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BF 9.9 Carburator Cleaning Question

J

James1671

New member
Hello , I recently aquired a 2002 Honda 9.9 that had been in storage for some years. Followed the steps on carb cleaning from here (thanks everyone) however there is one section / part in the float chamber I cannot get clarity on. Near the plunger area there is a hole that has a square looking brass piece inside , it appears this chamber/channel leads to under the plunger piston. Does this need to come out to clean the passage? if so how? Trying to attach pics. Thanks in advance. James
 
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There are two passageways under the accelerator pump piston. One is the feed that brings fuel from the float chamber. It's made with a stainless steel check ball that is for trapping the fuel under the piston so that it will not return to the fuel chamber. It's important that the passage is clear from bowl to piston chamber. The check ball on these usually comes loose and falls out. But don't be concerned about that. Just make sure the passageway is clean.

The other passage is where the piston forces gas out of the pump chamber and through a passage that leads to a little brass tube that juts out into the inlet of the venturi at the front of the carb. The tiny tube has a tiny orifice on its end that fuel from the accelerator pump is supposed to shoot out of during hard throttle application. That tiny orifice gets plugged easily and can require some persistent flushing and back flushing to get it cleaned. If that orifice isn't kept clean and open, the engine will not run well.

The accelerator pumps on these carbs are relatively worthless and don't make much of a difference whether brand new or if you remove the piston and throw it away. That's why I said don't worry about the loose or missing check ball.

BUT...those passages and and the tiny orifice at the end of the brass tube MUST be kept clean for the engine to develop full power.
 
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