3/4" Rochester 4G carburetor pump assembly is designed to withstand today's fuel with alcohol / ethanol. Comes with highest quality pump cup that stands up to today's new fuels.
Note: Not all blue accelerator pump cups on the market are resistant to today's new fuels, don't be mislead by the color, demand the best!
Pump cup/Bore diameter: 3/4"
Over all length (OAL): 2.924"
Stem Length 1.4" (length above from spring retainer to stem tip)
Cup Style: Double lip (ethanol resistant)
Instructions when replacing Rochester accelerator pumps:
It is very important that the accelerator pump bore is completely smooth. Today's fuels with ethanol have less lubrication and demand super smooth pump bore surfaces. Polish pump bore with crocus cloth as required. Rough pump bore surfaces will cause pump cup to stick to bore and tear or dislodge from plunger assembly.
Do not allow carburetor cleaner come in contact with pump assembly.
Coat outer edges of pump cup with a light coating of grease, if pump bore is not submerged in fuel.
Long term vehicle storage:
If vehicle is dormant and fuel bowl is allowed to go dry, pump cup has a much higher chance of sticking to pump bore. If bowl has run dry, fill fuel bowl with fuel before pumping accelerator pump assembly.
Replacement accelerator pump cup: Item #1012A