Weber Idle Jet 0.45mm - Part Number 74403-045
This genuine Weber idle jet features a precise 0.45mm calibration and is designed for use in a wide range of Weber carburetor models. The jet is manufactured in Italy to original Weber specifications and has been factory flow-tested to ensure optimal performance.
Function
Idle jets supply fuel at low engine speeds and part throttle until the air speed increases sufficiently to start drawing fuel from the main circuit. This typically occurs up to 3000rpm depending on the engine and venturi size used. The actual idle mixture can be adjusted with the idle mixture screw, while the progression holes play an important role during the transition stage from the idle circuit to the main circuit.
Compatible Weber Carburetor Models
This idle jet (part number 74403) is compatible with numerous Weber carburetor series including:
- ADC, ADF, ADFA, ADL, ADLA, ADLD
- DAC, DAR, DARA, DAT, DATA, DATR, DATRA
- DCOF, DFAV, DFC, DFE, DFM, DFT, DFTA, DFTH, DFTM, DFV
- DGAR, DGAS, DGAV, DGF, DGMS, DGS, DGV
- DHS, DHSA, DHTA, DIC, DICA
- DMS, DMSA, DMTC, DMTE, DMTL, DMTR, DMTRA, DMTT
- DPS, DRT, DRTC, DRTM, DSTA
- IBA, ICB, ICEV, ICR, IDAP, IDT
- TL, TLA, TLC, TLF, 3 Barrel Carburettors
Features
- Genuine Weber part manufactured in Italy
- Factory flow-tested for accuracy
- Size calibration engraved directly into the jet
- Precision-engineered 0.45mm opening
- Direct replacement for original equipment
Technical Notes
If the idle mixture screw requires more than 3 turns out, the idle jet may be too small for the application. Larger venturi often require larger idle jets to compensate for lower air speeds at low RPM and part throttle openings. Professional installation and calibration is recommended for optimal carburetor performance.