Zetec-E Engine Design (Focus 1)

Basic concept

The Zetec-E engine is a four-cylinder, in-line, 16-valve DOHC engine. The 16-valve cylinder head provides better filling quality, especially at high crankshaft speeds.

The cylinder head is made of aluminum alloy, while the cylinder block is made of cast iron.

Center Timing Belt Cover/Front Engine Mount Bracket

The new timing belt cover is additionally reinforced with a vertical support. This means that in order to install the new timing belt, the central timing belt cover and therefore the front engine support must be removed.

Cylinder head

Combustion chamber

The spark plug, located in the center of the roof-shaped combustion chamber, ignites the air-fuel mixture in the combustion chamber. The central location of the spark plug ensures uniform distribution of the flame front throughout the combustion chamber, thereby simultaneously reducing the engine's tendency to detonate.

Valve mechanism

The two camshafts are driven by a single drive belt, and each shaft acts on two valves in each cylinder via adjustable tappets. Due to the flow of exhaust gases through the exhaust valves, these valves are exposed to very high temperatures. The exhaust valves have a special coating that allows them to dissipate heat better. Each valve is closed by its own valve spring. In order to adjust the valve clearances, it is necessary to replace the adjusting shims in the valve tappets. There are 52 different shim thicknesses. The thickness of the adjusting shim is stamped on its back in the form of a number corresponding to the thickness of the shim to the nearest hundredth of a millimetre (for example: the number 222 = 2.22 mm). Due to the limited space in the cylinder head, the camshaft must be removed to replace the adjusting shims. Absolute precision is required when performing the adjustment procedure to avoid having to remove and install the camshaft more than once. The camshaft cams are offset from the valve tappet centers. As a result, at an engine crankshaft speed of approximately 3,000 rpm, the valve tappets begin to rotate, and this rotation is transmitted to the valves. Rotation of the valves is desirable because it leads to uniform seating of the valves in their seats and prevents running-in of the valves in one position and leaks in the valves.

Pos.	Spare Part No	Name
1	-	Camshaft Bearing Cap Bolt
2	-	Camshaft Bearing Cap
3	-	Intake camshaft
4	-	Exhaust camshaft
5	-	Oil gallery plug
6	-	Valve clearance adjustment shim (shim)
7	-	Valve lifter
8	-	Rusk
9	-	Valve spring plate
10	-	Valve spring
11	-	Valve stem oil seal
12	-	Exhaust valves
13	-	Intake valves
14	-	Cylinder head
15	-	Cylinder head bolt
16	-	Spark plug
17	-	Engine Lifting Eye Bolt
18	-	Engine lifting eye
19	-	Camshaft Pulley Bolt
20	-	Camshaft pulleys
21	-	Oil seals for camshafts
22	-	Guide bush for front camshaft bearing cap
23	-	Front camshaft bearing cap

Mechanical pusher

Pos.	Spare Part No	Name
1	-	Adjusting shim (installed on the top of the pushrod)
2	-	Mechanical pusher

• In the new generation Zetec-E engines, the hydraulic tappets can also be replaced with mechanical ones. This is achieved by using high-quality materials and optimizing the cam profile.
• The degree of valve wear is so low that there is no need to check and adjust the valve clearances until 150,000 km (90,000 miles) have been covered.

Timing belt drive (with lower intermediate pulley)

Pos.	Spare Part No	Name
1	-	Intake camshaft with pulley
2	-	Exhaust camshaft with pulley
3	-	Intermediate pulley
4	-	Coolant pump outer housing on cylinder block
5	-	Intermediate pulley
6	-	Crankshaft pulley
7	-	Modified timing belt guide
8	-	New spring-loaded timing belt tensioner with eccentric adjustment for timing belt removal and installation

Timing Belt Drive (without Lower Intermediate Pulley)

Pos.	Spare Part No	Name
1	-	Intake camshaft with pulley
2	-	Exhaust camshaft with pulley
3	-	Intermediate pulley
4	-	Coolant pump outer housing on cylinder block
5	-	Crankshaft pulley
6	-	Modified timing belt guide
7	-	New spring-loaded timing belt tensioner with eccentric adjustment for timing belt removal and installation

• The installation of the lower intermediate pulley was discontinued in January 1999.
• The timing belt should always be replaced after 150,000 km (90,000 miles) or 10 years.
• The timing belt should always be replaced if it has been removed during repair work.

Timing belt tensioner

CAUTION: The timing belt should only be tightened when the timing belt is moved in a counterclockwise direction.

The correct tension of the timing belt is ensured by an automatic belt tensioner. When a new belt is installed, the tensioner moves to the basic position (arrow (3) and mark (2) in line). This basic setting is ensured by one of the cams (4). The other (spring-loaded) cam ensures that the correct belt tension is maintained when the engine is running. The belt tensioner moves up to 30 degrees from the center in both directions.

NOTE: Do not re-tension the belt as there is a risk of exceeding the allowable rotation angle in one direction. The basic belt tensioner setting is only applicable to a new timing belt. Re-tensioning the belt may cause belt wear or belt wobble.

It is no longer possible to check the basic setting after removing the adjustment tools and pins (the force from the valve springs is transmitted to the belt and changes the position of the belt tensioner).

Automatic timing belt tensioner

Pos.	Spare Part No	Name
1	-	Bracket fixed to sheet metal cover
2	-	Mark
3	-	Arrow
4	-	Basic adjustment cam

Elements installed on the cylinder head

Intake manifold

The new Zetec-E engines are equipped with an intake manifold made of fiberglass reinforced plastic. The intake manifold channels are arranged in such a way that they have the same length for each cylinder.

This provides the following benefits:

• Less heat transfer to the nozzles, thus preventing the occurrence of a "steam lock";
• Lighter construction;
• Less fuel condensation on the walls of the intake manifold after a cold start;
• Less heating of the intake air when the engine is warm.

Elements installed on the intake manifold

Pos.	Spare Part No	Name
1	-	Injector plug connector
2	-	Fuel line clamp bolt
3	-	Fuel manifold
4	-	Nozzle
5	-	Nozzle holder
6	-	Intake Manifold Gasket
7	-	Intake manifold
8	-	Quick release coupling for brake booster vacuum hose
9	-	Crankshaft speed control valve gasket in idle mode (by ISC valve)
10	-	ISC valve
11	-	Throttle body gasket
12	-	Fuel manifold bolt
13	-	Throttle body
14	-	Fuel Line Bracket Bolt
15	-	Throttle body bolt
16	-	Fuel line bracket
17	-	Fuel line clamp

Cylinder block

Crankshaft

The crankshaft is supported by five bearings and has a counterweight for each cylinder. The central main bearing has two thrust half rings that guide the crankshaft in the axial direction and determine its axial clearance.

Crankshaft bearings

Pos.	Spare Part No	Name
1	-	Cylinder block main bearing shell
2	-	Main bearing shell with thrust half-rings
3	-	Crankshaft
4	-	Segment key for crankshaft pulley hub
5	-	Bearing insert, main bearing cap
6	-	Main bearing cap
7	-	Main bearing cap bolt

Connecting rod bearings

The connecting rod bearings are numbered from 1 to 4, starting from the side where the timing belt is located. It is almost impossible to confuse the connecting rod bearing caps and the connecting rods, since during manufacturing the connecting rod bearing caps are simply cut off from the connecting rods. Therefore, the mating surface profile of each connecting rod bearing cap corresponds to only one of the connecting rods.

Engine crankcase reinforcement block

Lower crankcase

The engine crankcase reinforcement block is designed to dampen engine vibrations. This leads to a further reduction in the noise level in the vehicle interior. Starting from 01.99, the seal between the lower engine crankcase and the cylinder block is a gasket with a metal carrier plate (vehicles before 01.99 have a rubber gasket).

Remote elements of the engine crankcase reinforcement block

NOTE: From 01.99 only round spacers are used.

The spacers of the engine crankcase reinforcement block are used to compensate for increased clearances between the gearbox and the engine crankcase reinforcement block. For additional information, refer to the chapter Engine Assembly in this section.

Oil pan

The engine is closed from below by an oil sump, stamped from a metal sheet, which (the sump) is attached directly to the engine sump reinforcement block. A 3 mm wide bead of sealant is used to ensure the tightness of the joint.

Engine management

Powertrain Control Module (PCM)

The Zetec-E engine is controlled by a PCM. To be able to do this, the PCM requires a large amount of information about the current operating condition of the engine. The PCM receives this information from numerous sensors.



RSM manages:

• fully electronic ignition system (EI),
• sequential Electronic Fuel Injection (SEFI),
• air conditioning system in combination with a cooling system.

The text is available on the specified website info portal fordbook.ru