realmccoy / JimB : This overused term "hardstarting" covers such a wide variety of troubles and problems its necessary to determine under exactly what conditions the hard starting occurs. Its important to know: 1. hard to start all the time? 2. only when cold? 3. only when hot? (describe how hot?) 4. only after the engine has been turned off for a while? 5. once started, is the hard starting condition accompanied by missing, pinging, knocking,or a failure to keep running? 6. does the engine crank slowly, while trying to start? 7. has engine been tuned/plugs changed recently? Checked timing? 8. Have you rebuilt the carb recently? From the sound of things I feel you have been checking things out, but you'll have to dig a little deeper. You should not have to move the throttle, or use fluid to start. If float bowl is full and vacuum passages are clear, should start. Did you check fuel pump delivery? Should be between 2 to 5 lbs of pressure (with 2/2.5 being ideal) and 3/4 to 1 pint per/min to the carb. Sounds like you have a lean mixture as you have to add fuel/fluid to start. Check manifold bolts, and all carb screws you may have a vacuum leak. Also check gaskets at air horn to float body, and float body to throttle body for leaks and tighten. Check carb to manifold gasket & tighten. If you have recently rebuilt the carb you may have put one of the gaskets in backwards/upsidedown. They only go in one direction. If you have a vacuum leak the float will not vent/fill to the correct level and idle mix will be too lean. Float needle/seat can be dirty or worn. Check float level? Check float bouyancy, does it leak? Float hinge maybe binding or broken? Also check fuel lines to carb, fuel filter for leaks or blockage. Something is restricting the fuel to the float bowl and/or evaporating it, (vaporlock) or a vacuum vent is plugged. If you use a vacuum gauge and you attach below the carb at carb base it will not tell you if you have a vac leak in the carb body itself, as it can be internal. The power valve/power piston high side of the carb does not seem to be the problem. Your troble is in the low speed/idle system and/or fuel delivery. You need to check this stuff out. Repost your findings and be safe!!! :confused:
