I used my mower again recently and after forcing it to start, it run but sluggishly. Whilst using it, I noticed the carburettor together with the petrol tank was slightly moving. To my amazement, I found the carburettor mounting screw was missing. Not one but both. I can't believe that both are missing and nowhere to be found. I can understand one can be missing but both is out of ordinary. This could explain why the choke is not working as it should be.