Specifications

Instructions 77-9045 Bacharach, Inc. Page 3-1
CD3 AUDIT KIT DETROIT DIESEL INJECTORS
3.0 DETROIT DIESEL (DD)
ENGINE INJECTORS
All the procedures described in this section are
necessary to ensure accurate testing of Diesel
Technology Corp. injectors used in Detroit Diesel
engines (commonly refered to as DD injectors).
3.1 CALIBRATOR RPM TEST
This test ensures that the injectors are driven at
the correct speed. Because the main motor is
synchronous, the speed of the camshaft depends
only on the incoming power frequency and the belt
rating. As long as the frequency is held to 60 Hz (or
50 Hz, depending on the motor used), the speed will
fall within the prescribed range. If an injector is
driven at a lower than prescribed speed, its flow
output will increase because the absolute time for
filling is increased.
Equipment Required
• Hand held digital tachometer, optical preferred
• Screwdriver (small stubby)
3.1.1 Using a Photo-Electric Tachometer
Set-up
1. Switch circuit breaker OFF.
2. Open the pulley cover.
NOTE: Older units use a sliding pulley
cover, which should be opened ½ inch.
3. Attach a small piece of reflective tape (usually
supplied with the tachometer) to the front
flywheel face so that it can be seen through the
perforated window.
NOTE: The white painted strip on the
flywheel can be used instead of the tape.
The painted strip can be viewed through
the perforated window.
4. Close pulley cover.
5. Turn circuit breaker on side of calibrator ON.
6. Press the START button.