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Technical 3 deuces on SBC running out of gas??

Discussion in 'Traditional Hot Rods' started by 49Dodgeboy, Aug 5, 2024.

  1. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    Thanks. The lines are all 5/16 and new. I followed the factory bends from tank to engine. But I did put a pretty good bend in it between pump and filter. I will review that. I am doing my best to stay period correct but looks always get in the way
    IMG_2572.jpeg
     
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  2. That bend isn't your problem, it's got a much better radius than that 90* fitting going into the filter.
     
  3. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    here's some thing for you to read,... not saying it will work... as I don't even know how to put shocks on.... but the first thing I would do is unhook the fuel line at the fuel block... put that linein a 5 gallon jug and turn on the pump...see what happens...... if that passes....un hook the line to a carb and do the same... I've never had to put a fuel pressure reg. on each carb???? maybe the pump doesn't put out enough pressure for 3 regs.
     
  4. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    just a comment here, but, with an electric pump couldn't you check with the car sitting???
     
  5. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    There is only 1 regulator, just before the fuel log.
     
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  6. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    ya, works fine sitting still, will pump pressure up to 5#'s if I would let it...
     
  7. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    ok, got cha... so even more easy... un hook past the reg and put a fuel pressure gauge.... see what it reads.... next... unhook gauge and pump fuel into a gas can w/ reg on... go 3 or 4 gals and see what it does... if it starts drizzling, do it over with the reg off.... if it starts to drizzel again... go to the pump and check for loose fitting... loose will suck air and not leak...
     
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  8. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    what about volume??? one thing i ran in to, some one got way over zealous with the teflon tape and it was wadded up in the fuel block and carb intakes...if you have pressure and volume... the problem is forward of the reg,... another time it was the fuel inlet valve going into the carb was too small.. worked great untill you needed full fuel suply... changed out the inlet valves to bigger and it quit,... again, just something to check... I know zero about cars...
     
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  9. HOTRODNORSKIE
    Joined: Nov 29, 2011
    Posts: 478

    HOTRODNORSKIE
    ALLIANCE MEMBER

    I'm spit balling here but it sounds like a classic vapor lock like your gas is boiling getting to hot had that problem with my 292 YBLOCK put a spacer under my holley that fixed it. You may have a chunk of shit in that center carb shift into 3 it falls on its face but it doesn't explain feathering it home after that love to hear from some of the tech guys on this one good luck.
     
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  10. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    I am going to start at the tank and remove the lines and check all the fittings. Never thought about the size of the inlet..... I appreciate throwing things at me....
     
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  11. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    hmmmmmmmmm that manifold gets hotter than hell too......... lots to look into
     
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  12. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    if you have volume and pressure past the reg... bet problem is fuel block to carbs..
     
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  13. 6sally6
    Joined: Feb 16, 2014
    Posts: 2,639

    6sally6
    Member

    My (M-word) doesn't have 3 twos but....my 600 cfm Eddy carb started doing the same thing .
    Wring-it-out in first...second...1/2 way through third it would fall on its horse-face ! Spit and sputter like it was outta fuel....plugged up filter.
    Ended up the battery was getting weak !!! Replaced the battery and problem solved !! Must have been effecting the MSD ignition box !??!
    ( I do have one of those little glass fuel filters everybody sez is a fire hazzard and when it starts to get dirty it spits & pops too)
    Howz your battery ?
    6sally6
     
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  14. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    Well, the battery is only maybe a year and a half old, charging system works too. I will look at amp gauge next time it happens. I guess a week coil could do the same ?? I know its old
     
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  15. lostone
    Joined: Oct 13, 2013
    Posts: 3,185

    lostone
    Member
    from kansas

    I had a car that would, sitting still, Rev to the moon, but under load it would only pull about 3500 then cut out then it wouldn't pull itself up a hill. Coast down the hill kick it in neutral and Rev no problem. But in gear stumble under load, it was the filter in the gas tank.....

    ...
     
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  16. 05snopro440
    Joined: Mar 15, 2011
    Posts: 2,049

    05snopro440
    Member

    Mine would do something similar. Fine at idle, but under load it would stumble and fall on its face. A rubber pickup line in the tank was collapsing.
     
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  17. lostone
    Joined: Oct 13, 2013
    Posts: 3,185

    lostone
    Member
    from kansas

    @05snopro440 yep its funny how a load changes everything. Luckily I had a buddy that went thru it before me and he found it by using a fuel pressure gauge tapped to the hood.

    Said it held a constant 7 psi in the shop revving it, holding it at 4000 rpm etc. But under load it could watch the pressure gauge slowly drop even before he could feel it in the rpms. That's how he figured out something was plugging or collapsing as he drove it. With the pressure dropping slowly he knew something just wasn't shutting off.

    ..
     
  18. While fuel pressure is somewhat important, possibly even more so is fuel volume. Pressure does not automatically equate to volume. This has already been alluded to in a few previous posts.

    While you've got the fuel plumbing apart would be the perfect time to check the fuel pump volume. I don't know what the specs call for but they're probably listed somewhere on Holley's website.
     
  19. Tow Truck Tom
    Joined: Jul 3, 2018
    Posts: 2,554

    Tow Truck Tom
    Member
    from Clayton DE

    Just a shout-out to Gypsy Green
    :D
     
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  20. X-cpe
    Joined: Mar 9, 2018
    Posts: 2,084

    X-cpe

    When you start at the tank, check inside for trash. My first thought was a loose piece of trash being sucked over the outlet under higher flow conditions, then dropping off on shut down.
     
  21. 05snopro440
    Joined: Mar 15, 2011
    Posts: 2,049

    05snopro440
    Member

    If you're not getting enough fuel volume, you will see it in your fuel pressure. You check pressure as an indication of fuel starvation.
     
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  22. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    Well, it was a running car with a flat head six & a 5 speed that had no problems with the tank before I tore it down to do the transformation. BUT that was 2 yrs ago now so it's on the list.
    before shot as a Kustom: 49-1.jpg
     
  23. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    spot on post... volume is what you need to not run out, pressure is what blows the inlet valve and over fill the bowl,.. had a guy argue this years ago... I took a c clamp and put it on the rubber hose , the more I turned it the less volume and finally nothing... so,... like I said.... first thing to do would be un hook with the reg on and pump into a gas jug and see how long it takes to pump 3 gals. and see if the volume drops... if thats fine you know it's forward.... I always start there cause it's the easiest
     
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  24. ALLDONE
    Joined: May 16, 2023
    Posts: 1,579

    ALLDONE
    Member

    you just have to remember the basics... once the fuel is in the carb, there is no pressure....and with out the volume replacement... you run out.....
     
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  25. el Scotto
    Joined: Mar 3, 2004
    Posts: 4,720

    el Scotto
    Member
    from Tracy, CA

    Those Hurst mounts originally came with spacers to move the mount out away from the front of the engine. I used one in a '48 Mercury with a 283 and with spacers was able to use a stock Carter 'Corvette' style fuel pump.

    This is more of an FYI in case you feel like redoing it at some point. Good luck getting the actual problem addressed!
     
  26. I looked at your picture of the pump and filter canister and wasn't able to tell if the filter was going into the pump inlet. If that is the case then you don't want the filter element to be too fine before the pump, only 100 microns, then a finer filter after it. If the pre filter is too fine then the pump will struggle to draw fuel through it.

    This also sounds like an ignition coil starting to fail, stalls, starts again after sitting and revs great under no load.
     
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  27. mustangsix
    Joined: Mar 7, 2005
    Posts: 1,444

    mustangsix
    Member

    We had a similar setup with similar symptoms some time ago. Three deuces, progressive linkage . It would idle fine, run ok until you nailed the throttle, then fall flat and quit. Started up again no problem.
    We found that one of the outer carbs had a stuck float and there was no fuel in the bowl. Hitting the throttle would open that carb and lots of air, no fuel, engine died.
     
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  28. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    THX for the info. Most guys that do a SBC into an early Mopar install the mounts that move the engine 1 " away from the steering box. Me trying to be the 60's period correct guy I wanted a "driveway" install so in centered but mounted higher and forward of most guys. Even with the spacers it would still hit the frame.
    Appreciate you taking the time to look and give me input.
     
  29. 49Dodgeboy
    Joined: Aug 17, 2006
    Posts: 713

    49Dodgeboy
    Member

    The old Fram style filter is installed after the pump, none before it (yet) :)
    I agree with the coil, its an old one that I had. Doing fuel volume test first then going straight to the coil....
    Appreciate the input very much. Rich
     
    Pocket Nick likes this.
  30. el Scotto
    Joined: Mar 3, 2004
    Posts: 4,720

    el Scotto
    Member
    from Tracy, CA

    Know all about that steering box issue. We did a slant six 3 speed into a '50 Dodge Coronet and had to offset the engine to the passenger side just like you said.
     
    49Dodgeboy likes this.

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