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How to start generator with battery (self start) with ignition.

  1. Jul 13, 2012 #1
    Hi to all, I have generator 3500watts (Made in China). it has pull start with rope. and i want alternate start with self start....! i hope you understand what i am talking about. Thanks in advance.

    what accessories or tools required?

    how to do?

    how it works?

    guys i am not engineer please guide me, complete instruction please and thanks to all who will respond me.
  2. jcsd
  3. Jul 13, 2012 #2


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    This would probably use an alternator similar to the ones used in cars. Does it?

    The alternator is an AC generator, so you can't run this on DC to work as a starter motor.

    So, you might have to find some way of mounting a starter motor on the "pull to start" pulley.

    This is a serious project, though, and you might be better off selling the generator you have and buying one with an electric starter built in.
  4. Jul 13, 2012 #3
    yeah its big project thats why i am asking for the help here...! what things required? how to do? how it works please....! in the market one person asking for the 45pound...! i want to do at home please
  5. Jul 13, 2012 #4


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    Electrically, it is not difficult. You apply power to the starter motor and it turns the engine.

    It also has to disconnect the starter motor when the engine starts or the starter motor will be driven by the engine.

    The difficult bit is the mechanical mounting of the starter motor on the pulley.

    So, you would need to examine the generator to find out how you would mount the supports for the starter motor. There may be bolts already there that you could use or you may need to drill holes or weld something on. That bit is up to you.
  6. Jul 13, 2012 #5
    starter motor is must required??

    it can't be run only on 12v battery??
  7. Jul 13, 2012 #6
    how are you..! i hope you are fine...!
    can you come on skype so in that way i can show you the generator with webcam..!

    my skype id: kamran.virk2

    add me on skype and i am online on skpe waiting for you...!
  8. Jul 13, 2012 #7


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    Sorry, I can't do that.

    You probably need to get local help with your generator.

    We had a Forum expert on this stuff, but he is no longer with us, unfortunately.
  9. Jul 13, 2012 #8
    owh...! ok no problem, is there any option on this forum site for voice chat?? of coursr Not...! that is why skype...! for voice talk..!
  10. Jul 13, 2012 #9


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    I just noticed this.

    I'm assuming this is a gasoline (petrol) engine powered electrical generator.

    How else would you start it except with a starter motor?
  11. Jul 13, 2012 #10
    i an expecting to start it with battery, with ignition...! it might be wrong..,! actually i dont what exact things are require for it and even i dont how it works, i am just expecting....!
  12. Jul 13, 2012 #11


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    You have to actually turn the motor to start it and you need a starter motor to do this.

    It just does what you do now with a starter rope.
  13. Jul 14, 2012 #12
    yes i need to start motor without pulling rope....! yes i need starter motor, how to do??
  14. Jul 14, 2012 #13


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    The requirements for a starter motor and a generator are very different. In all conventional systems, you have to use two separate units. The starter motor needs a very high power but only operates briefly and needs to be a DC motor (to work from the battery). You need to engage the starter (mechanically) for starting and then disengage it when the engine is running. A ring gear on the flywheel is normally used and a pinion on the started motor is thrown onto it with a solenoid for starting. This is not something you can just make up yourself.
    There used to be a horrible device called a Dynastart, which was a DC motor which also acted as a dynamo, when the engine was running. It was rubbish as a generator and would only start small engines. On some hybrid vehicles, they use a modern and much improved version of this. Definitely too expensive for a home project! and compatibility would probably be a problem. Citroen have a 'stop start' system which does this, I believe, as an example.

    For a light power application (which yours appears to be) you could, maybe, use a DC motor and a dog, to engage with your existing pull cord pulley. This would need to be allowed only a few turns of the motor and then stop and release the pawl. Unless you got the design just right, you could easily shear off bits on this starter mechanism as it's only designed for a 'feeble' hand-pull.
    If you aren't highly competent with workshop tools then you should really think in terms of buying the right thing. Probably cheaper in the long run. There are plenty of battery start generators on the market.
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