I am getting a bit bored of things not coming completely clean...

[Hopefully]

I have used a variety of eco washing liquids, but I think the problem is basically that our machine is incredibly old (rented, and moving next year, not worth buying our own in case the next place has a newer machine). All our whites come out slightly yellowy, and stains just don't come out at all.

Any eco tips for (a) stain removal (mostly on whites, the odd coloured thing) and (b) whitening whites in general?

Always pre- treat stains first. Would need to google but lemon juice comes to mind. Line drying in the sun has a good bleaching effect.

Spoonful of bicarb of soda in with the wash helps. Treat stains on whites with bicarb of soda mixed to paste with lemon juice. Not 100% green but better than bleach at least!
Can't believe I'm posting laundry tips at this time of night.

Thanks for the late night laundry tips! Will try them, as I'm beginning to look like a complete bag lady...