Engine

Engine

The 4.0L SOHC engine consists of the following:

- Single overhead camshafts
- Sequential Multi-Port Fuel Injection (SFI)
- Distributorless ignition system
- Aluminum cylinder heads
- Cast-iron, 60-degree V cylinder block
- Jackshaft
- 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.


Engine 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 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 Catalog Advantage(TM) or equivalent contains a complete listing of the codes and their applications.


Engine Code Information Label

The engine code information label is located on the side of the LH valve cover. It contains the following:

Without Oil Cooler










With Oil Cooler










Engine Cylinder Identification






Exhaust Emission Control System

Operation and required maintenance of the exhaust emission control devices used on this engine is covered in Computers and Control Systems Information.


Induction System

The SFI provides the fuel/air mixture needed for combustion in the cylinders. The 6 solenoid-operated fuel injectors:

- are mounted in the cylinder heads.
- meter fuel to the air intake stream in accordance with engine demand.
- 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:

- Oil is drawn into the oil pump through the oil pump screen cover and tube in the sump of the oil pan.
- Oil is pumped through the oil filter on the right front side of the cylinder block.
- Oil enters the main gallery where it is distributed to the crankshaft main journals and to the cylinder head.
- 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.