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  1. #1

    Speedster 150 rough idle

    I took my boat out this past weekend for a quick ride (after months of sitting in my garage) and i noticed the boat running a bit rough, idle was not steady and the RPMS would jump a little at higher speeds. I know is not the washers becuase I had them replaced plus after a while the boat was running mostly normal. My question is, could this be bad fuel (the boat was sitting in the garage for few months(, bad spark plugs???? Like I said, after a like a half hour the boat was running normal with little hesitations here and there...but by the end of the day ot was running fiine. I just want to make sure that is not something electrical or major...

    Thank you all....


  2. #2
    Doo It Till It Hurts! holdnon72's Avatar
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    Did you forget to add the fuel stabilizer before you stored the boat away? If so, that would explain your problem....

  3. #3
    I did not winterize my boat since I live in "always hot" Florida and I did not add anything to the fuel...F!#$#%

    Can the fuel Stabilizer be added now or I should just burn that fuel.

    I usually don't winterrize my boat since is mostly hot all year around here FL and I usualy use the boat all year around too,,, this year it was the first year that the boat sat in the garage for for more than 3 months.

    Thank you for your help...

  4. #4
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by Rspeed View Post
    I did not winterize my boat since I live in "always hot" Florida and I did not add anything to the fuel...F!#$#%

    Can the fuel Stabilizer be added now or I should just burn that fuel.

    I usually don't winterize my boat since is mostly hot all year around here FL and I usually use the boat all year around too,,, this year it was the first year that the boat sat in the garage for for more than 3 months.

    Thank you for your help...
    Fuel stabilizer won't undo degradation of the gasoline. One thing gasoline does when it degrades is lose octane. My suggestion is to fill it with premium fuel to boost the average octane in the tank, and then burn through it.

    Fuel stabilizer doesn't hurt performance, so there is nothing wrong (other than the cost of the stabilizer) with adding it to every tank filling, or at add it least when you suspect you won't be using the fuel within the next few weeks.

    Gasoline starts to degrade after about 30 days, especially if it has Ethanol. How fast it degrades depends on a number of factors, including temperature.

    Ethanol fuels have the added problem of phase separation, where the ethanol in the fuel absorbs water, then drops out of the fuel blend and settles at the bottom of the tank (where the fuel pump intake is located). This phase separated ethanol+water junk doesn't burn properly in the engine, so you really want to avoid moisture in the fuel tank if you are using ethanol blended fuel.

    One way to reduce moisture inside the tank is to store the boat with the tank full, which reduces the air volume inside the tank. Stabilizers seem to have almost no effect on preventing phase separation - all you can do is try to keep moisture out of the fuel tank.

    Also, if phase separation happens, the remaining gasoline has lower octane than it should, which also is no good for the engine. If you have phase separated fuel in your tank, it needs to be pumped out, the tank cleaned, and fresh fuel purchased.

    Where I ride, I mostly purchase premium grade gasoline, from brands that do not put Ethanol in the premium grade. Then at least I don't have to worry about phase separation. All the regular grade fuel in my region includes ethanol

    I often add stabilizer to the tank, unless I am sure I am going to be refilling it again soon. I typically fill my tank on the way back from the day's riding, so the fuel tank is stored full, ready for the next time.

  5. #5
    Doo It Till It Hurts! holdnon72's Avatar
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    If I were you I would drain all the fuel from the tank. Just remove the large fuel hose from the top of the tank. Use one of those hand pumps and pump all the fuel out of the tank into a gas can. Get out the most you can. Go to the gas station and fill up with the highest octane cas you can find. Sunoco Ultra would work the best. Then run the boat for a few hours out on the water. Goodluck

  6. #6

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    New plugs and new gas.

    I had the same type of problem on my Sportster 4tec.

    It ran good after it warmed up but rough when starting out.


    Plugs made the biggest difference.


    Joe

  7. #7
    Guys I just wanted to take a quick second and say thank you to everyone. With helped from the forum, I changed the oil and spark plugs on my boat and the things is "flying low" I took the boat out this weekend and it was running supper smooth and fast...

    Thank you all....love this [email protected]#$ng forum...

  8. #8
    Thanks a lot for the info, the plugs did it... running smooth now...

  9. #9
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by Rspeed View Post
    Thanks a lot for the info, the plugs did it... running smooth now...
    Glad to hear it is now running as it should.

    For the next time you suspect the boat will be sitting for a while, put some fuel stabilizer in the tank, and run the motor enough to get it circulated.

    And try to stay away from Ethanol blended gasoline, if it will be sitting in your tank for a while.

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