I have a 7 year old 773 G series which I bought as a non runner. I don't know much about it accept it has 5000 hrs. I think that it had been standing outside without being used for a good while. It has the following problems. Drives OK when on close to full trottle but if idling it creeps to the right quite quickly. Power is fairly OK on higher revs. Goes forwards and backwards fairly OK. I have changed all filters accept the case drain filters. Weather has been bad and where motors are is full of water. I removed the front covers where the pedals are and cleaned this out. It was full of dirt. Are there any other places to unblock to drain out this water? I have a service manual but it seems to be for an older version with just one bucket tipping ram. Any advice greatly appreciated.