Lincoln Nautilus: Engine System - General Information / Valve Train Analysis - Gasoline. General Procedures
Valve Train Analysis - Engine Off, Valve Cover Removed
NOTE:
The following component inspections are used to diagnose valve train concerns.
-
Check for damaged or severely worn parts and correct assembly.
Valve Train Analysis - Camshaft Lobe Lift
-
Remove the spark plugs.
For additional information, refer to: Spark Plugs (303-07A)
.
For additional information, refer to: Spark Plugs (303-07B)
.
For additional information, refer to: Spark Plugs (303-07C)
.
For additional information, refer to: Spark Plugs (303-07D)
.
For additional information, refer to: Spark Plugs (303-07E)
.
-
Install the Dial Indicator Gauge with Holding Fixture so
the rounded tip of the dial indicator is on top of the camshaft lobe
and on the same plane as the valve tappet.
-
Rotate the crankshaft using a breaker bar and socket
attached to the crankshaft pulley retainer bolt. Rotate the crankshaft
until the base circle of the camshaft lobe is reached.
-
Zero the dial indicator. Continue to rotate the
crankshaft until the high-lift point of the camshaft lobe is in the
fully raised position (highest indicator reading).
-
To check the accuracy of the original dial indicator
reading, continue to rotate crankshaft until the base circle is reached.
The indicator reading should be zero. If zero reading is not obtained,
repeat Steps 2 through 5.
-
If the lift on any lobe is below specified service
limits, install a new camshaft and camshaft roller followers or valve
tappets.
-
Install the spark plugs.
For additional information, refer to: Spark Plugs (303-07A)
.
For additional information, refer to: Spark Plugs (303-07B)
.
For additional information, refer to: Spark Plugs (303-07C)
.
For additional information, refer to: Spark Plugs (303-07D)
.
For additional information, refer to: Spark Plugs (303-07E)
.
Check
NOTE:
Refer to the appropriate Section 303-01 for the specification.
Measure the diameter of each intake and exhaust valve
stem at the points shown...
Other information:
Check
NOTE:
Refer to the appropriate Section 303-01 for the specification.
NOTE:
Crankshaft main bearing journals must be within specifications before checking journal clearance.
Remove the crankshaft main bearing cap and crankshaft main bearing.
Position a piece of Plastigage across the crankshaft main bearing surface.
NOTE:
Do not turn..
Preliminary Inspection
Road test the vehicle.
If any suspension alignment or ride height concerns are present, REFER to Symptom Chart: Suspension System.
Verify the customer concern by carrying out a road test
on a smooth road. If any vibrations are present, REFER to Symptom Chart:
NVH .
Inspect the tires.
Check the tire pressures with all normal loads in the ..