On FJ400D-equipped carbureted E-Z-GO ST 350 models, the documented factory carburetor uses a #106 main jet and #52 pilot jet. Confirm the engine before ordering, because earlier carbureted versions can use different jetting and later EFI versions have no carburetor jets.
ST 350 • Main & pilot jet sizes
ST 350 carburetor jet sizes at a glance
Main jet
Earlier EH35C applications: #82; later FJ400D applications: #106
Pilot jet
Earlier EH35C applications: #42; later FJ400D applications: #52
Altitude
Use the exact year and engine parts manual because altitude jets differ by carburetor generation
Before ordering
Identify the engine and carburetor, then read the number stamped on the existing brass jet.
Lean symptoms
Needing choke, surging or load bog can also come from a clogged passage, weak fuel supply or intake leak.
Rich symptoms
Black smoke or plug fouling can also come from a stuck choke, high float level or leaking needle valve.
How to choose the correct E-Z-GO ST 350 jet
ST 350 jetting symptoms
Needs choke to run
Clean the pilot and main circuits and check fuel supply and an intake leak before fitting a larger jet.
Bogs under load
A restricted main jet can cause this, but so can weak pump flow, low bowl fuel level or a blocked filter.
Black smoke / fouled plug
Check choke position, float level and needle sealing before assuming the main jet is too large.
Runs well only at low speed
Main-jet or main-nozzle restriction becomes more likely once the pilot circuit is known to be clear.
Poor idle only
The pilot circuit matters much more than the main jet at idle.
High-altitude operation
Use the model-specific elevation chart where available; do not guess how many jet sizes to reduce.
ST 350 jet specifications
Applies to: Carbureted gasoline version.
Engine: 350 cc EH35C on earlier versions; 401 cc FJ400D on later documented versions.
Carburetor: Engine-generation-specific fixed-float-bowl carburetor.
Main jet: Earlier EH35C applications: #82; later FJ400D applications: #106.
Pilot jet: Earlier EH35C applications: #42; later FJ400D applications: #52.
Altitude: Use the exact year and engine parts manual because altitude jets differ by carburetor generation.
Model-specific note
Do not mix EH35C and FJ400D jet numbers; the carburetors are different even when the vehicle name is similar.
E-Z-GO ST 350 carburetor jet FAQ
What is the E-Z-GO ST 350 main jet size?
Earlier EH35C applications: #82; later FJ400D applications: #106. Do not mix EH35C and FJ400D jet numbers; the carburetors are different even when the vehicle name is similar.
What is the E-Z-GO ST 350 pilot jet size?
Earlier EH35C applications: #42; later FJ400D applications: #52.
Does altitude change the E-Z-GO ST 350 main jet?
Use the exact year and engine parts manual because altitude jets differ by carburetor generation.
Can I install a larger jet in an E-Z-GO ST 350?
Only after confirming the engine, carburetor, altitude and cause of the lean symptom. A clogged passage, intake leak or weak fuel supply should not be corrected with an oversized jet.
How do I identify the correct E-Z-GO ST 350 carburetor jet?
Use the stamped jet number together with the engine code, carburetor ID and model year. Cross-check those identifiers against the matching factory parts or service information.
What is the difference between the main and pilot jet on an E-Z-GO ST 350?
The pilot circuit controls idle and very low-throttle fueling. The main jet becomes dominant as airflow, throttle opening and engine load increase.
Jet sizes can change with engine, carburetor revision, model year and altitude. This page applies to the carbureted gasoline version. Do not drill jets or assume a jet from another model is equivalent. Confirm the engine, carburetor ID and existing jet markings for your exact E-Z-GO ST 350. For manufacturer documentation, visit the official manufacturer website.