Engine turns slow, then gets faster. Any Ideas?

Discussion in 'Technical' started by ryanb, Jan 26, 2011.

  1. ryanb

    ryanb Member

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    I bought a freshly rebuilt 302 a while back and I dropped it into my maverick. It starts fine when it's cold but when the engine warms up it turns over really slow, then after a couple seconds it starts turning over faster. I don't know much about this engine, but it runs fine, and even when it does turn over slowly it starts up ok. Could it have to do with the compression ratio? Is it an ignition problem? It's got a pretty fresh starter, solenoid, cables, and it's got a good ground connection. The battery is fully charged, soon I'll be swapping in an optima. Does anyone have any idea what it could be?

    Thanks in advance,
    Ryan
     
    ryanb, Jan 26, 2011
    #1
  2. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Sounds like over advanced timing or heat soak into the starter/ Check your battery cable connections as well...
     
    Mavman72, Jan 26, 2011
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  3. 71gold

    71gold Frank Cooper Supporting Member

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    X2...:yup:
     
    71gold, Jan 26, 2011
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  4. darren

    darren Member

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    Pete beat me again. :huh: first thought was hot starter. Like Pete said bad connections can do that also.:):)

    You may need a heat shield on the starter.
     
    darren, Jan 26, 2011
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  5. Bryant

    Bryant forgot more than learned

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    another vote for over advance timing. what is it set to? at idle and at 3000 rpm
     
    Bryant, Jan 27, 2011
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  6. lynhrt210

    lynhrt210 Member

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    Thats what mine does too! Lol but I knew why already I need to get a heat sheild for my starter at work
     
    lynhrt210, Jan 27, 2011
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  7. 302-72-mav

    302-72-mav Member

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    not sure why but alot of mustangs do that cold or hot

    dont you think it could be that it gets easier because it's got the motor turning as fast as it can go after the first second or two ?

    i know when you have the timing to far advanced and the motors hot it wont want to turn much at all ?
     
    302-72-mav, Jan 27, 2011
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  8. Streamliner

    Streamliner Member

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    yep on the timing but a fresh motor will also be somewhat "tighter". especially when hot until things break in
     
    Streamliner, Jan 27, 2011
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  9. baddad457

    baddad457 Member

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    A starter with weak field coils will also do that. You say "fresh starter" as in freshly rebuilt ? Rebuilders seldom ever change the field coils and that's the most important thing to change. The hotter they get, the slower the starter will turn the motor
     
    baddad457, Jan 27, 2011
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  10. Demmitt

    Demmitt nutz and boltz

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    we need to know what comp ratio and what starter. :huh:
     
    Demmitt, Jan 27, 2011
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  11. injectedmav

    injectedmav Member

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    worn starter brushes and armature/drive end bushings are a possibility as well in addition to above. don't overlook the ground side. too many times have I seen a 2 or 4ga feed wire and a 6ga or smaller ground or one with bad connections.
     
    injectedmav, Jan 27, 2011
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