Chrysler Dodge Caravan 2002 Manual page 1213

9 - 12 ENGINE 2.4L
ENGINE 2.4L (Continued)
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
Only use the following for cleaning gasket surfaces:
• Solvent or a commercially available gasket
remover
• Plastic or wood scraper (Fig. 3)
• Drill motor with 3M Roloc™ Bristle Disc (white
or yellow) (Fig. 3)
CAUTION: Excessive pressure or high RPM (beyond
the recommended speed), can damage the sealing
surfaces. The mild (white, 120 grit) bristle disc is
recommended. If necessary, the medium (yellow, 80
grit) bristle disc may be used on cast iron surfaces
with care.
Fig. 3 Proper Tool Usage For Surface Preparation
1 - ABRASIVE PAD
2 - 3M ROLOC™ BRISTLE DISC
3 - PLASTIC/WOOD SCRAPER
STANDARD PROCEDURE - MEASURING
BEARING CLEARANCE USING PLASTIGAGE
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 4). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
Fig. 4 Plastigage Placed in Lower Shell—Typical
1 - PLASTIGAGE
(3) Remove the bearing cap and compare the
width of the flattened Plastigage with the metric
scale provided on the package. Locate the band clos-
est to the same width. This band shows the amount
of clearance in thousandths of a millimeter. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Compare clearance measurements to specs found in
engine specifications (Refer to 9 - ENGINE - SPECI-
FICATIONS). Plastigage generally is accompa-
nied by two scales. One scale is in inches, the
other is a metric scale.
NOTE: Plastigage is available in a variety of clear-
ance ranges. Use the most appropriate range for
the specifications you are checking.
(4) Install the proper crankshaft bearings to
achieve the specified bearing clearances.
REMOVAL - ENGINE ASSEMBLY
(1) Perform fuel pressure release procedure (Refer
to 14 - FUEL SYSTEM/FUEL DELIVERY - STAN-
DARD PROCEDURE)
(2) Disconnect battery negative cable.
(3) Remove air cleaner housing and inlet tube.
(4) Disconnect the fuel line from fuel rail. (Refer to
14 - FUEL SYSTEM/FUEL DELIVERY/FUEL LINES
- STANDARD PROCEDURE)
(5) Disconnect all vacuum hoses.
(6) Drain cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(7) Remove radiator fans. (Refer to 7 - COOLING/
ENGINE/RADIATOR FAN - REMOVAL)
(8) Remove radiator upper and lower hoses.
RS