Priming/starting help

Discussion in 'PSI Superchargers Tech Questions' started by CjRedden, Jul 30, 2012.

  1. CjRedden

    CjRedden Member

    Joined:
    Jan 16, 2010
    Messages:
    153
    Likes Received:
    0
    So im pretty new to this whole fuel injection system. 526 cu in chevy, dart block pr1 heads. littlefield 8-71 with a carbon hat. Everything was set up for me when i installed the motor. My problem is getting this thing started. 24 volt block starter with a promag44. the car runs great once it starts. idles about 1800. our problem is most of the time it takes alot of cranking and alot of gas to prime this thing before it fires and stays running. usually fires on the gas then dies right away sometimes 2 or 3 times as my dad is trying to prime it th rough the butterflies. im curious to know exactly how to reset the butterflies from my understanding you need a .010 gap. where do you check this. From what i see, the gas doesnt get sucked into the motor through the bottom of the butterflies as it puddles up and drips down the front of the blower. any suggestions or help?
     
    #1
  2. Vhodoo Racing

    Vhodoo Racing New Member

    Joined:
    Jan 5, 2011
    Messages:
    99
    Likes Received:
    0
    I have a 526 Chev with a 14-71... We prime with plastic bottle (mustard bottle work well) and methanol. When we first got this engine going we were having a similar problem which boiled down to just giving it a good drink to get it fired and then running on the bottle until the fuel pump well and truly picks up and takes over, it can take quite a few seconds... We simply were not running it on the bottle long enough for the fuel pump to take over...

    Cheers
     
    #2
  3. vht

    vht Member

    Joined:
    Sep 14, 2011
    Messages:
    38
    Likes Received:
    1
    What about a priming system that uses a small elec fuel pump?
     
    #3
  4. fastfiat

    fastfiat New Member

    Joined:
    Oct 21, 2009
    Messages:
    50
    Likes Received:
    0
    Had a similar problem with our car. Finally drilled out the opening on the prime bottle (3/32)and that fixed it. Takes more fuel than you think but you can flood it if not careful.
     
    #4
  5. CjRedden

    CjRedden Member

    Joined:
    Jan 16, 2010
    Messages:
    153
    Likes Received:
    0
    we prime it with gas. but for the most part having it fire on the original squirt is no problem, but keeping it running on the gas seems to be the issue. dribbling the gas onto the bottom of the butterfly doesnt seem to be pulling in the gas as if the bottom of the butterfly is dragging on the carbon fiber. i talked to the builder and he recommend i back off the idle screws loosen the screws on the butterflys, close it all the way and that should re center them as if they may have fallen down just enough to be causing problems. making the opening in the bottle bigger didnt seem to help since when we had done that, the gas would just puddle up and fall down onto the belt rather than pull into the motor
     
    #5
  6. buzillamini

    buzillamini Member

    Joined:
    Sep 20, 2009
    Messages:
    45
    Likes Received:
    1
    Here is how we do it. Turn fuel on crank untill you see oil pressure then open butterflys all the way open. Person who has been priming for you can then look into the injector to see fuel coming out of the nozzles when they see it they motion to you. You then close the throttle and hit the mag switch. Fires every time and keeps running. We never use a primer bottle. And have never flooded it this way. I also would not mess with the butterflys if you are not having any problems with them sticking or with the idle.
    Good luck.
     
    #6
  7. Stephen McClain

    Stephen McClain New Member

    Joined:
    Nov 14, 2006
    Messages:
    40
    Likes Received:
    1
    We did our alcohol car the same way and it did work just like you said. One thing you need to be sure of is that the mag is off when you do that !!!!!!
     
    #7
  8. thesleddawg.com

    thesleddawg.com New Member

    Joined:
    Sep 29, 2011
    Messages:
    11
    Likes Received:
    1
    This is what I do, and it works well.

    This is certainly looked upon as unusual with a few cocked heads. I open the butterflies and spray 5 seconds worth of FLAMMABLE brake clean, close the butterflies, start the engine and continue to spray the brake clean until it run smoothly. There are 2 different brake cleans, flammable, and non-flammable....... the guy I learned this from has been to this for well over 25 years, and I have been doing it now for a few years. Brake clean (flammable) isn't as powerful as starting fluid, and will don't damage engine components if you use too much. Because it has a long shooting distance, it is safer and you can stand farther back from the moving parts.

    hope this helps
    sean
     
    #8
  9. jay70cuda

    jay70cuda Well-Known Member

    Joined:
    Sep 30, 2009
    Messages:
    1,139
    Likes Received:
    35
    I'm assumming your starting it with 24 volts and not 12 ? And why gas. Meth works just fine. What is the plug gap. .015-.018. It sounds like you don't have enough fuel psi while it's running. Our Chevy had over 100 psi at idle. Don't worry about the blades , set them where it wants to be at. .013 at the bottom of the blades is a good start. Where is the barrel valve at when idling 1.0 gallon ? Keeping the blades too far closed will make it hard to start as well. Hope this helps
     
    #9
  10. tc1216

    tc1216 Member

    Joined:
    Dec 13, 2005
    Messages:
    98
    Likes Received:
    1
    if you have a data recorder, run it while you are trying to start it. I will bet it is not spinning fast enough. A mag 44 needs a minimum of 250 rpm to fire.
    i have seen this same problem several times before.
    hope this helps,
    tom
     
    #10
  11. Randy G.

    Randy G. Top Alcohol

    Joined:
    Jun 9, 2003
    Messages:
    1,902
    Likes Received:
    36
    Gas burns fast and it's gone. Alky is harder to light when cold then burns slower. I mix alky and gas in the squirt bottle 50/50. Works (almost) every time and it's easy to start.
     
    #11
  12. Moparious Maximus

    Joined:
    Feb 23, 2009
    Messages:
    401
    Likes Received:
    2
    We use gas because it lights so easy but yes, its a little tricky to get it right but once you get it figured out it works great. You need someone who understands these engines to be your primer guy. Too many times I've seen motors drowned in the lanes or under-primed and die...many times. I've had it happen to me, when we were learning and had free and very inexperienced help, its really frustrating to have starting problems...
     
    #12
  13. Bill Naves

    Bill Naves Member

    Joined:
    Jun 25, 2003
    Messages:
    594
    Likes Received:
    0
    alcohol is best above 70 degrees

    we find alcohol is the best primer above 70 degrees..colder requires some gasoline or it will not fire,,,


    you might want to watch this before using brake clean.. www.youtube.com/watch?v=VmtkUxvACcY
     
    #13
  14. Ken Sitko

    Ken Sitko Super Comp

    Joined:
    Oct 21, 2003
    Messages:
    759
    Likes Received:
    0
    Please DO NOT spin the motor with the butterflies open to watch for the fuel to come out of the nozzles. I have raced against a few people that had the car fire, and ran over their whole crew. All it takes is for your ground wires to fall off, or mag switch mistakenly left on.

    That said, our starting procedure is:

    Open butterflies
    Squirt liberal amount of 50/50 gas/methanol mixture in (at least 2 seconds worth)
    Close butterflies
    Spin motor, spray steady stream into bottom of butterfly as car is starting
    Continue until motor is running on its own.

    Pure methanol will work if motor is already warm, or outside temp is 70 degrees or more

    Pure gas is a bad idea, very easy to flood.
     
    #14
  15. Comax Racing

    Comax Racing Member

    Joined:
    Sep 20, 2006
    Messages:
    673
    Likes Received:
    7
    Interesting about the 50/50 mix. I have always just used straight gas, I will give that a try. Great tip.
     
    #15
  16. moldenhauerracing

    moldenhauerracing New Member

    Joined:
    Jul 31, 2011
    Messages:
    171
    Likes Received:
    0
    With butterflies open ? Did you see what happened to the crewman on the Greeks car on start up?
     
    #16
  17. aort

    aort Member

    Joined:
    Sep 26, 2010
    Messages:
    55
    Likes Received:
    0
    I hold my butterflies about 1/4 open until I can see fuel out of the pipes and then close them. The tone changes just a little when that happens also. Flip the mag on and it starts right up. This is also on a twd truck, so it has a neutral safety start on it.
     
    #17
  18. Mike Evans

    Mike Evans New Member

    Joined:
    Jun 12, 2008
    Messages:
    27
    Likes Received:
    0
    start up

    a switch on the blower solves that. who would ever rely on a driver?
     
    #18
  19. promodracer

    promodracer Member

    Joined:
    Jan 8, 2008
    Messages:
    359
    Likes Received:
    2
    I like this!
     
    #19
  20. xXx

    xXx TAD Temp guy

    Joined:
    Apr 2, 2005
    Messages:
    81
    Likes Received:
    0
    Starting procedure

    I agree with Ken, this is the same process we use and is seemingly hassle free.
     
    #20

Share This Page