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Discussion Topic:
weak spark?
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a4ty4d |
05-21-2011 @ 2:04 PM
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Member
Posts: 4
Joined: Feb 2011
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I have been having a hard time getting my engine started. When I think I got it licked my 40 3/4 tonner gets stubborn again and it just won't start, even with starter fluid. I can only think it is a weak spark. I am getting a spark from the coil and from the spark plug but both seem whimpy to me. Is the primary source of the spark at the coil? Could it be a generator problem? Does anyone have any thoughts? Thanks, John
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37RAGTOPMAN |
05-21-2011 @ 5:52 PM
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Senior
Posts: 1942
Joined: Oct 2009
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HI check the voltage before the resister and after, it should be 6 plus volts before and 3 1/2 volts after, you might have loose or dirty connections on you ign switch, do a voltage check on the system and let us know what you find, make sure to disconect the battery, clean all the terminals and make sure they are tight and then do your tests, hope this helps 37RAGTOPMAN
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supereal |
05-21-2011 @ 6:25 PM
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Senior
Posts: 6819
Joined: Oct 2009
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Try replacing the condenser. The problem you set out is a classic example of a weak or open condenser.
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alanwoodieman |
05-22-2011 @ 10:19 AM
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Senior
Posts: 864
Joined: Oct 2009
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weak spark is not a generator problem. Check voltage in the battery, should be over 6 volts (6.4), to quickly check the resistor, put a jumper on the posts of the resistor, if you get a better spark, then at least you have eliminated it. Next check the coil, is it an original type? change out for another, if no change then go to the distributor, chances are points are not opening corectly, run a picee of emery cloth over them to clean them, check the gaps of the points.Run a wire directly from the battery to the distribtor to eleminate wiring problems. Let us know what yours results are.
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supereal |
05-22-2011 @ 11:28 AM
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Senior
Posts: 6819
Joined: Oct 2009
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If you are going to dress the points in any distributor, use a point file. Emery or other material, such as sandpaper, will cause failure of the contacts as grit is deposited on the surface. Weak or absent spark in often caused by one of the two sets of points. One set "makes" the circuit, then hands it off to the second "break" set. If you believe that the distributor is faulty, send it to a shop with a machine to test and set it up. You may also try to shift the point plate by moving the timing slider on the side. Sometimes the spring loaded contact between the input terminal and the place is the cause.
This message was edited by supereal on 5-22-11 @ 11:35 AM
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