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Discussion Starter #1
So I was riding down the road when I suddenly lost power. I pulled over and tried to restart the bike but it will only start if I have the throttle all the way open and while I have the starter engaged. Then It immediately dies. I think it is flooding because I can smell fuel and there is some grey ish smoke coming from the exhaust. Also if I leave out for a few minutes it will run few seconds and then die again. This happens the other day and I took the carbs apart and blasted everything with carb cleaner and the problem seemed to be fixed but after another20 miles the same issue arose. My guess is a tiny crack in the floats. Anyone else think the same?
 

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Could be a stuck float, dirt/rubber in the needle valve.

Make sure the oil hasn't filled up with gas.
 

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Discussion Starter #3
The oil level is correct. I made sure to check needle and I didn't see any build up or anything. The floats did look sun dried. The hardest part of this is how to tell if I've fixed the problem or not.
 

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1986 VN750
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Are you sure it isn't POOGS?
 

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Discussion Starter #5
Pretty sure it's not vapor lock. The first time it happened I left the gas tank open for about twenty minutes and it would still do the same thing. This site needs to stop saying poogs and switch to vapor lock. More people will know what we are talking about. I have experienced vapor lock before and the engine is not acting like it's out of gas.
 

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Discussion Starter #6
one thing that i forgot to add was that upon inspection of the float needles i did notice a ring around the tips. i just wasnt sure if it was normal or not at the time.
 

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Pretty sure it's not vapor lock. The first time it happened I left the gas tank open for about twenty minutes and it would still do the same thing. This site needs to stop saying poogs and switch to vapor lock. More people will know what we are talking about. I have experienced vapor lock before and the engine is not acting like it's out of gas.
Dear guy with 13 whole posts here. POOGS is not the same thing as vapor lock.


Vapor lock is a problem that mostly affects gasoline-fueled internal combustion engines.It occurs when the liquid fuel changes state from liquid to gas while still in the fuel delivery system. This disrupts the operation of the fuel pump, causing loss of feed pressure to the carburetor or fuel injection system, resulting in transient loss of power or complete stalling. Restarting the engine from this state may be difficult.

POOGS is caused by a block in the gas tank vent that keeps fuel from
flowing properly into the carb bowls. Basicly the same thing as putting your finger over the end of a straw keeping liquid from flowing out the end.
NOT the same thing.
 

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..have a vulcan good day!
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one thing that i forgot to add was that upon inspection of the float needles i did notice a ring around the tips. i just wasnt sure if it was normal or not at the time.
I was concerned enough to replace both my float needles showing that wear....

hth

:smiley_th
 

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Discussion Starter #12
Dear guy with 13 whole posts here. POOGS is not the same thing as vapor lock.


Vapor lock is a problem that mostly affects gasoline-fueled internal combustion engines.It occurs when the liquid fuel changes state from liquid to gas while still in the fuel delivery system. This disrupts the operation of the fuel pump, causing loss of feed pressure to the carburetor or fuel injection system, resulting in transient loss of power or complete stalling. Restarting the engine from this state may be difficult.

POOGS is caused by a block in the gas tank vent that keeps fuel from
flowing properly into the carb bowls. Basicly the same thing as putting your finger over the end of a straw keeping liquid from flowing out the end.
NOT the same thing.
ad homemin ? is that how we do things around here?

i used to have trouble with the vent hose and when i would say "poogs" people just looked at me funny so i just started saying vapor lock. it seems like a colloquial term for this site. it doesnt matter what you name something if no one knows what youre talking about.

i have an update though. got the bike back to my house and got everything apart. the rings around needles are gone due the the fuel cleaner i put in the tank. i did notice some divots there the needle sits on the float tang. i also put the floats in warm water and notices very small bubbles forming on one of the floats. i'm going to order new floats and gaskets and i think that should fix it.
 

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Crowley
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i have an update though. got the bike back to my house and got everything apart. the rings around needles are gone due the the fuel cleaner i put in the tank. i did notice some divots there the needle sits on the float tang. i also put the floats in warm water and notices very small bubbles forming on one of the floats. i'm going to order new floats and gaskets and i think that should fix it.
Make sure the float needles are in the right way... I was working on a Honda Rebel that would die shortly after running and the float needle was in upside down... The pencil tip end should face up into the carb, not down on the float
 

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I've been there. The problem is absolutely that it's running rich. Don't worry about vapor lock or venting. When the bike is cold it accepts the rich mixture but once it's warm it will die right away. The key is the ability to fire with pull throttle.

Unfortunate there no way to fix this with the carbs on the bike. In my case the plastic tip of the needles were worn away from too many additives.

-Robert
 

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Discussion Starter #15
i just replaced the floats and needles. polished the needle seats and adjusted the floats according to the manual. it is still doing the same thing but in a shorter time. it wont idle and after a couple of minutes of holding the throttle open it starts stumbling then slowly loses power and dies. the spark plugs are not wet. soo back to square 1?
 

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i just replaced the floats and needles. polished the needle seats and adjusted the floats according to the manual. it is still doing the same thing but in a shorter time. it wont idle and after a couple of minutes of holding the throttle open it starts stumbling then slowly loses power and dies. the spark plugs are not wet. soo back to square 1?
There is an easy procedure to check fuel level on the center stand. It is in the manual. If the fuel level is too high, it is definitely a problem. It will come down to floats and needle/seats.

I don't know about 'polishing' the needle seat. Most people I know are afraid to do more than SLOWLY clean them. I like to test n/s with a mityvac/vacuum, before i put them back on.
 

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Discussion Starter #17 (Edited)
the front carb is just under 2 mm above the top of the screw. the rear is 3 mm below the top of the screw. slightly out of spec according to the manual. is it safe to assume that the adjustments i make with float tang will directly correlate with the fuel level reading? i did this test ealier today but i didnt trust my findings because on the rear one after i opened the drain plug it would go to a certain level and then after a few seconds rise a few inches higher. i suppose i could attribute that to a fouled needle seat. this time they stayed level for the duration of the test.
 

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Discussion Starter #18
so i bent the tang on the rear float up 3 mm. it would hardly fit in the bowl and there was no room for the needle to open. anyone know how to calculate the adjustments for this? in the manual it makes it seem like a trial and error thing. unless i missed something.
 

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3mm the float is like half a hair on the tang like if you rotate your shoulder 5 degrees at the base with your arm fully extended then the tips of your fingers have moved a lot more distance
 

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Discussion Starter #20
i cut a sliver of a tape measure out and had it places between the tang and float arms. if i understand your analogy correctly are you saying the point of measurement is the tip of the float opposite of the tang?
 
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