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    1941 Evinrude 3.3hp Sportwin fuel mix?

    I recently acquired an old pre-war opposed twin Evinrude, and I've been running 24:1 in it, same as my '57 5.5hp Fisherman. It seems to smoke a little, and I'm wondering if it's too rich or just a characteristic of a motor of this vintage. Also, would appreciate any additional info about this...
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    Racing exhaust stacks for small motors?

    Evidently, you used to be able to add racing exhaust to small hp motors for additional power - you removed the exhaust plate and bolted it on. Can anybody shed some light on this? Were these tuned exhaust setups like the type you can buy to put on small gas scooters to get more power/rpm's...
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    air-power outboards??

    In the Old Outboard Book, there are 3 diffferent brands of OB that used an airplane style prop to push a small boat Aerothrust, Air-boy, and Airdrive. The airboat motors I've seen are pretty big with full size airplane props and look like serious business, but these were evidently little...
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    big motor half throttle vs. small motor full throttle

    All conditions being equal, is it better to run a smaller engine at WOT or a larger engine at half-throttle for extended periods of time. Assume neither motor is being lugged, boat is cruising along on plane. Which is better for engine wear? Which is better for fuel economy? Both engines are...
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    questions about fuel pump vs homemade pressure tank

    I have a 1956 Evinrude Fisherman 5.5hp and a big heavy 6gal pressure tank which works fine. Would like to either l. convert to fuel pump or 2. Make a small pressure tank. I have successfully made a pressure tank out of a garden pesticide sprayer which works great as long as you pump it up...
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    More HP for little boat

    I have a 12ft Landau jonboat, originally rated for a 6hp motor, but have reinforced the transom (to take a little more weight) and want to stick a bigger engine on it for a little more speed. I am presently using a 5.5hp Evinrude or a 7hp Sears/Eska to push the boat; performance for either of...
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    Detuning for decreased horsepower??

    I have been examining the specs for the Merc 6hp and the 8hp motors and everything is identical except the power output. I have read that the "smaller" engine is a detuned version of the "larger" one. What is detuning and how hard is it to "un-detune" a detuned engine? I can get a real good...
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    3blade prop for old 5.5hp Fisherman?

    I am trying to get max top speed out of my old 1957 Fisherman (sounds crazy but it's become a challenge) So far, I have stripped 10lbs off the motor weight, built a small light 1gal tank for fuel, and now nothing remains but possible prop change. Motor presently has stock 2blade prop. I would...
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    dumb question about rusty gas tank

    I have an old Sears air-cooled motor with a Tecumseh powerhead and a built-in gas tank which was very rusty when I got it and after cleaning it out and using a fuel filter and cleaning the crap out of the carburetor many times since, it runs fine- until another little piece of rust lodges in the...
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    Simple homemade pressure fuel tank

    I don't know if anyone else has tried this, but I have an old 3hp motor that I had to throw the gas tank out due to rust and leakage, and it was either spend 50 or so bux for a new outbord fuel pump or devise a pressure type fuel tank like the old Johnrudes used in the 50's. Answer: a heavy...
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    Briggs&Stratton 5hp vs. Mercury 5hp

    I am curious to know if a 5hp Briggs&Stratton engine would be faster or slower than a Mercury (Nissan/Tohatsu etc.) 5hp on a lightweight aluminum jon boat, other things being equal. The Briggs is a 4 stroke and heavier than the Merc with its built-in fuel tank but other than that what would be...
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    old chrysler 3.5hp prop shaft seal

    I have an old chrysler 3.5hp air-cooled motor that needs a prop shaft seal. Model 303, about 1968 or 69, no water pump just a water scoop tube. It leaks all the L.U. lubricant out in 2 or 3 days due to a bad seal. Can anybody suggest a source for this part? Thanks.
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    1989 Force 50hp tach

    Hi: I would like to add a tach to my 1989 Force 50 (ModelB) and would appreciate advice as to what kind of tach to get and how to hook it up. Thanks in advance.
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    old Fisherman prop question

    My 1957 'rude Fisherman 5.5hp runs great, and pushes my little 12 foot aluminum pram between 15-17 mph GPS with just me in the boat. Would replacing the stock 2blade prop with a 3blade make it go any faster? Can you get a 3blade for this engine? Just curious and would appreciate any advice...
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    Bulletproof water pump?

    I have a 5hp British Seagull motor which uses a hard plastic 4bladed impeller (called a "rotor") that doesn't touch the sides of the housing and basically never wears out. Starting the motor dry won't hurt it. Motor can sit for 20 years and the impeller doesn't get hard and brittle and fly...
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    1989 Force 50 spark plugs

    I have a 1989B model Force 50 that calls for L76V gapless spark plugs. Motor runs fine most of the time, but has a tendency to load up and foul plugs after a period of slow running. After searching the forums here, I decided to try a pair of QL77JC4 regular type plugs based on what I read, but...
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    Force 50 sticky shifting hint

    Just a hint for all you Force 50 owners out there which I discovered today while trying to correct a shifting problem I never had before. Engine didn't want to shift into forward gear and I assumed it was adjustment problem or maybe lower unit problem. What I found out is that the place where...
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    rusty little gas tank

    I have an old Sears 7hp motor with an air-cooled Tecumseh (lawnmower type) powerhead. The steel gas tank is moderately rusty on the inside and even though I have flushed it out several times I still get lots of little flaky particles that clog the fuel line and fuel filter that I installed. I...
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    1989 Force 50hp powerhead or prop rated"

    Does anyone know if the horsepower of an '89 Force 50hp is rated at prop or powerhead? Engine was made by U.S. Marine.
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    British Seagull prop question

    Powerhead is single cyinder 2stroke, runs at 4000rpm, 3.1/l gear ratio, allegedly puts out 5.5hp at prop which is a 9inch 4blade. Motor is designed for heavy displacement hulls but I have it on a 12ft shallow draft aluinum planing hull. The only 2 ways I can see to increase hull speed is by...
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