Yeah that was one of my main suspicions so I put a jump lead from the negative terminal on the battery to the inlet manifold but had no change, turned out to be a bad connection on the live from the battery
Thankyou very much Chris much appreciated, after trying out a few of the potential scenarios and measuring the voltage across battery terminals (12.6v) and various places I saw a huge drop from battery positive to live on starter motor so I put a jump lead from the positive terminal on the battery to the main power in on the starter motor then turned the key and it started fine, then knowing that it was to do with the main wire going from the battery to the starter motor I thought first thing was to disconnect the clamp off the positive terminal on the battery and give the terminal a good cleanup with a low grade sandpaper and then fired up perfect and working fine now was confused because I thought as the starter motor was giving a click that there must of been power there but I guess it was receiving less power due to a bad connection. Thanks again for your help