Mercury 110 9.8hp Top Speed?

Hey everyone! I am brand new to this forum and just bought my first boat last week. I picked up a 14ft Alumacraft jon with a 1972 (I believe) Merc 110 9.8hp. I took it out for the first time this Saturday for a test run, make sure the boat doesn't leak, etc. I used the fish finder speedo and a speedometer app I downloaded on my phone to clock the top speed. With just me in the boat (170 pounds), a battery, trolling motor and about a gallon of gas, my top speed was about 10 mph. This seems very slow to me. I have seen guys with this similar setup get 20mph or more. Do any of you have a comparable rig and if so what is your top speed? If anything it has me concerned that it's not running right or needs some adjustments somewhere. Anything I should look at? Thanks in advance for any comments!

Jason

The first thing I would look at would be the placement of the battery and fuel for balance purposes. Then I would check the height of the prop in relation to the bottom of the boat, and then I would experiment with the motors tilt. Does the motor run smooth and sound and act like it's running normal?

Hi there. ;-)


I had that same motor on a 12' mirro craft, though I never checked it's top speed I'd say it wasen't much more then 10/12mph.
I'm not sure you should be getting much more then what you are getting. Others with more experiance will chime in I'm sure.

Thanks for the replies guys. Regarding the battery and fuel tank for balance, I had the battery in the back left and fuel tank in the center because it fit better. I could move the gas tank to the right side and give a bit more balance. The tilt is down as far as possible so the motor is completely vertical. Having NO experience with these old outboards, I don't know what running "normal" should sound like but it did seem to vibrate and shake quite a bit at idle once I cranked it. When I was in gear at driving full speed it felt/sounded okay I guess. I don't have much to compare it to unfortunately. I just bought a compression tester so will check the compression tonight, also have new spark plugs on the way. maybe this will help some.

well, I just got home with my compression tester and pretty sure I found my problem. Both cylinders are at 45psi =(. I am really bummed. Is it unusual for both to be that low yet still equal? I tried them each a couple times and were dead on each try. The biggest question is, is there anything I can do to restore the compression short of a full rebuild? What options do I have?

Did you do your compression test with the throttle wide open? If not, then try them while holding the throttle wide open and see if you don't get a more suitable reading.