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Engine - 4.0L (SOHC): Specifications Ford Explorer IV

Mechanical 1 illustration ~514 words

GENERAL SPECIFICATIONS

ItemSpecification
Engine
Displacement4.0L (244 CID)
Number of cylinders6
Bore100.4 mm (3.953 in)
Stroke84.4 mm (3.32 in)
Firing order1-4-2-5-3-6
Oil pressure minimum at 2,000 rpm (engine at normal operating temperature)103 kPa (15 psi)
Engine weight (without accessory drive components or flexplate)189 kg (417 lb)
Cylinder Head and Valve Train
Cylinder head gasket surface flatness0.08 mm (0.003 in) total
Combustion chamber volume65.197 ± 2.068-2.018 cc
Valve arrangement (front to rear) - LHI-E-I-E-I-E
Valve arrangement (front to rear) - RHE-I-E-I-E-I
Valve guide bore diameter7.00-7.018 mm (0.276 in)
Valve stem diameter - intake6.965-6.98 mm (0.274-0.275 in)
Valve stem diameter - exhaust6.95-6.965 mm (0.27-0.274 in)
Valve stem-to-guide clearance - intake0.020-0.053 mm (0.001-0.002 in)
Valve stem-to-guide clearance - exhaust0.035-0.068 mm (0.001-0.003 in)
Valve head diameter - intake45.9-46.1 mm (1.807-1.815 in)
Valve head diameter - exhaust38.9-39.1 mm (1.531-1.539 in)
Valve face runout0.03 mm (0.001 in)
Valve face angle45 degrees
Valve seat width - intake1.273-2.121 mm (0.05-0.083 in)
Valve seat width - exhaust1.556-2.404 mm (0.061-0.095 in)
Valve seat runout0.059 mm (0.002 in)
Valve seat angle45 degrees
Valve spring free length43.1 mm (1.7 in)
Valve spring squareness± 1.5 degrees
Valve spring compression pressure @ specified height (lbs)275-305 N @ 35.9-36.7 mm (202.84-224.968 lb @ 1.413-1.445 in)
Valve spring installed height39.86-40.86 mm (1.569-1.609 in)
Valve spring installed pressure320 N (72 lb)
Roller follower ratio1.98:1
Camshaft
Theoretical valve lift @ 0 lash11.93 mm (0.472 in)
Lobe lift6.584 mm (0.259 in)
Allowable lobe lift loss0.127 mm (0.005 in)
Journal diameter27.935-27.96 mm (1.099-1.101 in)
Camshaft journal bore inside diameter28.0-28.03 mm (1.102-1.104 in)
Camshaft journal-to-bearing clearance0.04-0.095 mm (0.002-0.004 in)
Runout0.05 mm (0.002 in)
End play0.075-0.185 mm (0.003-0.007 in)
Cylinder Block
Cylinder bore diameter100.4 mm (3.953 in)
Cylinder bore maximum taper0.025 mm (0.001 in)
Cylinder bore maximum out-of-round0.025 mm (0.001 in)
Main bearing bore inside diameter60.620-60.634 mm (2.387-2.387 in)
Head gasket surface flatness0.1 mm (0.004 in) overall
Crankshaft
Main bearing journal diameter56.980-57.0 mm (2.243-2.244 in)
Main bearing journal maximum taper0.008 mm (0.0003 in)
Main bearing journal maximum out-of-round0.008 mm (0.0003 in)
Main bearing journal-to-cylinder block clearance0.008-0.062 mm (0.0003-0.0024 in)
Connecting rod journal diameter53.98-54.0 mm (2.125-2.126 in)
Connecting rod journal maximum taper0.008 mm (0.0003 in)
Connecting rod journal maximum out-of-round0.008 mm (0.0003 in)
Crankshaft maximum end play0.05-0.32 mm (0.002-0.0126 in)
Main Bearings
Clearance to crankshaft0.021-0.039 mm (0.0008-0.0015 in)
Clearance to crankshaft allowable0.013-0.048 mm (0.0005-0.002 in)
Bearing wall thickness1.8-1.806 mm (0.0709-0.0711 in)
Piston and Connecting Rod
Piston diameter - coded standard100.380-100.400 mm (3.952-3.9528 in)
Piston diameter - coded 0.5100.880-100.900 mm (3.971-3.972 in)
Piston diameter - coded 1.0101.390-101.400 mm (3.991-3.992 in)
Piston-to-cylinder bore clearance0.030-0.050 mm (0.0012-0.002 in)
Piston ring end gap - top0.200-0.450 mm (0.008-0.018 in)
Piston ring end gap - bottom0.40-0.60 mm (0.016-0.024 in)
Piston ring groove width - top1.23-1.25 mm (0.0484-0.0492 in)
Piston ring groove width - bottom1.52-1.54 mm (0.0598-0.0606 in)
Piston ring groove width - oil ring3.01-3.03 mm (0.1185-0.1193 in)
Piston ring width - top1.175-1.190 mm (0.0463-0.0469 in)
Piston ring width - bottom1.475-1.490 mm (0.0581-0.0587 in)
Piston ring-to-groove clearance - top0.040-0.075 mm (0.0016-0.0030 in)
Piston ring-to-groove clearance - bottom0.030-0.065 mm (0.0012-0.0026 in)
Piston pin bore diameter23.958-23.976 mm (0.943-0.944 in)
Piston pin diameter (red)23.994-23.997 mm (0.9446-0.9448 in)
Piston pin diameter (blue)23.997-24.000 mm (0.9448-0.9449 in)
Piston pin length72.0-72.8 mm (2.835-2.866 in)
Piston pin-to-piston fit0.01-0.016 mm (0.0004-0.0006 in)
Piston pin-to-connecting rod clearance0.01-0.016 mm (0.0004-0.0006 in)
Connecting rod pin bore diameter23.958-23.976 mm (0.943-0.944 in)
Connecting rod length (center-to-center)145.965-146.035 mm (5.747-5.749 in)
Connecting rod maximum allowed bend0.013 mm (0.0005 in) per 25.4 mm (1.000 in)
Connecting rod maximum allowed twist0.038 mm (0.0015 in) per 25.4 mm (1.000 in)
Connecting rod bearing bore diameter56.82 mm-56.84 mm (2.237 in-2.238 in)
Connecting rod bearing-to-crankshaft clearance0.022-0.064 mm (0.0008-0.0025 in)
Connecting rod side clearance0.092-0.268 mm (0.0036-0.0106 in)

GENERAL SPECIFICATIONS

TORQUE SPECIFICATIONS

DescriptionNm
A/C line fitting nuts15
A/C tube bracket nut10
Accessory drive bracket bolts42
Accessory drive belt tensioner bolt47
Balance shaft bolts29
Balance shaft chain guide bolts10
Balance shaft chain tensioner bolts29
Battery cable retainer bracket-to-frame nut15
Battery cable-to-engine front cover bracket nut20
Battery cable-to-power distribution box nut12
Camshaft bearing cap bolts a
Camshaft sprocket bolt85
Camshaft sprocket bolt (w/SST)61
Cassette-to-cylinder block bolt19
Cassette-to-cylinder head bolt, RH10
Cassette-to-cylinder head bolt, LH12
Connecting rod bolts a
Coolant expansion tank bolts7
Coolant pump bolts10
Coolant pump pulley bolts25
Crankshaft pulley bolt a
Crossmember bolts103
Cylinder block cradle bolts (inside) a
Cylinder block cradle bolts (outside)14
Cylinder block cradle nuts (outside)10
Cylinder block cradle inserts3
Cylinder block cradle Torx bolts8
Cylinder head bolts a
Electrical harness-to-rear of engine bolts47
Engine front cover bolts19
Engine lifting eye bolts (service)37
Engine support insulator bracket bolts80
Engine support insulator nuts90
Engine support insulator through bolt103
Exhaust manifold nuts22
Exhaust manifold studs12
Exhaust manifold-to-converter nuts40
Exhaust manifold-to-EGR system module tube fittings34
Flexplate bolts a
Front axle housing bolts66
Front stabilizer bar bracket bolts55
Fuel rail bolts24
Fuel supply tube bracket-to-valve cover bolt6
Fuel supply tube-to-fuel rail bolts6
Generator bracket bolts42
Generator wire nut9
Ground strap-to-RH cylinder head bolt10
Ground wire nut9
Heater hose tube bracket front bolt34
Heater hose tube bracket rear bolt23
Hood hinge bolts12
Hydraulic camshaft tensioner44
Ignition coil bracket bolts10
Intake manifold bolts11
Jackshaft chain guide bolts19
Jackshaft chain tensioner bolts9
Jackshaft front sprocket bolt a
Jackshaft rear sprocket bolt a
Jackshaft thrust plate bolt11
Knock sensor (KS) bolt20
Main bearing cap bolts97
Oil cooler hose bracket bolt25
Oil cooler insert57
Oil filter13
Oil filter adapter bolt57
Oil filter adapter insert33
Oil level indicator tube bracket bolt10
Oil pan bolts11
Oil pan drain plug26
Oil pressure switch13
Oil pump bolts19
Oil pump drive bolt19
Oil pump screen cover and tube bolts10
Power steering fluid reservoir bolt7
Power steering fluid reservoir-to-power steering pump hose bracket bolt11
Power steering pressure hose bracket bolt11
Power steering pump bolts25
Power steering pump pulley bolts25
Radiator fan shroud bolts7
Spark plugs20
Stabilizer bar bracket bolts70
Starter B terminal nut12
Starter S terminal nut6
Thermostat housing bolts11
Transmission cooler tube bracket nut23
Transmission-to-cylinder block cradle bolts47
Valve cover bolts10
Wiring harness-to-front cover bracket nut20
Wiring harness-to-RH cylinder head bracket bolt47
Wiring harness-to-throttle body bracket nut9

TORQUE SPECIFICATIONS

a Refer to the appropriate procedures.

The 4.0L SOHC engine consists of the following

  1. Single overhead camshafts
  2. Sequential multi-port fuel injection (SFI)
  3. Distributorless ignition system
  4. Aluminum cylinder heads
  5. Cast-iron, 60-degree V cylinder block
  6. Jackshaft
  7. Unique engine timing configuration

The 4.0L engine is a 2-valve-per-cylinder, overhead camshaft engine. The engine features a jackshaft located in the cylinder block above the crankshaft and driven by the crankshaft via a sprocket and chain assembly. The jackshaft drives the 2 camshafts via 2 timing chain cassettes, the LH located on the front of the engine and the RH located on the rear of the engine. The oil pump is driven by the crankshaft via a sprocket and chain. The piston assembly is an aluminum piston with a powdered metal connecting rod. The engine uses a distributorless ignition system.

Identification - Always refer to these labels when installation of new parts is necessary, or when checking engine calibrations. The engine parts often differ within a cubic inch displacement (CID) family. Verification of the identification codes will make sure that the correct parts are obtained. These codes contain all the pertinent information relating to the dates, optional equipment and revisions. The Ford Master Parts Catalog contains a complete listing of the codes and their application

Code Information - The engine code information label, located on the side of the valve cover and the front side of the valve cover, contains the

  1. engine build date.
  2. engine plant code.
  3. engine code.

Exhaust Emission Control System - Operation and necessary maintenance of the exhaust emission control devices used on this engine are covered in the Introduction - Gasoline Engines .

Induction System - The sequential multi-port fuel injection (SFI) provides the fuel/air mixture needed for combustion in the cylinders. The 6 solenoid-operated fuel injectors

  1. are mounted in the cylinder heads.
  2. meter fuel to the air intake stream in accordance with engine demand.
  3. are positioned so their tips direct fuel just ahead of the engine intake valves.

PCV System - All engines are equipped with a closed-type PCV system recycling the crankcase vapors to the intake manifold.

Lubrication System - The engine lubrication system operates as follows

  1. Oil is drawn into the oil pump through the oil pump screen cover and tube in the sump of the oil pan.
  2. Oil is pumped through the oil filter on the right front side of the cylinder block.
  3. Oil enters the main gallery where it is distributed to the crankshaft main journals and to the cylinder head.
  4. From the main journals, the oil is routed through cross-drilled passages in the crankshaft to lubricate the connecting rod bearings. Controlled leakage through the crankshaft main bearings and connecting rod bearings is slung radially outward to cool and lubricate the cylinder walls as well as the entire connecting rod, piston and piston ring assembly.

Scheme 1

Scheme 1

For basic engine mechanical concerns, refer to ENGINE SYSTEM - GENERAL INFORMATION . For driveability concerns, refer to the Introduction - Gasoline Engines .