Mityvac MV5535 Digital Diesel Compression Test Kit - Manual (Page 6)

Page Number - 6 Form 823637
UNIT/OFF button. Press and hold the CLEAR button
for at least three (3) seconds to clear the memory and
return the current cylinder indication to cylinder 1.
9. Check to see that the proper unit of measure, PSI, BAR,
or KPA, is displayed in the lower left corner of the LCD.
If not, press the ON/UNIT/OFF button until the desired
unit of measure is indicated.
10. Connect the tester to the glow plug adapter installed in
cylinder 1.
11. While watching the gauge, crank the engine and count
the compression strokes by listening to one of the adja-
cent cylinders. Watch for the pressure to peak around
6 to 10 strokes, then stop cranking. Make note of the
number of strokes required to reach peak compression.
12. Press the pressure relief button on the side of the tester
to release the pressure.
13. Disconnect the gauge and remove the glow plug
adapter.
14. Install the glow plug adapter in cylinder 2, and recon-
nect the tester.
15. Advance the cylinder number shown on the tester LCD
to 2 by pressing the CYLINDER button.
16. Repeat the compression test on cylinder 2 and all
remaining cylinders. Be sure to crank the engine the
same number of strokes for each cylinder, and to ad-
vance the cylinder number shown on the tester.
17. After completing the test on all cylinders, remove the
tester and adapter, and replace the glow plugs.
18. The peak compression value for each cylinder can be
viewed by scrolling through the cylinders using the CYL-
INDER button.
Testing with Injector Adapter
Prior to starting a compression test, consult manufacturer’s
specifications and/or appropriate service manual to deter-
mine whether the test should be performed while cranking
or running. Familiarize yourself with the proper specifica-
tions and any unique testing procedures, and follow the
recommended procedures for removing and installing the
injectors.
1. Put the vehicle in neutral or park, and set the parking
brake.
2. Thoroughly clean the area around each injector to elimi-
nate any chance of dirt or contamination entering the
engine.
3. Run the engine to warm it to normal operating tempera-
ture.
4. If the test is to be performed while cranking, ensure the
battery has a full charge and/or connect a charger or
auxiliary battery.
5. Follow the manufacturer’s recommended procedure for
disabling the fuel supply and removing the injector(s).
6. Select the appropriate injector adapter and install it into
cylinder 1.
7. Turn on the compression tester by pressing the ON/
UNIT/OFF button. Press and hold the CLEAR button
for at least three (3) seconds to clear the memory and
return the current cylinder indication to cylinder 1.
8. Check to see that the proper unit of measure, PSI, BAR,
or KPA, is displayed in the lower left corner of the LCD.
If not, press the ON/UNIT/OFF button until the desired
unit of measure is indicated.
9. Connect the tester to the injector adapter installed in
cylinder 1.
10. While watching the gauge, crank or run the engine as
specified by the manufacturer. If cranking, count the
compression strokes by listening to one of the adjacent
cylinders. Watch for the pressure to peak around 6 to
10 strokes, then stop cranking. If running the engine,
note the length of running time until maximum pressure
is reached.
11. Press the pressure relief button on the side of the tester
to release the pressure.
12. Disconnect the gauge and remove the injector adapter.
If required, reinstall the injector before proceeding.
13. Install the injector adapter in cylinder 2, and reconnect
the tester.
14. Advance the cylinder number shown on the tester LCD
to 2 by pressing the CYLINDER button.
15. Repeat the compression test on cylinder 2 and all
remaining cylinders. Be sure to crank the engine the
same number of strokes for each cylinder, or to run the
engine for the same amount of time, and to advance the
cylinder number shown on the tester.
16. After completing the test on all cylinders, remove the
tester and adapter, and reinstall injector(s).
17. The peak compression value for each cylinder can be
viewed by scrolling through the cylinders using the
CYLINDER button.
18. Follow manufacturer’s instructions for analyzing the
results.