Function of primer bulb

[swist]

In another thread, a knowledgeable memeber wrote<br /><br />"the fuel bulb needs to be squeezed on every cold start up and also after long shutdowns during the day"<br /><br />My bulb is located behind a transom hatch which requires the rear seat to be moved to open. Consequently I never touch the thing except at the beginning of the season. Never had a starting problem. Aren't these things redundant with large outboards (mine a Yam 225) with decent fuel pumps? You don't see them on cars. I always associated them with little engines with little portable tanks. In fact when I got my first large hp engine, I was surprised to see one. Any logic to this?

 

[jim dozier]

Re: Function of primer bulb

I don't know if the fuel bulb is as necessary on a fuel injected engine as it is on a carbed engine. Most of the fuel pumps on carbed 2-strokes are small displacement pulse/diaphragm pumps which don't move as much fuel as the automotive types. The purpose of the bulb is to save your starter and battery by making sure the carb bowls are filled at startup. I suppose a lot depends on the engine-tank setup, whether you've tilted the engines, the carb float adjustment, the length of fuel line between the tank and engine and the relative heights, etc. etc. My original point was simply that it should be accesible.