Help! I have a tiler 1970-1972 25hp Johnson. I bought it from a guy that had it sitting for about 5yrs along with a 18hp Evinrude(roughly around the same year as the 25hp). I got it 25hp running, but it would only run for about 30sec and die. I took the carb off and completely re-built, soaked it in carb cleaner, and changed the spark plugs. It seemed to be okay until, I got it on the water. It had a rough idle and about half way to full throttle, it would lose a lot of power and hesitate until I got it up to full throttle and then it seemed to run great. I decided to clean the carb again, change the gas lines, and put on a in line fuel filter. Getting back on the water, it still had a rough idle, but ran perfect in gear 1/5 throttle and up. About 5 miles later, it then would go from full throttle running perfect to almost a complete power loss. I went to running about 30mph to about 8mph, back and forth until it was nothing, but 8mph, like the spark plugs had fouled out. I checked the compression and both cylinders are little above 120. Considering the carb on the 18hp was identical to the 25hp, I rebuilt it, soaked it in carb cleaner, changed the spark pluges again, and the gas(50:1 w/87 unleaded fuel) and put it on the 25hp, but still the same thing. In addition, the bottom spark plug seems to be getting oil on it and now I have not had it running right since that one day. When it's idling, it seems like it's missing, it goes from rough idle to, ever so often, jumping, acting like it wants to run right, but does not. I now don't know what else to do, but think, I made a terrible purchace. PLEASE HELP!!!!!
