ORIGINAL: Tired Old Man
Bari1,
Regarding the use of a heavier clunk. Some years back I quit using the clunks that come with the gas takns and now use a Walbro filtered clunk. They are much heavier and serve a dual purpose by also filtering the gas much better than most anything else available.
I used them for a while, but I stopped for two reasons.
First, I like to use a 2 line systrem which means I fill through the supply line. With a filtered clunk any debris gets caught on the engine side of the filter and will instantly end up in the carb screen. Without the filter there is at least a chance that a little debris will not be sucked up.
More important, I had several of those pickups simply clog up for no apparent reason. There was no debris in it, it just quit flowing fuel This caused me several situations where my engine would not start or ran very lean. I was unable to blow air through the pickup line, let alone gas.
I also have heard (but never experienced) that these clunks can shed some of their fibers into the fuel stream, possibly they break down and this is what causes the clogging.
So I ditched it in favor of simplicity and have not had a problem since. I do filter the fuel going into the tank though.
TF