I'm not sure if it's in the right section but anyway I have a sea master 21 with an Enfield drive, I think the boats from around the early 80's. Basically when ever I put it into gear it pops out, it goes into gear and from tick over up to full revs it jumps. I thought it might've been the cable as it seemed a bit short but I've replaced the cables and still the same result. I had a mechanic look at it briefly and he reckons it could be the gear selector that's worn out. Any ideas on what it could be and also where I could get a second hand parts for this model type from? If it is the gear selector, would I need to change the whole drive leg or just that part? I really hope someone can help me as this has already caused me so much stress!