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  • Engine: Engine miss diagnosis

    The car: 1955 Champion, 6 cylinder 3-speed overdrive. I almost didn't make it home today. My car started missing intermittently. It would run and quit running over and over in rapid succession and then clear up for a mile or two. When it was acting up, it would do it at a fast idle too. The carburetor is rebuilt and both the mechanical and electric fuel pumps are new. My guess is electrical but I don't know where to start checking. All of the tune-up items are only 3000 miles old and it has been running great. I hate to just throw new parts at it. Could the condenser or coil make it cut out intermittently like this?

  • #2
    Grab the coil with your hand.
    If it is too hot to hold on to, then the coil may be bad, or going bad.

    Sounds more fuel delivery than electrical.
    A bad coil usually turns off until it cools off. No erratic part.
    But contaminated fuel (water) could cause what you are describing.
    HTIH (Hope The Info Helps)

    Jeff


    Get your facts first, and then you can distort them as much as you please. Mark Twain



    Note: SDC# 070190 (and earlier...)

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    • #3
      Check your fuel filter. Sounds like its full of water or crud and leting a little fuel through intermittently.

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      • #4
        If there's no filter in front of the fuel pump, check it also. I've seen the valves completely plugged with grit and gunk.

        jack vines
        PackardV8

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        • #5
          Originally posted by PackardV8 View Post
          If there's no filter in front of the fuel pump, check it also. I've seen the valves completely plugged with grit and gunk.

          jack vines
          Jack, I have a new filter between the tank and electric pump and between the mechanical pump and the carb. The car sat for 18 years before I got it and has been running for about 3,000 miles. I did not drain the tank before I got it running but it has been running fine. I will drain the tank and change the front filter since the other one is only a month old. I think the water diagnosis is probably correct. What else could it be? Randy

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          • #6
            Randy -

            Replace the condensor inside the distributor.
            Clean the point plate, tighten the points well, tighten the condensor well.

            A coupla years ago, I had, by your discription, the exact same things happen to my 170 inch flathead.
            Coil nope, not the problem
            fuel, not a problem (filter, pump)
            replaced the distr. condensor...problem gone.

            Mike

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            • #7
              Kinda sounds like the ethanol gremlin has struck again.

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              • #8
                About 50 or so years ago, I read a Tom McCahill book and it stated that, in trouble shooting running issues, that 90% of the time it will be ignition related, and only 10% of the time will it be fuel related. I must say, in all the years of my fooling with Studebakers, that those percentages are pretty close to correct. So I always start with the ignition components.

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                • #9
                  If you're gonna drain the tank " I'd go as far as dropping it and cleaning it out completely" BTDT.
                  Originally posted by sactorandy View Post
                  Jack, I have a new filter between the tank and electric pump and between the mechanical pump and the carb. The car sat for 18 years before I got it and has been running for about 3,000 miles. I did not drain the tank before I got it running but it has been running fine. I will drain the tank and change the front filter since the other one is only a month old. I think the water diagnosis is probably correct. What else could it be? Randy
                  Joseph R. Zeiger

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                  • #10
                    Originally posted by 63t-cab View Post
                    If you're gonna drain the tank " I'd go as far as dropping it and cleaning it out completely" BTDT.
                    I agree with Joe. After getting stuck with my '54 4-door soon after getting it, I found that there was 'trash' (actually red RTV that some past owner or so-called mechanic had glopped under the fuel level sender) floating around in the tank. It would get sucked up against the pickup, and the car would start running terrible and then quit. After a while it would start again, and repeat the cycle all over again. The gas tank from my Snapper riding mower tied under the hood with bungie cords got me home. Used a couple of coffe cans full of nuts and bolts inside the tank and a couple of gallons of MEK (only do this outside, kids!) and a couple of hours of sloshing around and the tank came out really clean. No problems since.
                    Paul
                    Winston-Salem, NC
                    Visit The Studebaker Skytop Registry website at: www.studebakerskytop.com

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                    • #11
                      The easiest place to start looking is to pull the plugs and check them. Replacing the points and condenser is easy too and relatively cheap. Also check the coil as suggested.
                      Sometimes a little piece of junk will start roving around in the carb bowl and intermitently plug jets. One way to test this is: if you are driving and it starts to miss can you pump the gas to get it to run better momentarily? If yes, open and clean the carb out. Sometimes you can clear it up by removing the mixture screw and blowing compressed air into the carb hole to dislodge the culprit. If this works the particle is still in the carb and must be removed or it will happen again. I also think replacing the filters is also a first priority. It would be nice to find the problem by eliminating symptoms before tearing everything out and replacing stuff.
                      rob

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                      • #12
                        I try to aim before firing the shotgun.
                        Pretty early on I'd check for blue spark when cranking with new plug with widened gap.
                        Among the first things I'd do is disconnect fuel line near the carb, ground the coil wire, and crank the engine to squirt an inch or 2 of gas into a clean glass jar or pyrex measuring cup.
                        The purpose is to visually inspect the gasoline being fed to the carb. It should be crystal clear, and clean. A blob rolling around the bottom of the jar is even more serious. Even if I think it's OK I usually splash in some isopropyl drygas. If after the swirling stops it is noticeably clearer there was some water dispersed in the gas. I'll add 1 or 2 bottles of drygas to gasahol even though it is raising the alcohol content

                        A cup of Massachusetts 10% ethanol will become murky if left out on a humid day. I believe that it is pulling the moisture right out of the air. The surface to volume ratio is lower/better when the gas is in the tank, but the process of water absorption is still going on.

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                        • #13
                          I agree with the 90%-electrical rule. I had a similar problem with my '59 Silver Hawk with the 170. I got a great deal on the car because despite a complete and very pretty restoration the previous owner couldn't get it to run right. None of the standard tune-up procedures had any effect. Eventually I figured out that the resistance wire for the ignition system had lost its resistance. I replaced it with a ceramic resistor and she ran like a top.

                          Steven Ayres, Prescott AZ
                          58H-K7 660

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                          • #14
                            This sounds like something I should do. Is the resistance wire for the ignition the wire from the distributor to the coil? Do I just run a new wire from the distributor to a resistor and from the resistor to the coil? What gauge wire and what ceramic resistor? Are ceramic resistors all the same?

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                            • #15
                              A condensor is cheap and easy to replace..!

                              Mike

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