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  • Cranks but does not start

    Greetings:
    My 60 Tbird is driving me crazy. I parked it several months ago and now it will not start. It cranks fine but I have no spark to the #5 plug. I put starting fluid in it , but still get no fire of course. I can see the fuel pump working (glass filter). So I have an ignition problem, duh? I checked the battery wires and the wires to/from the starter relay. All seem good. I have replaced the following: coil, points, distributor cap, rotor, condenser and high voltage lead from coil to distributor. I also check distributor ground and wires from coil to distributor. I found that either my ignition switch is bad or the resistor wire from the switch to the coil is bad as I am not getting any power to the positive side of the coil when the ignition switch is in the run position. I decided to see if I could get the car started by bypassing this problem - so I ran a jumper lead directly from the battery positive to the + side of the coil. Cranked it, but still no spark. I attempted to set the points correctly, and noticed that the distributor cam is turning when I try to start it so think this means that my timing chain is not broken. Raised the contact on top of the rotor to make sure it is touching the rotor cap. What else is there to do???? I really feel stupid as there is probably some simple thing I have overlooked. I thought I understood this car?? Is there something in the bad ignition switch or the resistor wire which is required to function properly to fire the engine? Don't know why. Is there something that prevents my direct wiring from the battery to the coil from working, i.e. starting the car? I realize that one or more if my replacement parts might not be good (Chinese manufacture?) but I have tried to swap parts from another running 60 Bird I have. Also don't seem to be getting any spark jump across points. Any thoughts would be appreciated. Am planning to install an electronic ignition on the car ( Permetex Ignitor) but feel I need to solve this problem first! Really feel stupid....Thanks for any thoughts or help.

  • #2
    Could be minor corrosion on the points.

    Comment


    • #3
      When you say you don't have spark to the #5 cylinder does that mean you have spark to all the others or you don't have any spark at all. When you say you replaced all the ignition parts does that mean you replaced them after the problem happened or before. The most common cause would be the condenser if it's not the points being corroded as Carl mentioned. I would change the condenser first before you drive yourself crazy doing too much troubleshooting. I've gone through the same thing after putting in a "known" good condenser that turned out to be bad after all. You did right by connecting a wire directly from the battery to the coil. This eliminates the solenoid as a possible problem. The resistor wire only comes into play when the key goes from Start to On. In Start the solenoid sends 12V to the coil.

      John
      John Pizzi - Squarebirds Administrator

      Thunderbird Registry #36223
      jopizz@squarebirds.org 856-779-9695

      https://www.squarebirds.org/picture_gallery/TechnicalResourceLibrary/trl.htm

      Comment


      • #4
        You have done a lot of the same trouble shooting I would have done, and it's hard to figure that you still don't have spark. After reading everything you have done, I started wondering if you have a good ground to the engine? You can have all the voltage in the world going to the plugs, but if they do not have a good ground, they will never spark. More thinking, if you were lacking a good ground, why would the starter turn the engine. Have you checked to see if you have spark out of the high voltage wire coming directly out of the distributor? That would tell you have spark, but it is not getting out of the distributor. If you replaced the coil, are you sure it is wired in correctly? There is also the possibility that you got a bad coil when you replaced it. God's given is rule is "just because it's new, doesn't mean it is good".
        Nyles

        Comment


        • #5
          I replaced all the parts mentioned after it would not start. I did not check for spark to each spark plug but as it did not fire at all when I put starting fluid into the carburetor, I am assuming that most if not all of the plugs have no spark. I did take the high voltage line off the coil and held it about 3/8 of an inch from the head and cranked the engine. Saw no spark jump. I was concerned about the ground to the distributor so I took off the rotor cap and ran a test light from the points base to the battery positive. I got a positive light, so assume that the distributor is correctly grounded. I have only tried one set of new points in the distributor since the problem began. As the points are new, out of the box, don,t think corrosion is the problem. I guess the new points could be defective??? As I am now running a hot lead directly from the battery to the positive side of the coil, I guess the problem has to be in the coil or distributor. I did bench test the resistance (ohms) in the coil and condenser I am using and they both tested within spec. Next step unless I hear another idea is to buy another set of points. After that, look for a cliff to push the car over..........

          Comment


          • #6
            Since you are not getting a spark when you take the coil wire and hold it close to a ground, that basically leaves 4 things. The coil, the high tension coil wire, the points or the condenser. Most people think a spark plug fires when the points close, but this in not correct. The spark plug will fire when the points OPEN. So since you already have 12V to the positive side of the coil, connect a jumper wire from the negative side and momentarily touch it to a ground. When you break the ground the high voltage coil wire should spark when put within an 1/8" of a good ground. If you get a spark, the coil and wire are good. If not, one or the other is bad. Give this a try and let us know what happens.
            Nyles

            Comment


            • #7
              Don't forget the coil-to-points wire. I've had them fail. It flexes every time the plate advances the spark.

              Comment


              • #8
                I like the explanation Nyles gave. Let's take this one component at a time starting with the coil. Pull all the wires off of it.
                Use a spark plug wire with a spark plug attached, laying on engine metal. Shove the spark plug wire into the coil's tower,
                Connect a +12 volt wire to the coil POS (+) terminal.
                Connect a test wire to ground and simply 'brush' the other end of the test wire to the coil's NEG (-) terminal.
                As Nyles said, every time the negative (test) wire disconnects from the coil's post, you should hear a snap and see a bright blue spark at the spark plug. If the spark is orange, you have a weak coil.

                If you're not getting a spark, replace the coil. - Dave
                My latest project:
                CLICK HERE to see my custom hydraulic roller 390 FE build.

                "We've got to pause and ask ourselves: How much clean air do we need?"
                --Lee Iacocca

                From: Royal Oak, Michigan

                Comment


                • #9
                  I performed the test that Niles suggested. Hot lead from battery to + (Bat) on coil. Removed wire from top of coil to distributor at distributor. Held it approximately 1/8th inch from block ground. Then I put a jumper wire on - (DIS) terminal of coil. I did not disconnect normal wire from coil to distributor. When I touched my jumper wire to the block (ground) I got a spark. When I moved jumper wire off the block (ground), I noticed a small spark jump the 1/8 inch gap between the coil high voltage wire and the block. The spark did not appear blue but it was clearly evident. Guess this mean that my coil and the wire from the top of the coil to the distributor are OK.... (?) Guess I need now to concentrate on the distributor, points and condenser as the source of my problems. I will also try Dave's confirming suggestion with the spark plug to verify the strength of the coil. Let you all know. Progress??? Thanks everybody for the help and suggestions.

                  Comment


                  • #10
                    Since you determined the coil is good, next check the wire from the distributor to the points AND the short ground jumper on your points plate. You may very well find that the condenser is bad. In normal operation, spark happens when the points open (whether the condenser is there or not as you proved). So, energize the coil then open the points. If you get a spark with NO condenser you will know the condenser is bad. If you get no spark at all, something is either grounding the wire coming from the coil or the wire is simply open.

                    I use simple tools to check wires, like a test light and a jumper wire. (A meter is helpful too.) With the key turned 'on', open the points and use a jumper wire between ground and the points. Again, I use a spark plug wire shoved into the coil tower with a spare spark plug laying on the engine. You should hear it 'snap' with each spark. Troubleshoot from the problem back to the source. - Dave
                    My latest project:
                    CLICK HERE to see my custom hydraulic roller 390 FE build.

                    "We've got to pause and ask ourselves: How much clean air do we need?"
                    --Lee Iacocca

                    From: Royal Oak, Michigan

                    Comment


                    • #11
                      Thanks Dave for the organized approach. I feel like I previously performed most of the component checks needed to troubleshoot the problem, but not in such an organized and backtracking manner as you have proposed. Maybe I missed something obvious. I will proceed with your suggestions and report the results. One side question first. I bench checked 3 different coils I have. I noticed that when I simply apply 12+ volts to the positive terminal of the coil, I get the same 12 volts out of the distributor terminal and the top (high lead) terminal of the coil. (Maybe the input 12+ volts is very slightly reduced) Is this normal? I thought that the internal workings of the coil is two separate "windings" in an oil bath. Why then the same voltage out? "Just trying to understand the system" Again thanks for the help. Will be in touch.

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