Downloaded from www.Manualslib.com manuals search engine SERVICE DIAGNOSISÐPERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery 1. Charge or replace as necessary.
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to the terminals.
3. Faulty starter. 3. Refer to Group 8A, Battery/
Starter/ Charging System
Diagnostics.
4. Moisture on ignition wires and
distributor cap.4. Wipe wires and cap clean and
dry.
5. Faulty ignition cables. 5. Replace as necessary.
6. Faulty coil or control unit. 6. Refer to Group 8D, Ignition
System.
7. Incorrect spark plug gap. 7. Refer to Group 8D, Ignition
System.
8. Incorrect ignition timing. 8. Refer to Group 8D, Ignition
System.
9. Dirt or water in fuel system. 9. Clean system and replace fuel
filter.
10. Faulty fuel pump, relay or
wiring.10. Refer to Group 14, Fuel System.
ENGINE STALLS OR ROUGH IDLE 1. Idle speed set to low. 1. Refer to Group 14, Fuel System.
2. Idle mixture to lean or to rich. 2. Refer to Group 14, Fuel System.
3. Vacuum leak. 3. Inspect intake manifold and
vacuum hoses, repair or replace as
necessary.
4. Worn or burned distributor rotor. 4. Replace distributor rotor.
5. Incorrect ignition wiring. 5. Install correct wiring.
6. Faulty coil. 6. Refer to Group 8D, Ignition
System.
7. EGR valve leaking. 7. Refer to Group 25, Emissions
Control System.
8. Incorrect cam timing. 8. Refer to Valve Timing in this
section.
9 - 8 4.7L ENGINEDN
DIAGNOSIS AND TESTING (Continued)
Downloaded from www.Manualslib.com manuals search engine DESCRIPTION AND OPERATION
ENGINE
DESCRIPTION
The 5.9 Liter (360 CID) eight-cylinder engine is a
V-Type lightweight, single cam, overhead valve
engine with hydraulic roller tappets. This engine is
designed for unleaded fuel.
The engine lubrication system consists of a rotor
type oil pump and a full flow oil filter.
The cylinders are numbered from front to rear; 1,
3, 5, 7 on the left bank and 2, 4, 6, 8 on the right
bank. The firing order is 1-8-4-3-6-5-7-2 (Fig. 1).
The engine serial number is stamped into a
machined pad located on the left, front corner of the
cylinder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 2).
ENGINE LUBRICATION SYSTEM
DESCRIPTION
A gear-type positive displacement pump (Fig. 3) is
mounted at the underside of the rear main bearing
cap. The pump uses a pick-up tube and screen
assembly to gather engine oil from the oil pan.
OPERATION
The pump draws oil through the screen and inlet
tube from the sump at the rear of the oil pan. The oil
is driven between the drive and idler gears and
pump body, then forced through the outlet to the
block. An oil gallery in the block channels the oil to
the inlet side of the full flow oil filter. After passing
through the filter element, the oil passes from the
center outlet of the filter through an oil gallery that
channels the oil up to the main gallery, which
extends the entire length on the right side of the
block. The oil then goes down to the No. 1 main bear-
ing, back up to the left side of the block, and into the
oil gallery on the left side of the engine.
Galleries extend downward from the main oil gal-
lery to the upper shell of each main bearing. The
crankshaft is drilled internally to pass oil from the
main bearing journals to the connecting rod journals.
Each connecting rod bearing has half a hole in it, oil
passes through the hole when the rods rotate and the
hole lines up, oil is then thrown off as the rod
rotates. This oil throwoff lubricates the camshaft
lobes, distributor drive gear, cylinder walls, and pis-
ton pins.
Fig. 1 Firing Order
Fig. 2 Engine Identification Number
Fig. 3 Positive Displacement Oil PumpÐTypical
1 ± INNER ROTOR AND SHAFT
2 ± BODY
3 ± DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 ± COTTER PIN
5 ± RETAINER CAP
6 ± SPRING
7 ± RELIEF VALVE
8 ± LARGE CHAMFERED EDGE
9 ± BOLT
10 ± COVER
11 ± OUTER ROTOR
9 - 136 5.9L ENGINEDN