L-head Dwell

Discussion in 'Flat Fender Tech' started by DanStew, Jun 14, 2017.

  1. Jun 14, 2017
    DanStew

    DanStew Incorrigible. Staff Member Sponsor

    Lexington, South...
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    Is it gonna be bad to run dwell at 23 degrees?
    I have the points set with the proper gauge. i guess i could go a touch lower with the point adjustment, but if i dont adjust the points going to burn out quickly?
     
  2. Jun 14, 2017
    PeteL

    PeteL Member Sponsor

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    A minor difference in dwell is probably not significant to point life. Some folks used to set the points a tad wide on the theory they will close up as the heel wears. (You did grease it, right?)

    Realize however as dwell changes, so does timing, since the points will open earlier or later in the cycle. Again a minor factor in vehicles like ours.
     
  3. Jun 14, 2017
    DanStew

    DanStew Incorrigible. Staff Member Sponsor

    Lexington, South...
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    ok. i will probably not touch a thing. i have it running pretty good right now. Still some popping at the tailpipe. Not so much backfire, but just sound a bit uneven. Might be a blocked muffler.
     
  4. Jun 14, 2017
    PeteL

    PeteL Member Sponsor

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    Mine always sounds like that.
     
  5. Jun 14, 2017
    Glenn

    Glenn Kinda grumpy old man Staff Member Sponsor

    Apopka, Fl
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    I've heard others say that too, but I can't wrap my head around that. I know the points won't open as far when the rubbing block wears but won't the initial rubbing block contact point on the distributor lobe be the same?
     
  6. Jun 14, 2017
    PeteL

    PeteL Member Sponsor

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    No. Both the moving and the stationary side of the point set is involved in adjustment.

    If the gap is set larger by relocating the entire points assembly, the heel rests nearer the distributor cam when closed - and so does the passive side of the electrical contacts. Therefore as the cam lobe approaches, it strikes the heel and opens the points sooner as well as wider.

    Or visa-versa - if the heel wears away, the opening is delayed since the cam reaches it later.
    (y)
     
    Last edited: Jun 14, 2017
  7. Jun 15, 2017
    Mark Wahlster

    Mark Wahlster Member

    Silverton, OR
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    HUH? dwell on a 4 cylinder engine should be around 45-46 degrees
     
  8. Jun 15, 2017
    PeteL

    PeteL Member Sponsor

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    "Cam angle" is specced at 42º in my FSM. Maybe his meter is set to 8-cylinder?
     
  9. Jun 15, 2017
    Howard Eisenhauer

    Howard Eisenhauer Super Moderator Staff Member Sponsor

    Tantallon, Nova...
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    That was my first guess.
     

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