Cummins/Onan GTA14 / GTA14 qi 20 NA — Spark Plug Removal
Maintenance
For the Cummins/Onan GTA14 / GTA14 qi 20 NA, from the Cummins/Onan owner's manual.
Applies to: Cummins/Onan GTA14 qi 20 NA, Cummins/Onan GTA14 engine
Procedure
- Disconnect wire assembly from ignition coil end first, then spark plug end.
- Remove rubber insert from spark plug socket.
- Loosen spark plug counter-clockwise using 15.875 mm (5/8 in.) deep-well rubber insert socket.
- Continue turning until threads disengage.
- Lift spark plug out; mark or tag with cylinder number.
- Inspect plug wires, extenders and connections.
Tools required
- 15.875 mm (5/8 in.) deep-well rubber insert spark plug socket Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Full service-parts list: Cummins/Onan GTA14 qi 20 NA →
Source: Cummins/Onan owner's 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.