Could be a lot of things. You need to get more specific. Did you have fresh fuel? Did you pull the plugs to see if they were fouled? Did you fun all the fuel out last year and use Stabil? Do you have spark to all the cylinders? As you can see you need to post as much info as you can.
Hi Fireman, the boat is brand new..only 6 hours on her. It has fresh gas..its second tank. It ran fine during the day, just poped when I shut it off to let the kids swim. Starts right back up, and it did it once more, but then not again.
An 18' boat with a four-popper??? My sympathies!<br /><br />Still under warranty? Have the dealer check timing, idle speed and mixture. They should have done that in the first place! Actually, come to think of it that's not a warranty issue...just poor setup by the dealer. They should fix the problem for free. If they'd have done their job, it wouldn't have been a problem in the first place. Did you get a pre-delivery checklist when you bought it? That's pretty much mandatory. It would show that the boat was thoroughly checked-out before they handed it over to you. Lack of one would tell me they didn't do squat.<br /><br />I see you're from Wisconsin. Is it safe to assume you're not IN Wisconsin? Sometimes significant changes in climate and altitude will affect performance with carbureted motors. You might need to get it tweaked for your current circumstances.<br /><br />(I'm assuming you have a 3L sterndrive. You might get more responses if you post in the "I/O or Inboard Engine" category. Maybe one of the moderators will move it there.)