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 (Scheme 498)
Scheme 498
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 (Scheme 499)
Scheme 499
ENGINE DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the causes of malfunctions not detected and remedied by routine maintenance.
These malfunctions may be classified as either mechanical (e.g., a strange noise), or performance (e.g., engine idles rough and stalls).
Refer to ENGINE DIAGNOSIS - PERFORMANCE or ENGINE DIAGNOSIS - MECHANICAL . Refer to FUEL SYSTEMS for fuel system diagnosis.
Additional tests and diagnostic procedures may be necessary for specific engine malfunctions that cannot be isolated with the Service Diagnosis charts. Information concerning additional tests and diagnosis is provided within the following
- Cylinder Compression Pressure Test. Refer to «CYLINDER COMPRESSION PRESSURE»(ref-189682-S39797369272005091100000) )
- Cylinder Combustion Pressure Leakage Test. Refer to «CYLINDER COMBUSTION PRESSURE LEAKAGE»(ref-189682-S16786042772005091100000) )
- Cylinder Head Gasket Failure Diagnosis. Refer to «CYLINDER HEAD GASKET FAILURE»(ref-189682-S28240726362005091100000) )
- Intake Manifold Leakage Diagnosis. Refer to «INTAKE MANIFOLD LEAKAGE»(ref-189682-S04496722662005091100000) )
- Lash Adjuster (Tappet) Noise Diagnosis. Refer to «HYDRAULIC TAPPETS»(ref-189682-S07491120442005091100000) )
- Engine Oil Leak Inspection. Refer to «ENGINE OIL LEAKS»(ref-189682-S34048211702005091100000) )
Scheme 500
Scheme 501
Scheme 502
Scheme 503
Scheme 504
Both the intake and exhaust valves are made of steel. The intake valve is 48.768 mm (1.92 inches) in diameter and the exhaust valve is 41.148 mm (1.62 inches) in diameter and has a 2.032 mm (0.080 inch) wafer welded to the tip for durability. These valves are not splayed.
The crankshaft see scheme 61 is of a cast nodular steel splayed type design, with five main bearing journals. The crankshaft is located at the bottom of the engine block and is held in place with five main bearing caps. The number 3 counterweight is the location for journal size identification.
Scheme 505
OPERATION
The crankshaft transfers force generated by combustion within the cylinder bores to the flywheel or flexplate.
Main bearings see scheme 64 are located in the cylinder block. One half of the main bearing is located in the crankshaft main bore the other half of the matching bearing is located in the main bearing cap. there are five main bearings. Number three main bearing is flanged, this flange controls crankshaft thrust.
Scheme 506
The main bearings encircle the crankshaft main bearing journals, this aligns the crankshaft to the centerline of the engine and allows the crankshaft to turn without wobbling or shaking therefore eliminating vibration. The main bearings are available in standard and undersize types.
The crankshaft front seal is a one piece viton seal with a steel housing. The front seal is located in the engine front cover.
The crankshaft seals prevent oil from leaking from around the crankshaft, either from the rear of the engine or from the engine front cover.
The crankshaft rear seal is a two piece viton seal. One part of the two piece rear seal is located in a slot in the cylinder block opposite the crankshaft main bearing cap, the second part of the two piece seal is located in the main bearing cap itself.
The crankshaft seals prevent oil from leaking from around the crankshaft, either from the rear of the engine or from the engine front cover.
The pistons are made of aluminum and have three ring grooves, the top two grooves are for the compression rings and the bottom groove is for the oil control ring. The connecting rods are forged steel and are coined prior to heat treat. The piston pins are press fit.
A gear-type positive displacement pump see scheme 90 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.
Scheme 507
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 bearing, 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 gallery 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 throw-off lubricates the camshaft lobes, distributor drive gear, cylinder walls, and piston pins.
The hydraulic valve tappets receive oil directly from the main oil gallery. The camshaft bearings receive oil from the main bearing galleries. The front camshaft bearing journal passes oil through the camshaft sprocket to the timing chain. Oil drains back to the oil pan under the No. 1 main bearing cap.
The oil supply for the rocker arms and bridged pivot assemblies is provided by the hydraulic valve tappets, which pass oil through hollow push rods to a hole in the corresponding rocker arm. Oil from the rocker arm lubricates the valve train components. The oil then passes down through the push rod guide holes and the oil drain-back passages in the cylinder head, past the valve tappet area, and then returns to the oil pan see scheme 91
Scheme 508
The aluminum intake manifold (Scheme 510) is a single plane design with equal length runners and uses a separate plenum, therefore the manifold does have a plenum gasket. It also uses separate flange gaskets and front and rear cross-over gaskets. Extreme care must be used when sealing the gaskets to ensure that excess sealant does not enter the intake runners causing a restriction. Whenever the intake manifold is removed inspect the plenum pan for evidence of excess oil buildup, this condition indicates that the plenum pan gasket is leaking.
Scheme 509
The intake manifold, meters and delivers air to the combustion chambers allowing the fuel delivered by the fuel injectors to ignite, thus producing power.
The exhaust manifolds see scheme 112 are constructed of cast iron and are LOG type with balanced flow. One exhaust manifold is attached to each cylinder head.
Scheme 510
The exhaust manifolds collect the engine exhaust exiting the combustion chambers, then channels the exhaust gases to the exhaust pipes attached to the manifolds.