I'm running a '92 Fiesta with a 1.1 HCS engine, and was a bit late (by ~1500 miles) adjusting the valve clearances when I got round to it yesterday.
I think the car was telling me I was late: in the last week or two it has seemed to pull even less well than usual - it won't hit 70mph as early as normal on well-known roads, and doesn't seem to want to accelerate from 60mph on even the tiniest inclines. Also, when checking the oil a week or two ago the level had dropped to just below min, when it had been above 3/4 the previous week. I topped it up and it's been fine since - and I haven't found oil spots anywhere. On the plus side, the awful top-end rattle stayed the same as ever...
I had the lid off yesterday, and the first thing I noticed while turning the crank was that the no. 4 inlet valve spring was only being compressed about half as much as the others. I checked its clearance, and could have stuck my little finger in the gap, never mind the feeler gauge. I tightened it up (it took at least a full turn on the adjuster) and turned the crank twice and re-checked it, and again it needed re-tightening, but seemed okay on the third check. None of the others needed anything like that kind of adjustment, but while doing it I split one of the adjuster bolts.
While checking that there weren't bits of bolt left in the rocker box I found a tiny spring (the gf tells me I can keep her tweezers in the toolbox now...) - about 1mm in diameter and 3cm long (though it'd obviously snapped), and it tapered to a point at one end (not the snapped end) - any idea what that is? Does it explain the one valve clearance that'd gone mental?
I bolted it all back together (leaving only 7.5 adjuster bolts in there) and took it out for a couple of roundabouts on the dual carriageway. It was as noisy as ever (I can usually fool myself it's a little quieter after I've done the tappets), and seemed as gutless as in recent weeks. I'm coming to accept that it isn't going to last much longer, but does anyone have an idea what's going on?
Oh, and if someone can check their crystal ball and tell me whether it's going to give out with a bang on the motorway, or fizzle out in a more convenient way, that'd be great....