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· Registered
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Discussion Starter · #1 ·
Hey guys back again.....I think my float was stuck or completely off level when I got gas into my crankcase last month.
My engine model # is 303700. It shows 303777, but I can only find info. using zeros at the end.
My question is what is the inlet ( smaller one) next to the inlet the fuel hose attaches to? This never had anything attached to it, and my neighbor who leveled my float and seated the needle valve, said that if you put a hose on the inlet to the carb and fill the bowl up w/gas through the hose, there should be no fuel coming out of anywhere on the carb....except I guess if you filled it too full and it backed up through the hose of course.
So he was filling it and gas came out of the smaller inlet next to the main fuel inlet. Like I said I never had an additional hose to hook to this inlet, so is this a vent or something? Does my carb have some kind of spring in it that acts like a vacuum when the bowl gets full? I know it is gravity fed.
Simplicity 1693379 16hp Vanguard V twin. I can't find a new carb online other than B&S and that is 250.00! Really don't want to go there.:help:

· Administrator
6,322 Posts
I found what looks to be the repair manual for that engine:

page 79 starts the section with several carbs that are used on them.

Sounds like probably a bowl vent. As the level of gas varies slightly in the float bowl it allows internal air pressure to equalize with the outside (atmospheric) air pressure in an effort to stabilize the air fuel mixture produced by the carb. I think in some applications where fuel leaking out of the vent could cause a safety issue (such as dripping on a muffler) they hook a hose to it so it drains in a safer area. (On my Honda generator they vent the bowl using a tube to the outside bottom of the enclosed cabinet.) But that is just my own theory as to why they do it sometimes and others not.
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