Rode ski yesterday, ran great. Checked the spark plugs (we just rebuilt carbs) and they appeared to be a little rich, but no problems. This morning, i went to run a compression check on my engine, opened the hood, and the engine was covered with dew, and then i took the spark plugs out, and they appeared to be oil fouled. Checked tank and it was at normal level. Suggestions? Could it be that i just need to let my good synthetic stuff run longer?