70 V code takes time to start after a few days

A12 Mopar Discussions

  1. biomedtechguy

    biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

    Messages:
    25,363
    Likes Received:
    36847
    Joined:
    Mar 28, 2014
    Location:
    South Louisiana
    Local Time:
    9:51 AM
    Happy New Year to my 6 bbl cousins!
    After my 6 bbl 440 has not been run for a week or more, it takes a lot of time cranking it over to get fuel into the carbs-at least that is how it behaves. This has always been the case since I bought it 3 years ago. Once it gets fuel, everything is fine.
    I bought the stock pressure high volume Carter fuel pump that is so popular amongst the 6 bbl crowd, BUT I haven't installed it yet, but I am definitely going to, along with a new in line fuel filter.
    Since the motor runs well at all speeds and starts fine once the carbs (bowls?) fill with fuel, is it "normal" to lose the fuel after a week or more of sitting up? Could it be another issue? Might the new fuel pump fix the problem?
    Thanks
     
  2. thomas patti

    thomas patti Well-Known Member

    Messages:
    289
    Likes Received:
    30
    Joined:
    Mar 11, 2012
    Location:
    texas
    Local Time:
    8:51 AM
     
  3. thomas patti

    thomas patti Well-Known Member

    Messages:
    289
    Likes Received:
    30
    Joined:
    Mar 11, 2012
    Location:
    texas
    Local Time:
    8:51 AM
    hay,patti. have a A-12 road runner w/the same problem,just living w/it. also have a hemi GTX w a 528 ray barton in . put a 120 gal electric pump on it and no problem,thx
     
  4. 67GTX440

    67GTX440 Well-Known Member

    Messages:
    1,014
    Likes Received:
    425
    Joined:
    Nov 29, 2012
    Location:
    Jacksonville, FL
    Local Time:
    10:51 AM
    My 67 GTX is the same. I have an auxiliary electric fuel pump on a switch on the dash in addition to the mechanical fuel pump. If car has been sitting, I let the electric fuel pump run for about 15 seconds and then pump the gas pedal four times and the car starts instantly without ever seeming to crank. Without doing this the car cranks for 60 seconds or more which causes stupid wear on a lot of things.
    The fuel runs back to the tank when the car sits. Just cranking it until the mechanical fuel pump draws fuel to the carbs is not good. These cars were not designed to sit without being started and driven.

    The automatic transmissions give another whole set of issues after sitting for a while. This is why cars regularly driven may not leak transmission fluid and those infrequently driven leave transmission fluid spots on the garage floor. Sitting causes drain back of transmission fluid from torque converter to transmission pan causing minute dipstick filler overflow. This is the reason automatics need to be allowed to idle for 30 seconds in gear before driving if they have been sitting a while.
     
    • Thanks! Thanks! x 2
    • biomedtechguy

      biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

      Messages:
      25,363
      Likes Received:
      36847
      Joined:
      Mar 28, 2014
      Location:
      South Louisiana
      Local Time:
      9:51 AM
      Thanks guys. I have considered adding an in line electric pump for start up only, but I don't want it to interfere with or alter the fuel flow during normal operation. Would an in line pump when it is off have any effect on fuel flow?
      I have a 4 speed, so the auto transmission issue is one problem that I don't have, but that is good info.
       
    • 67GTX440

      67GTX440 Well-Known Member

      Messages:
      1,014
      Likes Received:
      425
      Joined:
      Nov 29, 2012
      Location:
      Jacksonville, FL
      Local Time:
      10:51 AM
      Mine is off during normal driving. Fuel flow after sitting start is from mechanical fuel pump only. Fuel flows freely through electric fuel pump when off. Prime's carb only.
       
      • Thanks! Thanks! x 1
      • Agree Agree x 1
      • biomedtechguy

        biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

        Messages:
        25,363
        Likes Received:
        36847
        Joined:
        Mar 28, 2014
        Location:
        South Louisiana
        Local Time:
        9:51 AM
        Man that's great! So is it inline? What brand and model# please? Where is it located?
         
      • 67GTX440

        67GTX440 Well-Known Member

        Messages:
        1,014
        Likes Received:
        425
        Joined:
        Nov 29, 2012
        Location:
        Jacksonville, FL
        Local Time:
        10:51 AM
        It is inline in the fuel line and is screwed into the underside of the raised forward portion of the trunk on the right hand underside. It is grounded to the body and has a hot wire run to a switch under the dash. I don't know the brand as it was there when I bought the car. Inline in a rubber hose off the gas tank. It is a really small and cheap and noisy pump. You can tell when you have fuel pressure since it is quite noisy when it siphons and quiets down when full fuel flow is achieved. You can still hear it if on, so there is no worry about leaving it on. It probably works better the closer it is to the fuel tank where it has to pull (siphon) less gas before the pump is full. Any 12 volt fuel pump should work as long as outlets fit the fuel line and it free flows when not running.

        I would just check the Summit Catalog or local auto parts store. This is a common old carburetored car staple. Does not need much fuel flow since only priming. Maybe someone who has added one more recently can give a brand and model. Every common parts supplier seems to make one such as Airtex.

        This one from Summit is cheap and has all the required fittings except a dash switch and a longer hot wire to the switch. My hot wire runs under the car with the fuel line and through the speedometer cable hole in the firewall to the dash switch and from the switch to a switched hot (hot when ignition on only) in fuse box. Ground is grounded to body by the pump. You can spend a lot more, but this is all it takes.

        https://www.summitracing.com/parts/atx-e8012s/reviews/

        Lots of reviews at this link.
         
        Last edited: Jan 1, 2017
        • Thanks! Thanks! x 1
        • biomedtechguy

          biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

          Messages:
          25,363
          Likes Received:
          36847
          Joined:
          Mar 28, 2014
          Location:
          South Louisiana
          Local Time:
          9:51 AM
          Thanks!!!
           
        • PurpleBeeper

          PurpleBeeper Well-Known Member

          Messages:
          4,718
          Likes Received:
          3454
          Joined:
          Mar 20, 2011
          Location:
          Chicago
          Local Time:
          9:51 AM
          I run a Holley blue electric pump only (no mechanical). The fuel in my center carb definitely evaporates. I would have the same issue except I start my fuel pump about 15 sec. before cranking the motor once the fuel pressure is up (gage on hood)
           
          • Thanks! Thanks! x 1
          • Agree Agree x 1
          • 440+6

            440+6 FBBO Gold Member FBBO Gold Member

            Messages:
            3,482
            Likes Received:
            3194
            Joined:
            Oct 2, 2012
            Location:
            Farmington, Michigan
            Local Time:
            10:51 AM
            Do you have a choke? Set properly?
            Mine starts almost instantly no matter how long it sits when cold.
            When hot (within an hour of shutdown) it takes about five seconds or more to fire up.
            I'm using the Carter mechanical pump only.
             
          • biomedtechguy

            biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

            Messages:
            25,363
            Likes Received:
            36847
            Joined:
            Mar 28, 2014
            Location:
            South Louisiana
            Local Time:
            9:51 AM
            I have an automatic choke, it works fine. The problem is that I don't have any fuel in the carbs after it sits for over a week, and I have to crank it for 40 seconds or so to overcome that. Once fuel is present, everything is good.
             
          • 440+6

            440+6 FBBO Gold Member FBBO Gold Member

            Messages:
            3,482
            Likes Received:
            3194
            Joined:
            Oct 2, 2012
            Location:
            Farmington, Michigan
            Local Time:
            10:51 AM
            The only things I have done are 1\4 inch phenolic spacers (would go thicker but I have an air grabber) and insulated my fuel lines from the pump to carbs, also insulated both lines from tank to rocker.
            I did the above for my hot starting problem, never had a problem with cold starting no matter how long it sits, even a month or two.
            I use a 195 deg thermostat and my heat crossovers at wide open and don't boil fuel out of the carb.
            Wish I had an answer for you, seems like allot of fuel to evaporate.
             
            • Thanks! Thanks! x 1
            • moes

              moes Well-Known Member

              Messages:
              896
              Likes Received:
              1247
              Joined:
              Dec 18, 2015
              Location:
              CANADA
              Local Time:
              10:51 AM
              hard starting after sitting is a common problem with 6 pack cars. I tried everything to fix it, I had no luck. I had the carbs rebuilt and still the problem was there. Most guys (like me) just live with it or as other guys have said using a electric fuel pump will fix the problem, turn the key and you have gas immediately to the carbs and it starts.
               
              Last edited: Jan 5, 2017
              • Thanks! Thanks! x 1
              • biomedtechguy

                biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

                Messages:
                25,363
                Likes Received:
                36847
                Joined:
                Mar 28, 2014
                Location:
                South Louisiana
                Local Time:
                9:51 AM
                Thanks. I am going to install the high flow/stock pressure Carter mechanical pump first, and then if still needed, I am going to source an electronic fuel pump just to push fuel into the carbs for this issue, and that free-flows when off, making sure that it won't restrict the flow when off.
                Great replies and information, I appreciate all who replied. Thanks. I will follow-up in this thread for future archival purposes.
                 
              • Frustration

                Frustration Well-Known Member

                Messages:
                501
                Likes Received:
                689
                Joined:
                Dec 8, 2014
                Location:
                PA
                Local Time:
                10:51 AM
                Mine runs similar to the ones mentioned above. I have a Carter electric pump in the rear, flowing through a Carter mechanical and 3/8" lines. In the warm weather, it's not a problem. In the colder weather (I live in PA so the range it gets driven is 30-90 degrees outside) it is. My warm weather routine is two pumps to the floor (with the gas pedal), then crank for a few seconds. It usually starts. If not, I give another pump, and it will definitely start.

                In the cold weather, I start the electric pump to prime the bowls. I then pump three times and crank for a couple of seconds. Then repeat. I may end up giving 6-8 total pumps of the pedal before it starts.

                The key to knowing is by only cranking for a few seconds. When it finally kicks, but doesn't start, the next pump will do it. That being said, I always need to feather the pedal for the first couple of minutes of warm up. I do not have a choke, and use the 500CFM center carb. (It's being discussed now in the Racers Forum). Good luck.
                 
              • 62MAX

                62MAX Well-Known Member

                Messages:
                1,573
                Likes Received:
                1106
                Joined:
                Jul 21, 2008
                Location:
                PA
                Local Time:
                10:51 AM
                I'll make a minor adjustment to your first sentence,hard starting after sitting is a common problem with "SOME" 6 pack cars.Finished this 4 spd in 1992,Carter 8 psi Hemi pump,101 AV gas,choke set the way it is supposed to be,can sit a week,month or longer and will start in no more than 5 revs and you can drive it away.

                77304-8.jpg
                 
                • Like Like x 1
                • flypaper

                  flypaper Well-Known Member

                  Messages:
                  16,870
                  Likes Received:
                  26925
                  Joined:
                  Jul 17, 2008
                  Local Time:
                  10:51 AM
                  I'm surprised nobody has yet mentioned
                  double check all of your fuel lines and connections all the way back to the tank.
                  that has fixed many a hard starting vehicle for me..
                   
                • Dragon Slayer

                  Dragon Slayer Well-Known Member

                  Messages:
                  465
                  Likes Received:
                  198
                  Joined:
                  Jun 18, 2014
                  Location:
                  Virginia
                  Local Time:
                  10:51 AM
                  Just working through this with a hemi car. Fuel pump was bad, and would not prime carbs when just cranking. Once primed and started and warm would start on first rotation. Pump fixed that. But still have issue with back carb pumping fuel. Most likely accelerator pump seal gone bad (sitting dry too long). So still a little cranky starting cold with just front carb pumping fuel. So you need to check complete system.

                  Now a 383 Carter 4 bar can sit and I can crank for about 6 sec. Pump and start right up even if sitting a month. Carb has been adjusted, but probably not rebuilt in about 20 years and looks it! But car runs great so not going to touch it.
                   
                  • Thanks! Thanks! x 1
                  • biomedtechguy

                    biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

                    Messages:
                    25,363
                    Likes Received:
                    36847
                    Joined:
                    Mar 28, 2014
                    Location:
                    South Louisiana
                    Local Time:
                    9:51 AM
                    I still haven't replaced the fuel pump even though I have had the replacement Carter for months. I will report back once I install the new Carter mech fuel pump.
                     
                  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
                    By continuing to use this site, you are consenting to our use of cookies.