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78 Evinrude 70HP cranks but won't start

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  • 78 Evinrude 70HP cranks but won't start

    Hello, I bought a 64 MFG 17' VHULL w/ a 1978 Evinrude 70HP the end of last season. I took it out for a test run before buying it. It started up fine first turn. Last fall I fogged the engine. This spring in prep. I changed the plugs and oil. Last week, took the boat to the ramp and took a few tries to start but we got it running and well. So, we took it to the slip for the season. Next day, can not get her started. She cranks but won't turn over. Tried new gas, put old plugs back in. Noticed that the gasket leaking fuel on the intake. But can that cause her not to start? Possibly the choke is not getting enough suction? Please help!

  • #2
    Re: 78 Evinrude 70HP cranks but won't start

    Try it while plugging the lanyard in and out a couple times. These emergency lanyards can get a bit of moisture in them, and wuit working altogether.If no good,take some WD40, and shoot about a 4 second blast directly into the carb, and try to start it.If it sputters at all, your problem is fuel related in some way.If not, it is ignition in some way.More particulars,and a process of ellimination are in order for now.
    "Did you hear about the guy whose whole left side was cut off? He's all
    right now."


    • #3
      Re: 78 Evinrude 70HP cranks but won't start

      12Footer, ^5dusle,Please keep your questions on the same topic in the same post and don't double post. Makes it alot easier to compile the responses that you already have. Give it some fuel, wd40 or premix or anything that might make it pop. If not post back, might be electrical. Gotta start somewhere. Mike


      • #4
        Re: 78 Evinrude 70HP cranks but won't start

        You didn't drain the carbs after last season, did you? That is a very important thing to do and saves you a lot of trouble. ...next time.Take a look inside the float bowls an look for dirt, water and some unindentified "slime"./Bear


        • #5
          Re: 78 Evinrude 70HP cranks but won't start

          Thankyou for all your help. I should let you all know that I have also posted a topic titled "1978 Evinrude 70HP won't start". Sorry, I am new to the board and didn't realize that I could keep posting to the topic. Since this one was posted first I have requested any replies be posted here. Now, I am a bit confused as to what the lanyard is. However, I plan to spray the premix into the carbs and see what happens. I spoke to a mechanic the other day he told me that I also could try and hold my hands over the three carbs while trying to start it and she should start right up if it is a fuel problem. He also told me to pull the carbs out and clean them thoroughly. Do you reccomend I try and use the premix first to spray into the carbs, then if that works I clean the carbs out? Again, Thanks for your help and please continue to posting replies to this topic.


          • #6
            Re: 78 Evinrude 70HP cranks but won't start

            Also,To give you a rundown of the boat history.Bought the boat at the end of last season. Took it for a test run out on the Bay, Started right up several times. I ran the boat out of gas as pulling it onto the trailer (to answer your question about draining the carbs) Winterization included pulling the plugs and spraying fogging oil in, then replacing old plugs. Added fuel stabilizer to each of three six gallon tanks. Two weeks ago, I put new plugs in, Changed the lower end oil. Over the weekend I started her up with muffs on, she started fairly easily two or three cranks (I did notice alot of white smoke). Then I took her down to drop in the water, coming off the trailer she took a little longer to start but did and ran well. I took it to the dock and put the old plugs back in and got a fresh six gallon tank of gas. She started up, still a bit hesitantly. Then shut it down and started right back up immediatetly. So, next morning I come down to the dock with fishing rods and tackle and she won't turn over. I noticed that the gasket is leaking fuel from the intake. Now, I have a new gasket to put on, and will take the advice of you kind gentlemen to spray the premix into the carbs. Thanks, I will keep you posted..


            • #7
              Re: 78 Evinrude 70HP cranks but won't start

              Ahoy, I have pinpointed my problem. A neighbor of mine has shown me that I do not know how to start the boat properly. Apparently, using the choke too often has been flooding the engine. Not sure exactly how to use the choke, but it is starting now. Thanks again for your help.