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  1. #1
    Supreme Mariner Boomyal's Avatar
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    Default Ignition point gap?

    In the absence of a manual, what might be a safe generic point gap setting. This is for a 12 v, 4 cylinder industrial flathead engine in a 1962 Hyster Forklift.

    Currently, with a relatively new set of points installed by a 'professional', I cannot even slide an .011 business card between the points. This might account for why it is hard to start.

    I checked the plugs. (this is a propane fired unit) and they were clean. I widened the plug gap from about .025 to .034 and it finally started right up.

    I am actually in the process of installing a Pertronix Ignitor but I will save the points and want to know how to set them up should the need arise in the future.

  2. #2
    Moderator Bob_VT's Avatar
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    Default Re: Ignition point gap?

    Business card!! I used to use a matchbook cover which was over twice as thick. I was going to say start at .030.
    This is a great link to boat specifications http://boatspecs.iboats.com/
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  3. #3
    Commander MTboatguy's Avatar
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    Default Re: Ignition point gap?

    I was going to suggest .035, but it sounds like you stumbled upon it yourself, run it for a while at that setting then check the points to check for pitting and burning.

  4. #4
    Admiral j_martin's Avatar
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    Default Re: Ignition point gap?

    Not knowing the distributor, I'd set the rub block down on the cam at a low spot, turn it to a high spot, measure the gap, then set it to 1/2 of that, or .010" less than the throw if the total throw is less than .035"

    Jeep 4 banger is .020 (from memory)

  5. #5
    Admiral
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    Default Re: Ignition point gap?

    +1 on the match book point gap thing, paper match thickness on the plug gap.


    Holy crap, I am a child of the 60's!!
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  6. #6
    Supreme Mariner Boomyal's Avatar
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    Default Re: Ignition point gap?

    Hmmmm? I rounded up two match books. One was from Los Angeles, the other from a hotel in Mexico. The LA book measured .008 thick, the Mexican book measured .012 thick.

    As it has been decades since they gave you a match book when you bought a pack of ciggies from a vending machine, I think they have gotten thinner. But at least the Mexican one was thicker than the business card I tried to insert between the points.

  7. #7
    Captain Tim Frank's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by Boomyal View Post
    In the absence of a manual, what might be a safe generic point gap setting. This is for a 12 v, 4 cylinder industrial flathead engine in a 1962 Hyster Forklift.

    Currently, with a relatively new set of points installed by a 'professional', I cannot even slide an .011 business card between the points. This might account for why it is hard to start.

    I checked the plugs. (this is a propane fired unit) and they were clean. I widened the plug gap from about .025 to .034 and it finally started right up.

    I am actually in the process of installing a Pertronix Ignitor but I will save the points and want to know how to set them up should the need arise in the future.
    You might be further ahead using dwell angle ~ 52-58 degrees.

    "A tachometer/dwell meter is very useful for the tune-up procedure. The six (6) cylinder engines should be set for 35 degrees of dwell angle and the four (4) cylinder engines should be set for 55 degrees of dwell angle. If necessary, readjust the points to achieve this dwell angle. Accelerate the engine up and down quickly. If the dwell angle varies more than four (4) degrees for the six (6) cylinder engines or six (6) degrees for the four (4) cylinder engines, change the points. This test indicates a weak point spring."

  8. #8
    Senior Chief Petty Officer jimr's Avatar
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    Default Re: Ignition point gap?

    I had an old guy tell me once that for a base line set points at half of what the plug gap was. I don't know how true that is but that man could make an old car purr
    ASE MASTER AUTOMOTIVE AND MEDIUM/HEAVY TRUCK TECHNICIAN
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  9. #9
    Master Chief Petty Officer dwco5051's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by jimr View Post
    I had an old guy tell me once that for a base line set points at half of what the plug gap was. I don't know how true that is but that man could make an old car purr
    Heard that often 50 or so years ago. The other rule was set the points with a matchbook cover and the plugs with a worn dime. Thought it was really neat when I got my first dwell meter and could set points with an allen wrench on those old GM distributors.

  10. #10
    Commander MTboatguy's Avatar
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    Default Re: Ignition point gap?

    I just find it great to actually be in the company of people who know what points are!


  11. #11
    Supreme Mariner bruceb58's Avatar
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    Default Re: Ignition point gap?

    Set with a dwell meter like Tim said. Around 60 degrees for a 4 cylinder engine.
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  12. #12
    Supreme Mariner Boomyal's Avatar
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    Default Re: Ignition point gap?

    I have a near virgin Sears Engine Analyser that my mother bought my dad back in the '60's. It has a wide sweeping analog display that has umpteen different levels of functions displayed. There are also just as many different buttons, levers and switches so that you know which function you want to read on this sweeping arc.

    I'm sure that there is a function on it to read dwell. However, my gap question started out to supply future knowledge should I have to re-install the points.

    I am in the process of installing a Pertronix Ignitor on this old forklift to make it easier to start after sitting idle for weeks at a time, in a cold damp storage environment.

  13. #13
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    Default Re: Ignition point gap?

    Quote Originally Posted by MTboatguy View Post
    I just find it great to actually be in the company of people who know what points are!

    x2 Anybody remember the trick of loading a condensor with a charge and playing catch? Here catch...
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  14. #14
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    Default Re: Ignition point gap?

    Boomyal, my only question is: if you have calipers or micrometers to measure the thickness of various types of paper, why don't you have feeler gauges?
    Mike
    Ol' Stonebreaker

  15. #15
    Moderator achris's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by BlkY2k View Post
    x2 Anybody remember the trick of loading a condensor with a charge and playing catch? Here catch...
    I remember that game! Or putting a electrolytic capacitor across a power socket. When someone turned the power on the cap would either explode or release copious quantities of acrid smoke.... Fun days.... HSE have killed those games...

    If it is a Continental:
    F-4140 and F-4162
    firing order 1342 plug gap .025 breaker gap .022 timing 9 btdc@flywheel valve clearance hot .014 intake and exhaust.
    F-4140 bore3 3/16 stroke4 3/8 comp6.99 140 cu in piston displ.
    F-4162 bore3 7/16 stroke4 3/8 comp7.02 162 cu in piston displacement
    4 quarts oil
    oil press 35-40
    F-4140 52 brake hp @3200 rpm .lb ft torque 108 @ 1600
    F- 4162 58 " " @ " rpm. " " " 122 @ "

    HTH,

    Chris.........
    The world takes on a whole new perspective when viewed from 100' below...



    1972 Bertram 'Bahia Mar' 20
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  16. #16
    Supreme Mariner Boomyal's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by mla2ofus View Post
    Boomyal, my only question is: if you have calipers or micrometers to measure the thickness of various types of paper, why don't you have feeler gauges?
    Mike
    Fair question mla2ofus 'cause the forklift is in a 40 ft container, about 5 mi's from my tool suppy, in my garage. As it was, I loaded a whole box of different tools when I set out on this project, just that a feeler guage was not amongst them.

    I carry a digital vernier in my van.

  17. #17
    Supreme Mariner Boomyal's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by achris View Post
    I remember that game! Or putting a electrolytic capacitor across a power socket. When someone turned the power on the cap would either explode or release copious quantities of acrid smoke.... Fun days.... HSE have killed those games...

    If it is a Continental:
    F-4140 and F-4162
    firing order 1342 plug gap .025 breaker gap .022 timing 9 btdc@flywheel valve clearance hot .014 intake and exhaust.
    F-4140 bore3 3/16 stroke4 3/8 comp6.99 140 cu in piston displ.
    F-4162 bore3 7/16 stroke4 3/8 comp7.02 162 cu in piston displacement
    4 quarts oil
    oil press 35-40
    F-4140 52 brake hp @3200 rpm .lb ft torque 108 @ 1600
    F- 4162 58 " " @ " rpm. " " " 122 @ "

    HTH,

    Chris.........
    Thanks Chris. It has everything but the plug gap. They looked pretty puny when I pulled them. Considering that I am installing a Pertronix Ignitor, I set them at .034. Just a guess, however.

  18. #18
    Moderator achris's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by Boomyal View Post
    Thanks Chris. It has everything but the plug gap. They looked pretty puny when I pulled them. Considering that I am installing a Pertronix Ignitor, I set them at .034. Just a guess, however.
    Quote Originally Posted by achris View Post
    firing order 1342 plug gap .025 breaker gap .022 timing 9 btdc@flywheel valve clearance hot .014 intake and exhaust.
    Yeah, sorry I missed that too.... Had to re-read it a few times before I saw it....
    The world takes on a whole new perspective when viewed from 100' below...



    1972 Bertram 'Bahia Mar' 20
    2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
    **
    Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
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  19. #19
    Moderator Bob_VT's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by MTboatguy View Post
    I just find it great to actually be in the company of people who know what points are!

    Hmmmmmm so which is vintage????? Us or the points!!!
    This is a great link to boat specifications http://boatspecs.iboats.com/
    Please, shop iboats first!!


  20. #20
    Moderator achris's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by Bob_VT View Post
    Hmmmmmm so which is vintage????? Us or the points!!!
    Sadly, both....
    The world takes on a whole new perspective when viewed from 100' below...



    1972 Bertram 'Bahia Mar' 20
    2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
    **
    Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
    **
    Member of the month - April 2013. http://www.iboats.com/blog/achris-member-of-the-month/

  21. #21
    Supreme Mariner Boomyal's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by achris View Post
    Yeah, sorry I missed that too.... Had to re-read it a few times before I saw it....

    Yeah, I missed that too. .025 is probably what they were set at but the spark was anemic with the original point/condensor setup. I widened them to .034 even before I installed the Pertronix.

    When I put the pulled plug into the boot and grounded it, the .034 threw a much better spark. I did not re-test it after I installed the Pertronix. I just figured if it threw a better spark before, it had to be good with the Pertonix. The proof was in the pudding when I fired it up after install. It never started so quick.

  22. #22
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    Default Re: Ignition point gap?

    I was told ten thousands. If you dont have a gauge use a thin dime. If you dont have a thin dime use a nickel and 5 pennies.
    rebuilding 3 classics
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  23. #23
    Supreme Mariner Boomyal's Avatar
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    Default Re: Ignition point gap?

    Quote Originally Posted by Lyle29464 View Post
    I was told ten thousands. If you dont have a gauge use a thin dime. If you dont have a thin dime use a nickel and 5 pennies.
    If I remember correctly, one thin dime used to get you a long way! Hey buddy.....

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