, in the old days airplane carburetors would freeze into a block of ice and crash. It didn't take designers very long to figure out the carburetor needed some sort of heater. Most modern engines have some sort of means of changing the environment in the area to prevent it. In your case, it is the motor hood, and warm powerhead inside, temp controlled by a thermostat.
 

emdsapmgr

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Re: Milky water in carb throats

Just wondering: have you taken a fuel sample from the bottom of the fuel tank to see if there is any water in the gas? FR is right on the money.
 

Starcraft423

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Re: Milky water in carb throats

Have checked the gas no sign of water also tried running engine on a different tank with same results motor idles and takes gas then becomes sluggish and dies.
 

Chuck4741444

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Re: Milky water in carb throats



I told you up front there is no way a head gasket or exhaust cover gasket leak could find it's way clear back to the carburetor throats. That would be like trying to swim UP Niagra Falls. With a dam in the middle of the falls.

Gasket leaks are common, but let's not blame everything in the world on them.

ALL carbureted gas engines will get that condensation under the right conditions. In fact, in the old days airplane carburetors would freeze into a block of ice and crash. It didn't take designers very long to figure out the carburetor needed some sort of heater. Most modern engines have some sort of means of changing the environment in the area to prevent it. In your case, it is the motor hood, and warm powerhead inside, temp controlled by a ther
 
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