There are a few subtle differences between the parts used on the Escort spec Zetec and the Mondeo spec Zetec. This can provide some options to overcome potential obstacles to your application.
The difference between the Escort and the Mondeo oil pumps is the filter mount. The Escort unit is slightly more compact and mounts the filter at a different angle. In the Escort mk3/4 application there is not enough clearance for the oil filter when using the Mondeo pump so the Escort pump has to be fitted.
There are two differences between the two water pumps. The first obvious difference is the angle of the output hose connection. For Escort mk3/4 applications the Escort sourced pump is required as the Mondeo version will foul the alternator and cause plumbing issues due to the tight bend that would be required to connect to the radiator.
The other difference is the direction of rotation of the two pumps. If you look closely at the two grainy photos you will see that the pump vanes are angled opposite to each other. The reason for the different directions of rotation is because the accessories drive belt is routed differently on the two cars. On the Escort the water pump is driven conventionally and so it uses a normal grooved pulley. The Mondeo pump is driven by the back of the belt and so it uses a smooth pulley.
So make sure you use the correct pulley and route the belt accordingly!
The sumps are different between the two donor vehicles that may give clearance options for cross members and steering racks in rear wheel drive applications or exhaust routing in front wheel drive applications. You will also need the corresponding oil pick-op pipe for the oil pump and the correct dipstick complete with outer tube. For Escort Mk3/4 applications the Escort spec sump is required to provide clearance for the exhaust.
The Mondeo mounts the alternator high up on the inlet side if the engine. I cannot remember how or where the alternator is mounted on the Escort sourced engines.
For mk3/4 Escort applications the alternator is mounted in the same position that it was in on the original engine, low down on the exhaust side. An original CVH alternator bracket can be bolted in place onto the block but these brackets came in a variety of styles. If you are lucky you will find one with provision for mounting the slotted mounting arm that facilitates tensioning of the belt. on the CVH there was a bolt hole in the block that the original tensioning arm was bolted to but this is not present on the Zetec so you may have to fabricate a bracket.
There are a number of options for the inlet manifold from the Mondeo, Escort or even the mk1 Focus. The early Zetec powered Escorts used a cast alloy inlet manifold with a forward facing throttle body with an intake pipe routed straight over the top of the engine. This arrangement will work in mk3/4 Escort applications but there is a better option. The Mondeo inlet manifold is a plastic affair that sits down the back of the engine block with a vertically facing throttle body. This manifold is too bulky for use in mk3/4 Escort applications as it fouls on the brake pedal cross-bar. The mk1 Focus manifold is also made from plastic and is very similar to the Mondeo item but it is slimmer in overall size (not in port diameter) and so fits in mk3/4 Escort applications and is what I used. It also comes in 2.0ltr guise so can be had with the correct size throttle body and injectors.
This is probably more applicable to front wheel drive / transverse applications than rear wheel drive applications. The two stock exhaust manifolds angle and route the exhaust systems differently, hence the different sump designs. Whichever you use, be sure to use the corresponding crankcase breather system oil separator as they are different shapes and will foul on the manifold/downpipe if the wrong one us used. For Escort mk3/4 applications the Escort manifold and downpipe are required.
The choice of flywheel and clutch will of course depend on what gearbox you are using. The Zetec requires a 36 tooth trigger wheel to provide crank position data. As standard this is incorporated into the engine facing side of the flywheel so ideally a flywheel with the same arrangement is required. you may well be able to use the Zetecs original flywheel, you will have to research this for yourself. Be aware that the Escort flywheel is slimmer than the Mondeo version and so the clutch will sit a bit closer to the engine. For the mk3/4 Escort application using the cars original BC gearbox the ideal flywheel is that from the rare CVH EFI Escort.
Back of the block with the CVH engine to gearbox bell housing sandwich plate fitted. The crank position sensor is clearly visible to the left of the crankshaft output flange.
CVH EFI flywheel fits but will need the mounting bolt holes enlarging by 0.5mm.
Uprated organic CVH Escort RS Turbo clutch kit.
Note the toothed wheel cast into the back of the flywheel. This opening needs to be sealed.
Original CVH engine to gearbox bell housing sandwich plate with extra section welded in place to close the opening.
The join of the extra metal can be seen clearer here.
On the mk3/4 Escort BC gearbox the lower debris guard also needs modifying.
The crank seal housing is a slightly larger diameter to the curved flange needs cutting away to suite.
The contents of this website are purely a reflection of my own experiences and knowledge gained whilst working on my various projects. Anything you do based on what you have read here is done so entirely at your own risk. Personally I wouldn't trust someone like me with a lawn mower! You have been warned! Flapper-bat!