TROUBLESHOOTING
Page 81
The engine oil temperature must be within normal
operating range when the test is performed.
If the oil pressure remains low, correct the engine
problem as described under OIL PRESSURE
DROPPING BELOW MINIMUM REQUIRED FOR
ENGINE BRAKE OPERATION in the
Troubleshooting Guide included in this section.
OIL PRESSURE REQUIREMENTS
INSPECTION OF ENGINE BRAKE
COMPONENTS
If oil pressure at the brake housings is sufficient
for brake operation, then inspect the engine
brake components for excess wear, damage or
malfunctioning conditions described in this
section.
1. Start the engine and allow it to idle for a few
minutes. Check for oil leakage at the oil
supply screw, solenoid valve and housing
pipe plugs. Oil leakage can result in weak,
intermittent or no braking. If leakage is
found, shut down the engine and replace
seals or repair as needed.
When the engine is shut down for several
minutes, the oil in the brake housings will
bleed down. To refill the brake housings for
immediate operation, depress the solenoid
cap (pin) several times to fill the housing
with engine oil.
2. With the engine brake on, observe that the
master pistons are moving out of the
housing and making contact with the
exhaust rocker spherical nuts. They should
move in and out freely. If they do not, shut
down the engine and check the control
valves and control valve springs for those
cylinders.
Remove control valve retaining components
carefully to avoid personal injury. Control
valve retaining components are under load
from the control valve springs.
3. The control valve must move freely in the
bore. If not, remove it and replace with a
new control valve.
If the bore is damaged (scored), use a light
crocus cloth to smooth the bore. Clean the bore
and install a new control valve. If severe damage
to the bore is found, replace the housing.
4. Replace any broken springs.
5. If the control valves and springs are OK and
the master and slave pistons were observed
not to be operating, remove the housings for
inspection.
Visually inspect the following:
Master piston springs — If broken or worn,
replace the springs.
Master pistons — Pistons must move freely
in the bore. Check the hard facing on the
master piston for damage; this is the area
that contacts the spherical nut.
Spherical nut rocker adjusting screw —
Check the spherical nut for excessive wear.
If a depression of 0.005 inch or deeper is
found in the top of the spherical nut or if the
pattern of wipe extends beyond the edge of
the nut, replace the spherical nut. Also,
replace the companion master piston. The
spherical end of the rocker adjusting screw
should be checked for proper contour and
smooth appearance. Replace if necessary.
Internal check valve components — If the
housing contains internal check valve
components and a hollow oil supply screw,
remove the check valve components (ball,
spring, retaining ring and washer) from the
housing and replace the hollow oil supply
screw with the current-production screw
containing an integral check valve.
Oil supply screws — Check for damage and
replace if necessary.
E-Tech™ Engine with J-Tech™ Engine Brake
Engine rpm 2100 — 40 psi (2.8 bar)
Engine rpm 1700 — 35 psi (2.4 bar)*
Engine rpm 1500 — 30 psi (2.0 bar)*
Engine rpm 1300 — 30 psi (2.0 bar)*
Engine rpm 1100 — 30 psi (2.0 bar)*
* Specified pressures with engine at normal operating
temperatures
5_106_00.bk Page 81 Friday, August 4, 2000 11:17 AM
BDC for engine manuals and specs
