Diesel Engine - Dynamic Timing

Bulletin No. T 84-68
File In Group 6A
Number 60
Date Apr. '84


SUBJECT: DIESEL ENGINE DYNAMIC TIMING

MODELS AFFECTED: ALL MODELS EQUIPPED WITH A 4.3L OR 5.7L DIESEL


Timing specifications for the 5.7L and 4.3L diesel engines are based upon use of a luminosity timing method available from many suppliers, such as Snap-On, Kent-Moore, Owatonna and Sun. Any other type of device that measures something other than luminosity (such as pressure impulse) will not correlate with the specifications and should not be used.

The Kent-Moore dynamic timing meter has two pick-ups. One pick-up measures the pressure impulse in the injection pipe and the other pick-up measures luminosity through a probe in the glow plug hole. When using this equipment, be sure to use the luminosity pick-up rather than the impulse pick-up.

Timing specifications are located on the "vehicle emissions control information" label for 1983 and 1984 vehicles. Past model (1978-1982) specifications are reprinted below from Serviceman Bulletin I-82-87 for your reference.

Low Altitude High Altitude
Counties Counties

Year Engine Timing RPM Timing RPM

1978 5.7L -4 1/2~ 1200 -5 1/2~ 1200

1979 5.7L -4 1/2~ 1200 -5 1/2~ 1200

1980 5.7L -4 1/2~ 1200 -5 1/2~ 1200

1981 5.7L -4~ 1200 -5~ 1200

1982 5.7L Low Altitude -4~ 1250 -5~ 1250
Emissions Package

5.7L High Altitude -3~ 1250 -4~ 1250
Emissions Package