Bing 27 Pilot Circuit

[Steve Minor]

Got problems with the pilot circuit on a 72 Six Day project. I might add that I installed all new jets and new #4needle, set on third slot from the top

First: Currently I'm running a new #45 pilot jet and the air screw adjustment indicates it's still too lean. The RPMs rise as I turn the screw in and the motor runs it's best at about 1/2 turn out. It still has a slight hesitation when I "blip" the throttle.

Second: The slide has a pretty big "dimple" at the throttle speed adjustment screw location. Any way to repair it or should I just replace it. Could a worn slide effect the pilot circuit problem?

Steve Minor

[Kip Kern]

Look at the underside of the enricher circuit plunger 1st.  Most problems start there.  Some folks call it a choke circuit. As long as the slide doesn't have a deep smiley in it, I wouldn't worry about it.  The pilot jet is for the starting circuit, if it starts good, don't mess with it.  I would look at the needle jet diameter, never ruined a piston running rich!

[Steve Minor]

Thanks Kip. Just for the record, I'm running a #45 Idle Jet, 276 Needle jet, #4 Needle on 3rd slot down, a #140 Main and a new Plunger assembly from Bing. All internal parts are new.

Steve Minor