Blocked filters/dodgy pump?

Hi. Got a Hoover 500M from my boss a few months ago.

Before I got it, it was sitting Idle for about 12 months - and it was used with a combination of irrigation water/rain water prior to that.

Anyway, just the other day, after doing 1 load no probs, once commencing the second load, during the fill cycle, water stopped coming into the machine (stopped pumping). Checked hoses etc for blockages - all ok.

All other cycles seem to work - but washed clothes by other means, and just used spin cycle.

Have tried since, but only a little amount of water trickles in, and stops.

Could a filter somewhere be the problem, or is the fill pump fudged and needs replacing?

Wouldn't mind knowing where the filters are also. Note the machine is used with cold water only.

Cheers for any help.

Dave