If you can afford to buy a battery you can afford a multimeter - £9.29 in Screwfix http://www.screwfix.com/p/lap-mas830b-digital-multimeter-600v/75337?kpid=75337&cm_mmc=Google-_-Product%2520Listing%2520Ads-_-Sales%2520Tracking-_-sales%2520tracking%2520url&gclid=Cj0KEQjw-ezKBRCGwqyK0rHzmvkBEiQAu-_-LCLR2hydt-9LDmzNo3_UXpkMV2Bg4K7rrdnZjvbdiRYaApJt8P8HAQ&gclsrc=aw.ds&dclid=COz_tZGg79QCFVK6GwodLL8JAg Electricity isn't that tough - and when combined with YouTube, fault finding a starting problem using a multimeter is child's play. This nine quid will tell you if I'm correct about the battery, before you buy a battery. As my wife, my kids, and everybody who's ever met me will tell you, I'm frequently wrong.