Several forum members have found out (either the easy way or the hard way), the WP / WQ Fiesta 1.6L Duratec does not have an adjustable tensioner that can be used to fit the accessory drive belts. Instead, the belts are 'stretch fit,' meaning that they are designed to be stretched over the crankshaft and accessory drive pulleys, using special tools. Stretch fit belts are also designed to be 'single use only' and should be cut off, and not 'stretched-off,' then re-used (according to manufacturers).
Ford once sold the Fiesta stretch belts in a kit, with the special tools required to fit them. I recently spoke to Ford Spares and they confirmed that the kit is no longer available, only the belts themselves. Thankfully, there are some aftermarket alternatives, which I will give details of below.
Firstly, here is a diagram (courtesy of Gates) of the correct routing of the 1.6L accessory drive system:
As you can see, the crankshaft pulley is a double belt system,: a longer one that drives the water pump, alternator and A/C, and then a shorter belt that drives the power steering pump only.
The longer belt rides on the more 'inboard' section of crankshaft pulley, and the shorter power steering belt rides on the more outboard section.
The following video (proudly brought to your by Kincrome) shows the power steering belt being removed / fitted, using a 'universal' stretch fit belt tool, on the 1.6L Duratec:
http://www.youtube.com/watch?v=xlhOSXmOW4I
Here is the link on the Kincrome site:
https://www.kincrome.com.au/stretch-fit-belt-kit
An alternative tool to the Kincrome one is shown at the start of the video, which is the threaded/adjustable type, such as the following:
Gates make these, and sell them as SFT001 and SFT003 (pictured above). From what I can see, these are quite expensive, and you may want to consider the less expensive Laser tools versions, eg. Laser Tools 4999 and 4881 from eBay etc.
Fitting the longer accessory drive belt is a bit more of a mission, the easiest way being the Gates SFT002 kit or the Laser Tools 5919 kit (again, much cheaper). According the Laser, the 5919 is, "designed to be used where the universal tools will not work due to the double width crankshaft stopping the belt being fitted."
The kit contains a guide that fits over the water pump pulley, as well as a guide that fits over the crankshaft. Essentially the water pump pulley is rotated first, to help seat the belt over it, then the crankshaft pulley is rotated to finish the installation. Here is a video from Gates, showing the SFT002 being used:
http://www.youtube.com/watch?v=wRkzBqM4uPU
Full instructions are here from Gates:
http://www.gatesaustralia.com.au/~/m...0003.pdf?la=en
And better instructions (IMHO) from Laser:
http://www.lasertools.co.uk/items/PD...structions.pdf
The Gates belts part numbers are as follows:
5PK692SF (PS belt - shorter )
6PK1019SF (WP / Alt / A/C belt / - longer)
Bosch belts part numbers are:
5 EPK 690 1 987 946 141 (PS belt)
6 EPK 1019 1 987 946 142 (WP / Alt / A/C belt)
Set of two above: 1 987 946 197
As a matter of interest, the LS / LT Focus with 2.0L Duratec engine also has a stretch fit belt, driving the A/C only. The water pump / alternator is driven by a belt that also runs over an adjustable tensioner (thankfully). The power steering is electro-hydraulic.
