I've got a 2003 Bennington pontoon boat with a Mercury 50HP Bigfoot 4 stroke. I bought the boat about 3 years ago and it has always started fine. A month or so ago the engine didn't turn over, so I grabbed my jumper box and the boat started right up. I figured the battery was just shot, and we only use the boat about once a week so I've just used the jump box. Yesterday I hooked up the jump box and it took several tries before the engine would turn over. But when it did turn over it turned over just fine and engine started right up. Today I put a new battery in the boat and it didn't turn over. After playing with it for a little while I noticed that if I hold the ignition key in the start position, the engine will begin turning over after about 5 seconds and starts normally. It does this EVERY TIME. I can start it 20 times in a row and it ALWAYS does nothing for 5 seconds, then turns over normally and starts. I can also wait an hour between starts and it does the same exact thing. I completely cleaned the battery connections, and inspected the connections on the ignition switch and they look fine. I've worked on cars for decades so I'm very familiar with how basic starting systems work. It seems like if it was a bad solenoid it wouldn't turn over at all, and if it was a bad starter it would turn over slowly and unpredictably. Is there anything quirky about these motors that causes behavior like this? Thanks in advance for ANY help or advice! I don't want to just start changing out parts....
