General Motors 4.3L GM Engine — Fuel Mixer Removal/Installation
Repair & overhaul · Air fuel mixer
For the General Motors 4.3L GM Engine, from the General Motors service manual.
Before you start
- The mixer should not be disassembled or rebuilt - replace with OEM part if faulty.
Procedure
- Relieve the LPG fuel system pressure (refer to LPG Fuel System Pressure Relief).
- Disconnect the negative battery cable.
- Remove the air intake duct.
- Remove the retaining pin holding the fuel hose fitting and remove fuel hose.
- Remove 3/8" hose from 90 degree brass fitting.
- Remove the four screws under the Adapter Mounting Bracket.
- Remove and discard the mixer to throttle body assembly O-ring.
- Installation: place new O-ring on throttle body, install Mixer, secure with four retaining screws and torque to 9 N·m (80 in. lb.).
- Install fuel hose fitting into Mixer and hold with retaining pin; install air intake duct and 3/8" hose.
- Reconnect negative battery cable, open LPG tank manual shut-off valve.
- Turn ignition ON ~30 seconds then OFF; leak check at each serviced fitting.
- Start vehicle, leak check, and test drive at all throttle ranges.
Tools required
- Liquid or electronic leak detector Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Mixer retaining screws 9 N·m (80 in. lb.)
Source: General Motors service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.