Multiquip 99101ZH70900 Main Jet (#90) GX390K1QA2 HC-4221081

The Multiquip 99101ZH70900 Main Jet (#90) GX390K1QA2 HC- is a genuine OEM carburetor jet designed for GX390K1QA2 engine applications. This is a direct-source Multiquip OEM component, meaning it meets the exact specifications of the original part installed at the factory. The #90 sizing is a precise calibration — using the correct jet number is critical to maintaining the proper air-fuel ratio your engine depends on. Fits equipment powered by the GX390K1QA2 engine configuration; confirm your model code before ordering to ensure an exact match.

Key Features

• OEM-Calibrated Fuel Metering Orifice — The #90 jet size is factory-specified for the GX390K1QA2 engine, ensuring the carburetor delivers the correct fuel flow for consistent combustion.
• Drop-In Carburetor Replacement — Threads directly into the carburetor body of GX390K1QA2-equipped machines with no modification to the carb assembly needed.
• GX390K1QA2 Engine Fitment — Sourced specifically for GX390K1QA2 engine-powered Multiquip equipment; always verify your engine model code against 99101ZH70900 before purchase.
• Protects Engine from Rich or Lean Run Conditions — A worn or incorrect main jet causes rough idle, poor throttle response, and potential engine damage; replacing with the correct OEM jet restores proper fuel delivery.
• Genuine Multiquip OEM Quality — Manufactured to the same material and dimensional tolerances as the original, so the orifice diameter holds calibration under sustained engine operating temperatures.

The main jet is the primary fuel-metering component inside a float-style carburetor. It is a precisely sized orifice that controls how much fuel is drawn into the engine at mid-to-full throttle, and the jet number — in this case #90 — refers to the bore diameter calibrated for that specific engine's fuel demand. When a main jet wears, clogs, or is replaced with an incorrect size, the engine runs either too rich or too lean, resulting in loss of power, excessive fuel consumption, fouled spark plugs, or potential engine damage from heat. Replacing a failed or suspect main jet with the correct OEM part, part number 99101ZH70900, restores the precise fuel metering the GX390K1QA2 engine was designed to operate on.

Part Details

Compatibility & Fitment

Verify Before You Order

Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.

Why Buy From DHS Equipment

Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.

Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.