Universal QMB139 50cc Carburetor Intake Insulator Spacer

QMB139 50cc Carburetor Insulator

Protect your fuel system and ensure a stable idle with the Universal Parts Carburetor Insulator. Specifically designed for the 50cc 4-stroke QMB139 (GY50) engine platform, this high-density plastic spacer sits between the intake manifold and the cylinder head. Its primary function is to act as a thermal barrier, preventing extreme engine heat from reaching the carburetor, which can cause fuel boiling, "vapor lock," and inconsistent performance.

Technical Performance Features

• Thermal Isolation: Crafted from heat-resistant composite material that effectively blocks heat transfer, keeping your carburetor cool for more reliable fuel atomization.
• Airtight Sealing Surface: Features precision-flat mating surfaces to eliminate vacuum leaks, which are the leading cause of "hanging idles" and lean-run conditions on 50cc scooters.
• Standard 45mm Fitment: Engineered with the industry-standard 45mm bolt-hole spacing, ensuring a drop-in fit for almost all Chinese 50cc 4-stroke intake manifolds.
• Durable Composite Construction: Unlike cheap plastic alternatives, this insulator is designed to resist warping and cracking under the constant heat-cycling of an air-cooled engine.

Comprehensive Fitment Guide

This insulator is a standard replacement part for the 50cc 4-Stroke (QMB139/GY6 50) engine found in:

Technical Specifications

• Center Hole Diameter: 16mm
• Bolt Hole Spacing: 45mm (Center-to-Center)
• Material: Heat-Resistant Phenolic/Plastic Composite
• Compatibility: 50cc 4-Stroke QMB139 Engines

Mechanic's Note: If your scooter runs great when cold but starts stumbling or dying once the engine gets hot, this insulator may be cracked or missing. Pro Tip: This insulator requires a Paper Gasket on both sides to create a true vacuum seal. Always check your Intake Manifold for cracks while you have this assembly apart.

SKU: 151-7
Vendor: Universal Parts