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D.A. newb with yet ANOTHER leaky float bowl Q

Fuel System: Gas (Petrol) tanks, Carburators
LOUD MOUSE
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Re: float pics

Post by LOUD MOUSE » Thu Apr 03, 2014 7:45 am

Are you sure the needle isn't depressed in pic 1?. ...lm

pojobey wrote:Float adjustment pic #1

pojobey
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Post by pojobey » Thu Apr 03, 2014 8:49 am

Reasonably sure. I laid it on the bench to take the pic but checked it many times holding it in one hand at a angle such that the tang barely came to rest on the needle and got the same result. What are your thoughts on the 1-1/8" measurement?

Thanks,
-pb

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Snakeoil
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Post by Snakeoil » Fri Apr 11, 2014 11:36 am

You said that the Keyster floats are different than the Honda floats. They may be of different buoyancy as well. So that means that the height setting would not be correct if the buoyancy is different. Folks making foam floats to replace the cork floats on vintage bikes have to make sure they get the buoyancy correct.

Float height is about fuel level in the bowl. Maybe it is time to make a fuel level tube so you can actually see what you have in the bowls. I've been thinking about doing the same, just for the pure fun of it because it would put the whole issue of where to set the floats to bed once and for all.

One thing to keep in mind here is the fuel comes into the bowl from above. The carb leans forward at an angle. So the fuel will want to run down the front wall of the carb/bowl as it fills the bowl due to gravity and surface tension. This has it flowing over the surface of the gasketed joint. So, I do not believe that fuel level is your problem. I believe the gasket is not sealing and that is why it leaks as soon as you open the petcock.

I did not see it mentioned here. Make sure that your floats are not dragging on the gaskets. I know that is a fuel level thing and I don't think fuel level is your problem.

I have one carb that started doing this least year. I've been into the carbs three times this last week and it has gotten worse. I have ordered new gaskets. Mine appear to be some type of elastomer. So, I may try "puffing them up" with a little carb cleaner. I'm not sure if my new Honda gaskets will be paper or elastomer. There is an outfit that sells elastomer gaskets I found on the web. $1.99 each so worth a try. Put the gasket part number into Google and you'll find them.

regards,
Rob

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Post by rrietman » Fri Apr 11, 2014 11:39 pm

LM' you are right. PB you have the needle valve depressed in both pics giving a HIGH fuel level. Rob, no need to reinvent the wheel here, set the float level to spec (gasket surface--no notch--no lip) good to go.
Randy

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Snakeoil
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Post by Snakeoil » Sat Apr 12, 2014 10:01 am

I hear you Randy. I'm a firm believer in specs. But with mine set at 22.5mm from the notch, the floats contact the roof of the bowl when you flip the carb over. I do not think that is right. If I use the gasket surface, that would make the contact more severe as there would be less spring compression.

Chase has an OEM float gauge that uses the notch and sets the floats at 22.5 mm.

Not sure if you've been following my thread on float height. I would say that it is unclear where to measure from, although I'm leaning towards the notch even though my floats hit the roof when using that point.

regards,
Rob

cknight
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Post by cknight » Sat Apr 12, 2014 11:46 am

Just measured a number of Pw26 float needles, and they all seem to have an overall length of 15.5mm, without any preload on the spring. Measured some floats, and they're 32.75mm diameter. Maybe a clue? Chase

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G-Man
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Post by G-Man » Sat Apr 12, 2014 12:13 pm

rrietman wrote:LM' you are right. PB you have the needle valve depressed in both pics giving a HIGH fuel level. Rob, no need to reinvent the wheel here, set the float level to spec (gasket surface--no notch--no lip) good to go.
Randy
Randy

Measuring the fuel level is not reinventing the wheel. As we can see here, the 'secondary' method of measuring some arbitrary dimension which may or may not give you the correct fuel level is confusing and open to interpretation.....

The engine cares about the level of the fuel in the float bowl not how clever you are at guessing the position of a bit of brass......

G
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