very cool carb and intake manifold causing moisture

racerone

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Timing on these motors does not go out of adjustment.-----Unless of course someone molests the linkages.-----Make sure throttle plate is closed at idle.-----Make sure throttle plate does not open too early.
 

flyingscott

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Are you still doing this all in your Driveway? E 10 is fine to run in that motor no need to waste your money on more expensive gas. Racer is right about the gas cooling the carb down. And about the doing a link and sync.
 

bottomfish

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Are you still doing this all in your Driveway? E 10 is fine to run in that motor no need to waste your money on more expensive gas. Racer is right about the gas cooling the carb down. And about the doing a link and sync.
I ran it in the inlet. I'm thinking E 10 is no longer here. They took the up to 10% stickers off the pumps. Who knows what ethanol percentage it is now without testing it. There are some flat areas on the roller that was also seized. I unstuck the roller and checked the sync which seems ok. Thanks for all the great information.
 

bottomfish

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Timing on these motors does not go out of adjustment.-----Unless of course someone molests the linkages.-----Make sure throttle plate is closed at idle.-----Make sure throttle plate does not open too early.
The sync seems good other then flat areas on the stuck roller
 

bottomfish

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It’s been awhile since my last post. It was 90 degrees while out Sunday . After trolling for an hour the top of the intake was covered with moisture and the carburetor was also covered with white slug like moisture inside and outside .Definitely looked like oil, gas and water mix. The tank was drained and cleaned before.No separation of water in fuel test .i don’t understand why moisture and white sludge is forming on the outside of both The spark plugs have no sign of burning water, which would be obvious. 90 degrees or 50 degrees out it’s the same thing
 

racerone

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The fuel evaporates.-----That requires heat.-----Therfor the carburetor get cold.----Then moisture from the air condenses on the cold metal.-----No different than a beer can or glass on a hot day.----Simple as that.
 

jimmbo

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Ever take a Pitcher of Ice Water out of the Fridge on a very Humid Day? Ever notice how water is suddenly on the outside of the Pitcher? Same Thing is happening inside the Carb throat, Enough Ice can build up at the Throttle Plate and effectively seal the Carb closed. That was referred to as Icing.
 

tphoyt

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Still not sure what say. As mentioned before I have seen it happen. Maybe yours is worse than what I have seen. Can you post a pic?
Checked the running temp? Thermostat in working order or even there? Lots of people just take em out but they are important.
 

bottomfish

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Still not sure what say. As mentioned before I have seen it happen. Maybe yours is worse than what I have seen. Can you post a pic?
Checked the running temp? Thermostat in working order or even there? Lots of people just take em out but they are important.
 

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tphoyt

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To me this would be normal especially if your just trolling around for hours and not generating any heat under the cowl to help displace the moisture. But that’s just me. Sorry I can’t be of more help.
 

racerone

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It is the basic principal of refrigeration.-----" An evaporating liquid needs heat "-----In a refrigerator the heat is pulled from your ice cream or other treats.
 

tphoyt

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That just brought back memories from automotive tec class when the instructor said there is no such thing as cold just less heat.
I’m pretty sure half the class laughed thinking he was making a joke. But it’s true.
 

Crosbyman

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any chance you can rig something to cause more heat transfer from the engine block to the thermostat body.

thousands.... of your engine mdl are all having this issue or just yours....??
 

racerone

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You have to wonder why small aircraft have a lever marked ----" carburetor heat "----I believe that is meant to prevent carburetor icing !!!
 

F_R

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Old cars with carburetors had intake manifold heat riser valves to transfer some heat from the exhaust manifold to the intake manifold. In the army, I had responsibility for a gasoline engine powered generator. Under certain conditions, that thing's carburetor would freeze up into a solid block of ice and the engine would quit.
 

Chris1956

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FR, the "stove" in old carb motors was to heat up the automatic choke, and cause it to open when the exhaust manifold (and engine) were warm. It was not designed to prevent icing of the carb.

Icing of the carb is only an issue on airplanes., and then only at altitude It does not affect boats.
 

flashback

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FR, the "stove" in old carb motors was to heat up the automatic choke, and cause it to open when the exhaust manifold (and engine) were warm. It was not designed to prevent icing of the carb.

Icing of the carb is only an issue on airplanes., and then only at altitude It does not affect boats.
Respectfully disagree, icing is expected in airplanes and a heat source is vital, here on earth it's not common but does happen, I've had several air-cooled v twin motorcycles that have electric heat elements in the carb.. seems unlikely on a boat especially with the motor and carb enclosed. But all it takes is the right temperature and humidity to ice up..
 

airshot

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Anyone consider his fuel that he is buying has water in it ?? Been there on that one !!
 
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