I am looking for a kicker motor for my 15.5' fiberglass runabout. The main motor is a 50 hp Mercury (2 stroke 4 cylinder). I want the kicker for fishing and as a get home motor in case the 50 hp fails. <br /><br />I don't know the weight of the boat but it runs pretty well with the 50 hp. With 2 passengers it will go 24 knots at 5400 RPM.<br /><br />Since the kicker will not plane the hull I will be limited to hull speed I am thinking that a 5 hp 2 stroke would make sense. A 5 hp will be under 50 lbs and should push the boat at 4-5 knots. I am not too keen on 6-8 hp because they will add weight, will not plane the hull and will be a tight fit on the transom. I don't have room for a kicker bracket.<br /><br />I have been looking at a new 1998 5 hp 2 stroke (single cylinder) Johnson. It takes a 50:1 fuel - like the 50 hp Merc. The dealer wants US$710. <br /><br />Will the 5 hp Johnson work with my mercury tanks? <br />Do I need to rig up a special fuel line? <br />Is the 5 hp Johnson a good motor? <br /><br />I have also been looking at a 1980 4.5 hp Mercury. The asking price is $250. The motor is in pretty good shape. I have checked out parts availability at the http://www.mercurymarine.com. It looks like quite a few parts are still available. Mercury does not sell propellers for this outboard anymore (the prop that's on it is in good shape). Is there anywhare I can buy a spare prop for this motor? <br /><br />I am tempted to go with the 4.5 mercury if I can get it for $200 or so. <br /><br />Any thoughts or suggestions would be greatly appreciated.<br /><br />Thank you,<br />Russell McPherson