Cummins/Onan GTA38 / GTA50 — Sparkplug Installation
Maintenance · Ignition system
For the Cummins/Onan GTA38 / GTA50, from the Cummins/Onan owner's manual.
Applies to: Cummins/Onan GTA38 engine, Cummins/Onan GTA50 engine
Before you start
- Mechanical over-tightening can damage the sparkplug and cylinder head.
- Never lubricate the threads of the sparkplug.
Procedure
- Make sure porcelain is clean; do not touch the porcelain area.
- Thread plug in by hand using extension and magnetic socket S971KA.
- Turn clockwise to tighten.
- Torque to 35 to 41 Nm [26 to 30 ft-lb].
- Apply dielectric grease inside and outside the sparkplug boot.
- Press boot down until a snap is felt.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 35 to 41 Nm [26 to 30 ft-lb]
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.