Universal QMB139 50cc Carburetor w/ Vacuum Port: 19mm

QMB139 Type-4 19mm Carburetor with Accelerator Pump and Vacuum Port

Restore your scooter’s fuel efficiency and smooth idling with the Universal Parts Type-4 Carburetor. Specifically designed for 50cc 4-stroke QMB139 engines, this 19mm intake carburetor features a dedicated vacuum port for charcoal canister hook-up, ensuring your emissions system functions exactly as the factory intended. Whether you are dealing with a clogged pilot jet or a leaking float bowl, this complete assembly offers a cost-effective, "bolt-on" solution to get your scooter back on the road.

Technical Performance Features

• Emissions Ready: Includes the integrated charcoal canister hook-up required for compliance on modern street-legal 49cc/50cc scooters.
• Enhanced Throttle Response: Equipped with a built-in accelerator pump to eliminate "flat spots" and provide instant fuel delivery during initial acceleration.
• Cold-Start Reliability: Features a pre-installed 2-pin male electric choke (auto-by-starter) for effortless starting in all weather conditions.
• Precision Venturi: The 19mm inner diameter is optimized for 50cc displacement, providing the ideal air-fuel mixture for standard and mildly tuned engines.

Comprehensive Fitment Guide

This carburetor is a standard fit for 50cc 4-Stroke (QMB139/1P39QMB) scooters featuring evaporative emission systems:

Technical Specifications

• Intake Inner Diameter: 19mm
• Air Filter Mount Outer Diameter: 38mm
• Choke Type: Electric (2-Pin Male Plug)
• Special Feature: Accelerator Pump & Canister Port

Mechanic's Note: If your scooter has a charcoal canister (common on newer models), using a carburetor without the proper hook-up can cause vacuum leaks and poor performance.

Installation Tip: Before installing, verify your Intake Manifold isn't cracked, as air leaks there will make any new carb impossible to tune.

Pro Tip: Always ensure your Fuel Filter is clean to prevent immediate clogging of the new jets!

SKU: 151-233
Vendor: Universal Parts

This product is not intended for use on public roads or land.