Standard Procedure - Chrysler Vehicle User Manual

9 - 74 ENGINE 4.0L
ENGINE 4.0L (Continued)
• Any causes for combustion/compression pressure
loss.
(1) Check the coolant level and fill as required. DO
NOT install the radiator cap.
(2) Start and operate the engine until it attains
normal operating temperature, then turn the engine
OFF.
(3) Remove the spark plugs (Refer to 8 - ELEC-
TRICAL/IGNITION
REMOVAL).
(4) Remove the oil filler cap.
(5) Remove the air cleaner.
(6) Calibrate the tester according to the manufac-
turer's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION
AIR ESCAPES THROUGH
THROTTLE BODY
AIR ESCAPES THROUGH
TAILPIPE
AIR ESCAPES THROUGH
RADIATOR
MORE THAN 50% LEAKAGE
FROM ADJACENT CYLINDERS
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLY

STANDARD PROCEDURE

STANDARD PROCEDURE - FORM-IN-PLACE
GASKETS
There are several places where form-in-place gas-
kets are used on the engine. DO NOT use form-in-
place gasket material unless specified.Care must
be taken when applying form-in-place gaskets. Bead
size, continuity and location are of great importance.
Too thin a bead can result in leakage while too much
can result in spill-over. A continuous bead of the
proper width is essential to obtain a leak-free joint.
Two types of form-in-place gasket materials are
used in the engine area (Mopar
Adhesive Sealant and Mopar Gasket Maker). Each
have different properties and cannot be used inter-
changeably.
CONTROL/SPARK PLUG
Intake valve bent, burnt, or not
seated properly
Exhaust valve bent, burnt, or not
seated properly
Head gasket leaking or cracked
cylinder head or block
Head gasket leaking or crack in
cylinder head or block between
adjacent cylinders
Stuck or broken piston rings;
cracked piston; worn rings and/or
cylinder wall
Silicone Rubber
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
(7) Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
- with no more than 25% leakage.
FOR EXAMPLE: At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
Refer to CYLINDER COMBUSTION PRESSURE
LEAKAGE DIAGNOSIS CHART
POSSIBLE CAUSE
MOPAR SILICONE RUBBER ADHESIVE SEALANT
Mopar
mally black in color, is available in 3 ounce tubes.
Moisture in the air causes the sealant material to
cure. This material is normally used on flexible metal
flanges. It has a shelf life of a year and will not prop-
erly cure if over aged. Always inspect the package for
the expiration date before use.
MOPAR GASKET MAKER
Mopar
available in 6 cc tubes. This anaerobic type gasket
material cures in the absence of air when squeezed
between smooth machined metallic surfaces. It will
not cure if left in the uncovered tube. DO NOT use
on flexible metal flanges.
CORRECTION
Inspect valve and valve seat.
Reface or replace, as necessary
Inspect valve and valve seat.
Reface or replace, as necessary
Remove cylinder head and inspect.
Replace defective part
Remove cylinder head and inspect.
Replace gasket, head, or block as
necessary
Inspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
Silicone Rubber Adhesive Sealant, nor-
Gasket Maker, normally red in color, is
TJ