TM 5-3805-281-24-2
Fuel System
INJECTION NOZZLE OPENING PRESSURE
SPECIFICATIONS
A new nozzle or a used nozzle with a new spring (A),
should open at approximately the following pressures. A
used nozzle that has been rebuilt with a new spring
and/or valve should be reset to same pressures as a new
nozzle. New nozzle opening pressures are:
New Injection Nozzle (All Tip Sizes)--Specification
Opening Pressure .................................. 29 000 kPa (290 bar) (4200 psi)
Injection Nozzle Spring and Pressure Adjusting Shims
minimum
On nozzles which have been in service, spring and spring
seat (B) will have taken a normal set. In this case,
opening pressure is satisfactory if it meets or exceeds
used nozzle minimum opening pressure given below, but
does not exceed new opening pressure given above.
Used nozzle minimum opening pressures are:
Used Injection Nozzle (All Tip Sizes)--Specification
Opening Pressure .................................. 26 200 kPa (262 bar) (3800 psi)
minimum
IMPORTANT: ALWAYS use John Deere nozzle
adjusting shims which are specially
hardened. Other shims will not be
satisfactory.
Shims (C) of different thicknesses are available for
changing opening pressure adjustment. Each 0.05 mm
(0.002 in.) of shim thickness changes opening pressure
approximately 700 kPa (7 bar) (100 psi).
If nozzle opening pressures are not correct, disassemble
injection nozzles (as described in this group) and change
shims until nozzles open at proper new nozzle pressure
given above.
The difference in nozzle opening pressures between
cylinders in an engine should not exceed 350 kPa
(3.5 bar) (50 psi).
RG,RG34710,1305
1923OCT971/1
