01-20-2016, 12:17 PM
when you rebuild an old carb the adjustment needles on used carbs are mostly usable but have a little surface corrosion from sitting.
always take out and inspect adjustment needles and if possible the needle bore.
if you don't a rough needle will grind away material inside the inlet bore seriously messing up carb fuel inlet ba1ance.
even what looks like a nice smooth needle may be crap.
so careful inspection under magnification is critical. it will reveal damage issues the naked eye may miss.
besides you absulutely should be replacing the o-ring seal in the needle package.
a bad o-ring will leak a huge amount of air and allow the carb to "self-adjust" from vibration.
i've found that a quick wire wheel brush up with a brass wheel followed by light polishing with 000 steel wool cleans them very nicely.
under 7x magnification they are pretty smooth.
i wire brush everything needle point threads and adjustment section.
i then coat them in light oil.
They look a lot nicer than knarley rusted old needles installed in a clean fresh carb.
dave
always take out and inspect adjustment needles and if possible the needle bore.
if you don't a rough needle will grind away material inside the inlet bore seriously messing up carb fuel inlet ba1ance.
even what looks like a nice smooth needle may be crap.
so careful inspection under magnification is critical. it will reveal damage issues the naked eye may miss.
besides you absulutely should be replacing the o-ring seal in the needle package.
a bad o-ring will leak a huge amount of air and allow the carb to "self-adjust" from vibration.
i've found that a quick wire wheel brush up with a brass wheel followed by light polishing with 000 steel wool cleans them very nicely.
under 7x magnification they are pretty smooth.
i wire brush everything needle point threads and adjustment section.
i then coat them in light oil.
They look a lot nicer than knarley rusted old needles installed in a clean fresh carb.
dave