Scout running out of fuel

[Gone Looney]

I have a 101 scout with a m88 linkert that started running out of fuel for some unknown reason,the cap vent is free and I can blow back through the fuel line and it is clear,the vent in the carb is clear as well. When I turn the valve on with the fuel line off the carb it flows well but when I put the line back on the carb it quits flowing and doesn't fill the bowl. Any ideas?

[tfburke3]

Sounds like you have it narrowed down to the float valve assembly.
Check that the needle moves freely with the float,seat is unobstructed etc.
I like to attach the bowl to the line,not the carb and hold a piece of gasket paper over the stem hole and watch the fuel as I turn on the petcock.This shows fill rate,and level quick and easy before putting on the bowl.
tom

[Gone Looney]

I will try that,I did take the plug out over the top of the needle and pick up on the end of the needle/float assembly and it still didn't flow. Drive a guy to drink more beer

[T. Cotten]

Gone Looney!

You weren't running a rubber-tipped floatvalve, were you?

They can swell, or come unglued, and possibly stick in the seat.

Everything else that can go wrong means overflow, not starvation.

....Cotten

[Gone Looney]

No sir it is the metal tipped valve and it is definitely starving for fuel. Bowl only fills a quarter of the way even with the valve out of the carb

[T. Cotten]

I don't understand, GL...

If the valve is removed, how are you connecting the gasline?

Are you running a filter (other than above the petcocks)?

The fill level is approximately 5/8" of an inch below the top of the bowl deck (7/8" below the top of the bowl casting)
How can you tell anyway?

In the meantime, please make certain the bowl vent doesn't have a mud-dauber in it.

....Cotten

[Gone Looney]

I'm sorry I thought when you said rubber tipped fuel valve I thought you were talking about the needle,I pulled the needle and seat assembly out and remove the needle and put the seat back in and hook the fuel line back up and turn on the fuel. I can see the level by running a clear fuel line and the fuel in the line will sit at the same level as the bowl. The bowl vent is clear.

[T. Cotten]

Yes, GL,..

I was referring to the needle in the valve.

I really do not think the fuel line is a good sight glass when the valve is in the circuit.
The line level should remain above the bowl level if the valve works.

Shouldn't it?

.....Cotten

[Gone Looney]

Cotten you could be correct but I have always run clear line on this bike and the level sits with the float level, maybe therein lies my problem

[T. Cotten]

Cotten you could be correct but I have always run clear line on this bike and the level sits with the float level, maybe therein lies my problem

Its a clue, GL!

If the valve is always open, then the bowl and line should equilibrate.
(Assuming also that other end of the line is open to atmosphere, right?)

But the volume of fluid between the two levels would be a variable that defeats any accurate measurements.
Add more, and both levels should rise.

....Cotten

[Gone Looney]

But once the float shuts off flow isn't that essentially shutting off the vent in the carb therefore shutting off flow from the tank so the line would show the same level as the bowl? I could be thinking of it completely wrong

[Gone Looney]

I'm not trying to argue with you cotten I'm just trying to understand sorry if it comes off that way

[tfburke3]

The only Fuel level is in the tank and the bowl.The fuel line with petcock open is an extension of the tank ,full of fuel from the float valve seat to the tank.Maybe an air bubble in your clear line.
The float valve opens to maintain correct bowl level.The vent is always open.
Tom

[T. Cotten]

Its just like a toilet, GL!

The float drops to let fuel in at the valve, and shuts it off when it refills.

Air has to get in and out as it cycles; Did you stick a toothpick in the vent hole?

....Cotten

[Gone Looney]

I used a 90° pick and it is open,I actually pulled the carb last night and checked everything out,all was clean and clear but the float was cracked. It's made of a foam type material and split right where it attaches to the float arm, still works but I need to replace it before I move on