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  1. #1

    Angry Mercury 650 Thunderbolt wont start.

    New to boat motors- I have a 65 horse Mercury the serial shows that its made between 67-69. Its got new plugs- new fuel diaphragm- new impellor pump- new fuel tank and lines- new battery- you can hear the started spin it'll catch and turn over a few times but wont go- i heard it fire once or twice but then it would cut out... any ideas?

  2. #2
    Moderator Bob_VT's Avatar
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    This is a great link to boat specifications http://boatspecs.iboats.com/
    Please, shop iboats first!!


  3. #3

    Default Re: Mercury 650 Thunderbolt wont start.

    So I got it to run- but it sounded like idle when the throttle was full forward- sounds like the carb?

  4. #4
    Moderator Bob_VT's Avatar
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    Default Re: Mercury 650 Thunderbolt wont start.

    Manual........Compression test.... new plugs...... new impellar...... and re-build the carbs are the basics.

    Compression verifies what you are working with and you need to do a de-carb later when it is running.

    New plugs are a cheap investment to eliminate a problem

    New impellar because if it runs it needs to be properly cooled down

    Carb re-build because of the year and "unknown" history of the motor..... very good to do

    And a manual to tie it all together so you are not trying to do that stuff blind.
    This is a great link to boat specifications http://boatspecs.iboats.com/
    Please, shop iboats first!!


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