Thanks JD. We have checked fan belt and tightened. We have had lorry about 10 years and seem to keep getting this problem (have had recon alternator twice already and 1 starter motor). We also seem to change all the batteries about every two years. Lorry is used weekly through the summer but only about once a month from Oct to April. Has two batteries to start and 1 to run the lights inside "caravan" section (this is horse box), never use radio or tacho.
hogarth 1953, October 2008