First off, let it be known that I don't know Jack about outboard motors. I bought my first boat yesterday. It came with a 1971 Mercury 9.8 hp and a 1976 Mercury 7.5 hp. Both motors have been maintained well. The man I bought it from has had health problems lately and has given up fishing. He handed me the owners manuals for both motors when I picked the boat up and they look brand new. Anyways, the 9.8 hp motor has been sitting up for a year and a half or better and the 7.5 hasn't been run in 8 months. The seller said he came out and pulled the starter cord every month to keep the engines from seizing up but neither one of them were started during that time. I launched this morning with the 9.8 on and it ran pretty bad from the get-go. It wouldn't get up to speed and would only run smoothly while at idle speed. I put the 7.5 motor on and it ran pretty rough and also had problems getting up to speed. After I ran the 7.5 awhile it started running alot better. I've been told I have varnish in the carb and it needs to be cleaned and the plugs and some other part need to be replaced. If anyone could give me some solid advice on how I should proceed I sure would appreciate it.