The first Zetec-branded engine was the
Zeta family, introduced for the 1992
model year powering the fifth generation of the European
Ford Escort, the third generation
Orion and the
Mk.3 Fiesta. The engine was originally available in 1.6 and 1.8 liter versions with a 2.0 liter version appearing in 1993 in the all-new
Mondeo. The "Zeta" name was dropped in favour of "Zetec" when Italian car maker
Lancia threatened to sue Ford for trademark infringement. The codename "Zeta" was originally used for the design of the cylinder head. A number of different systems were evaluated, and each one had a different codename using the Greek alphabet. The Zeta concept was the winner and the 4-valve-per-cylinder, DOHC design was used for the head of the replacement for the CVH in Europe and the US. The original manufacturing plan involved replacing the Dearborn manufactured CVH with Zeta. This resulted in the need to retain much of the architecture of the US CVH block. However, later in the development process, the plan was changed and the Chihuahua engine plant in Mexico was rebuilt to allow manufacture of the US engines. For Europe the decision was taken to build Zetas in Bridgend (Replacing CVH) and in Cologne. The US (2.0L) and European base engines were almost identical. However, crucially, the US management insisted that the US market engines had to have a
non-interference design, so that in the event of a timing belt failure the valves wouldn't collide with the pistons. As such the US market engines used different pistons and featured sinter forged
connecting rods (conventional cast rods were used in Europe). The non-interference design reduced
fuel economy by around 1–2%, which was considered too great a penalty for the European market. Early versions of the engine had a problem with sticking valves — far more evident in the UK (and in cold climates), where a driving style with earlier gear changes is more common than on the Continent — unless a special Ford formulation of oil was used. After small changes in 1995 to fix this problem the engine was known as the Zetec-E. This engine received a plastic inlet manifold and EGR derived from the
Mondeo. The Zetec had another redesign in 1998. This version, the Zetec-R, had a two-piece crankcase which helped damp out noise and vibration, conventional tappets with shims rather than hydraulic ones, and longer connecting rods with a lower piston compression height. This engine was used in turbocharged form in the
Focus RS and had (dubbed
Duratec RS). It was also used in the
Focus ST170 with a cylinder head modified by
Cosworth with Variable Valve Timing on the inlet cam and had . The Zetec can be identified by its silver cam cover with "DOHC 16v" on the bottom left. The Zetec-E has "ZETEC 16v" on the bottom left, and the Zetec-R has a black plastic cam cover. The Focus RS and ST170 (SVT) are both Zetec-R engines, despite being branded Duratec. Production of the Zeta family lasted from September 1991 through December 2004. Displacement ranged from 1.6 L to 2.0 L. It was replaced in most applications by the
Mazda MZR-based
Duratec 20, though some
Zetec-SE engines were used as replacements on the lower end. Ford Power Products sells the Zeta in 1.8 L and 2.0 L versions as the
MVH. The 2.0 L Zetec engine has seen some issues. Although the block and cylinder head are thermally stable, the coolant outlet housing for the thermostat is not. The housing used in the 2000–2004 model year US Ford Focus and 2001–2004 model year Ford Escape with 16-Valve DOHC engine is made from ABS plastic. It is bolted to the surface of the cylinder head on the right side of the engine with three bolts. The mating surface seals to the cylinder head with a rubber O-ring style gasket. The O-ring is held in place by a lip on the housing which is prone to cracking. The immediate inner portion of the housing will exhibit pitting and bubbling. Over time, pieces of the lip will break off, releasing plastic fragments into the cooling system. These fragments have not been known to cause any severe damage to the cooling system but the damaged lip on the housing will cause the O-ring seal to rupture. This allows coolant to leak out onto the upper transmission bell housing. The failure can result in severe loss of coolant. In 2010, a Focus SVT owner in Minnesota identified a fix for the housing issue. It involves the use of a more durable housing made for an earlier model of Zetecs. The lighter housing (still specified by Ford Parts) has not been corrected for the design flaw. It has a short service life and is the cause of repeated failures. As of September 2013, Ford sells both versions of the housing. The better version lists for $20 more (USA) and has barbed hose fittings, as opposed to the smooth fittings of the problematic fitting. Fixes have been identified for the housing used by the Focus SVT as well as for the simpler housing used by ordinary Foci. The 2.0 L version in the North American
Ford Contour/Mercury Mystique was a closely related replacement for the previous
CVH engine used in the
Ford Escort. ==Sigma==