I've got a 1988 Mariner 100 hp. I can take the boat out for about 20-30 minutes and runs fine, after that the boat starts losing speed it's not stalling just slowing down. I prime the motor and it picks up speed again for a while, and goes right back to slowing down again. If I don't prime the motor it slows down to Idle speed, have any idea's as to what I should be checking? Thanks Joe
