How often are you draining the filter head of water ?, this will make it harder to start, as will a dodgy too small a battery.
I know when I had a mk4 escort 1.8D, the battery that was recommended by one battery maker was seriously tiny, and same as a 950 fiesta one, fine in summer, wouldn't even nudge the engine in the winter!!, fitted a mega whoppa battery of 980CCA instead of 330CCA, it spun over then!!
tabetha