Fuel Flow questions/PROBLEM

[little rocket]

Why does it purr like a kitten when it is gravity fed threw the overflow line from the header tank,I would think if the floats were the problem they would still be a problem when it is getting fuel in any way?
I;m asking because I don't quite get much about how these carbs operate.
THANKS

[jrevens]

Why does it purr like a kitten when it is gravity fed threw the overflow line from the header tank,I would think if the floats were the problem they would still be a problem when it is getting fuel in any way?
I;m asking because I don't quite get much about how these carbs operate.
THANKS

One possible way that could be explained is if the fuel that is supplied by your "return line" all by itself is just adequate or close enough (because of the small line size, etc.) to match the needed flow rate of the engine, and no more. If so, the floats may not matter because the fuel entering the float bowl is being used at close enough to the same rate as it is being supplied. This is what I was trying to say in my previous post as one possible, but not very probable scenario. Highly unlikely, but who knows? The floats could be soaked & defective, and the engine run as you described, if that was happening.



We know it's not the electric pump, because you said it does the same thing when that pump is off.

[little rocket]

jrevens Thanks
I hear what you are saying ,I think the odds of that are like you say unlikely ,but stranger things have happened.I will keep that in mind as I work my way threw the list of things to try.
I thank all you guys for suggestions ,at least I'm learning allot about the fuel system on the 912.


THANKS