8.0L V10 Engine: Overview Dodge Pickup R2500

DESCRIPTION

The 8.0 Liter (488 CID) ten-cylinder engine is a V-Type lightweight, single cam, overhead valve engine with hydraulic roller tappets. This engine is designed for unleaded fuel.

Engine lubrication system consists of a gerotor type oil pump mounted in the timing chain cover and driven by the crankshaft. The V-10 uses a full flow oil filter.

The cylinders are numbered from front to rear; 1, 3, 5, 7, 9 on the left bank and 2, 4, 6, 8, 10 on the right bank. The firing order is 1-10-9-4-3-6-5-8-7-2. (Scheme 1)

The engine serial number is located on the lower left front of the cylinder block in front of the engine mount. (Scheme 2) When component part replacement is necessary, use the engine type and serial number for reference.

Scheme 1

Scheme 2

DIAGNOSIS AND TESTING - 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).

See DIAGNOSIS AND TESTING-ENGINE DIAGNOSIS - PERFORMANCE or DIAGNOSIS AND TESTING-ENGINE DIAGNOSIS - MECHANICAL .

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

1. Cylinder Compression Pressure Test. See «DIAGNOSIS AND TESTING-CYLINDER COMPRESSION PRESSURE»(ref-174645-S18369439752005040700000) .
2. Cylinder Combustion Pressure Leakage Test. See «DIAGNOSIS AND TESTING - CYLINDER COMBUSTION PRESSURE LEAKAGE»(ref-174645-S03689628232005040700000) .
3. Cylinder Head Gasket Failure. See «CYLINDER HEAD»(ref-174645-S11019270062005040700000) .
4. Intake Manifold Leakage Diagnosis. See «INTAKE MANIFOLD»(ref-174645-S34232090772005040700000) .
5. Lash Adjuster (Tappet) Noise Diagnosis. See «HYDRAULIC LIFTERS»(ref-174645-S36621369472005040700000) .
6. Engine Oil Leak Inspection. See «LUBRICATION»(ref-174645-S15385582582005040700000) .

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

The alloy cast iron cylinder heads are held in place by 12 bolts. The spark plugs are located in the peak of the wedge between the valves. (Scheme 11)

Scheme 11

Die-cast magnesium cylinder head covers reduce noise and provide a good sealing surface. A steel backed silicon gasket is used with the cylinder head cover. This gasket can be used again. (Scheme 12)

Scheme 12

The valves are arranged in-line and inclined 18°. (Scheme 13) The rocker pivot support and the valve guides are cast integral with the heads.

Scheme 13

The pistons are elliptically turned so that the diameter at the pin boss is less than its diameter across the thrust face. (Scheme 14) This allows for expansion under normal operating conditions. Under operating temperatures, expansion forces the pin bosses away from each other, causing the piston to assume a more nearly round shape.

Scheme 14

All pistons are machined to the same weight, regardless of size, to maintain piston balance.

The piston pin rotates in the piston only and is retained by the press interference fit of the piston pin in the connecting rod.

The pistons have a unique dry-film lubricant coating baked onto the skirts to reduce friction. The lubricant is particularly effective during engine break-in, but with time, the material becomes embedded into cylinder bore walls and continues to reduce friction.

The pistons are LH and RH bank specific.

A pressure feed type (gerotor) oil pump is located in the engine front cover. The pump uses a pick-up tube and screen assembly to gather engine oil from the oil pan. (Scheme 15)

Scheme 15

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 inner and outer gears of the oil pump, then forced through the outlet in the engine front cover. An oil gallery in the front cover 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 tappet galleries, which extends the entire length of block.

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, 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. (Scheme 16)

Scheme 16

The aluminum intake manifold has two plenum chambers an upper and lower which supply air to five runners each. Passages across the longitudinal center of the manifold feed air from the throttle body to the plenum chambers. (Scheme 17)

Scheme 17

Engine exhaust manifolds are made of high molybdenum ductile cast iron. A special ribbed design helps control permanent dimensional changes during heat cycles. (Scheme 18)

Scheme 18

The exhaust manifolds collect the engine exhaust exiting the combustion chambers, then channels the exhaust gases to the exhaust pipes attached to the manifolds.

Scheme 19

1. Disconnect the negative cable from the battery.
2. Raise and support the vehicle.
3. Remove the bolts and nuts attaching the exhaust pipe to the engine exhaust manifold.
4. Lower the vehicle.
5. Remove the exhaust heat shields. (Scheme 19)
6. Remove the dipstick bracket from the exhaust manifold (right side only).
7. Remove bolts attaching manifold to cylinder head.
8. Remove manifold from the cylinder head. Discard the gasket.