Northern Lights M753 / M753W2 — Injector Removal and Installation
Repair & overhaul · Fuel injectors
For the Northern Lights M753 / M753W2, from the Northern Lights operator's manual.
Applies to: Northern Lights M753, Northern Lights M753W2
Before you start
- Overtightening can damage injector.
- Do not use pry bars to remove injectors.
Procedure
- Clean loose dirt around injectors and fuel lines.
- Relieve high pressure by loosening delivery line flare nuts at each injector.
- Remove delivery lines from injectors and injection pump as an assembly; do not remove spacers; cover openings.
- Remove return line retaining bolts and return line.
- Unscrew and remove injectors; do not use pry bars.
- Discard copper sealing washers; cover holes.
- Install new copper sealing washer in each injector hole.
- Screw in injector and tighten to 43 or 50 ft/lbs (6 to 7 kgm).
- Install return line with new copper sealing washers above and below each connection; tighten retaining bolts to 22 - 30 ft/lbs.
- Install delivery lines loose at injectors for bleeding; pump hand primer to fill lines; tighten at injectors; start and check for leaks.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Injector torque: 43 or 50 ft/lbs (6 to 7 kgm).
- Return line retaining bolts: 22 - 30 ft/lbs.
Full service-parts list: Northern Lights M753 →, Northern Lights M753W2 →
Source: Northern Lights operator'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.