Celect (Cummins Electronic Control) & Celect Plus Injector Adjustment

Celect (Cummins Electronic Control) & Celect Plus Injector
Adjustment
Name: ________________________________
Date: ________________________________
Cummins CELECT and CELECT Plus system injectors are used on Cummins
electronically controlled engines between 1990 and 2001 in L, M & N series engines.
Injector adjustment is accomplished by applying the correct preload to the timing plunger
of the injector when the engine is at 45-degrees before TDC.
1. Injector hold-down bolts should
have been previously torqued down to
45-Ft/lbs – verify proper hold-down
torque.
Rotate engine to valve set marks on
accessory drive pulley for cylinder you
will adjust valves and injectors.

2. Identify the cylinder and correct rocker arms for adjustment.
• There are three housings on an N-14.
• The intake levers are located near the center of the rocker housings and the
exhaust levers closest to the outside of each housing.
• Adjust both valves per specification on engine data plate.
3. The injectors are adjusted at the same time
as the valves. Use the accompanying chart to
determine which cylinder to adjust.
Both valves must be closed on the cylinder
you are adjusting the valves. The rocker
levers will move from side to side.
List the companion cylinder for each of the following cylinders:
1- ___ 2 -___ 3-__- 4-___ 5-___ 6-___
What valve or injectors can be adjusted in each of the following accessory drive
positions
A _______ B______ C______
4. Injectors are adjusted using the following method:
• Bottom the injector plunger out three or four times to remove fuel beneath the
timing plunger by tightening and loosening the injector adjustment screw. Do not
tighten more than 25 in-lbs.
• Tighten the adjusting screw to 25 in-lbs.
• Back-out adjusting screw 2 flats or 120 degrees.
• Lock the lock nut.
5. Reinstall engine brake housings and torque to 75 ft-lbs

6. Adjust engine brakes using the dial indicator method.
• Identify the correct slave piston to adjust. All engine brakes are adjusted at the
same time the exhaust valves should be adjusted. So follow the valve and injector
chart again to obtain correct engine position.
• Move slave piston down until it just contacts the exhaust valve bridge.
• Zero-in the dial indicator.
• Back-out the dial indicator to the specification located on the side of the brake
housing.