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Drug home another project today... 61 unibody shortbox

Discussion in 'The Hokey Ass Message Board' started by Gearhead Graphics, Aug 9, 2010.

  1. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Been thinking I needed another project, so I decided a unibody would make a good "shop truck" for my pinstriping gigs.

    61 swb unibody. A couple owners back someone swapped in a 351 and a C6 trans (cool, but I wish it had a Y block)

    I'll put a pic here, a few more in my profile folder.

    I'm not much of a motor guy so I'll throw this out and ask for advice. Last owner put on a new carb (Edelbrock750ish cfm) and now if you rev it under no load it revs fine, but if its under load it coughs and sputters like mad if you get after it very much more than grandma would. He thinks its the carb, I question if its not something like timing or vacuum advance type stuff.
    I'm really more of a paint an body kinda guy, so I welcome any suggestions to tracking down this culprit.

    [​IMG]


    Sloppy steering is first on the repair list after this running issue, then rust repair on the cab mounts and drivers footwell. Otherwise It's pretty free of too much rot.
     
  2. captainjunk#2
    Joined: Mar 13, 2008
    Posts: 4,420

    captainjunk#2
    Member

    looks pretty sharp , all it needs is a good dog to ride along in the p***enger seat
     
  3. LM14
    Joined: Dec 18, 2009
    Posts: 1,936

    LM14
    Member Emeritus
    from Iowa

    Welcome to the world of Slicks. Might want to lok here for a lot of info.

    http://fordtruk.com/forums/

    For your miss problem, check plugs and fuel filter first. Look at the easy stuff.

    Here's mine!

    SPark
     

    Attached Files:

  4. hemiboy
    Joined: Apr 21, 2005
    Posts: 249

    hemiboy
    Member

    First: swap out the carb for a known good 600 cfm Holley or Edelbrock. You don't even have to hook up throttle linkage. If that cures it, you're good! If not, then find someone who can help you and start with the basics- timing, point gap (if applicable), fuel pump pressure, plugs, cap, rotor, wires. A 750 sounds like it's way too big for the engine- must be drowning it. I'm running a 600 model 1850 on the 351 in my Mustang and it's plenty. As for steering, think Volare front suspension. Cheap, heavy duty and easy to install.
     
  5. Ghost28
    Joined: Nov 23, 2008
    Posts: 3,192

    Ghost28
    Member

    Wow you didnt say it was that nice. Great looking truck. I will give ya a call on that chevy crank sometime this week...John
     
  6. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    It looks really nice from a half block away. its got some issues up close, but really solid for what it is and the price.

    It's got an electric fuel pump (need to do a block off and get rid of the manual thats left behind) and it has electronic ignition, so no more pints (hoorah!)

    Tomorrow its getting the major pressure wash job and I'll start in on checking things out. running a fram filter on it now and I just cant let that stay (personal issues). Plugs and such will be checked and as i can the spaghetti wiring will disappear.

    In the next week or so I hope to have my stripe logo on the doors and have it running like it should. As is in the rain its like a cat on gl*** for traction, running right its gonna be fun!

    John. I'm off until Friday, so anytime is fine
     
  7. Other than checking timing, and regular tune items, fuel pressure is critical with Edelbrock carbs. Try to get to 4-4.5 psi.
     
  8. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Swapping on a 600 won't tel anything unless it's driven as it runs fine under no load. I'll see if I can figure fuel pressure and maybe get a regulator on it.
    Double checked with po to see what the cfm is on it.
    Will be pulling plugs and giving it a once over this afternoon.
     
  9. ken bogren
    Joined: Jul 6, 2010
    Posts: 1,057

    ken bogren
    Member

    One of my favorite style of pickup trucks.

    I think that "Cat on Gl***" traction was a special order option, if I recall right. :)

    My 61 uni seems to have it also, thanks to whoever installed the 460 in it.
     
  10. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    460? yeah, thats a cat on gl*** setup for sure.

    Just heading out to the garage for the day. Complete cleaning and see if I can't start in on that running issue... pulling plugs and such to get some more ideas. Found a couple smaller CFM carbs on craigslist that i might try out on it if plugs read rich.
     
  11. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    p.s. if any of ya Denver guys wanna come show me how little I know about motors I've always got plenty of cold drinks in the fridge,, and a wet pinstripe brush...
     
  12. theHIGHLANDER
    Joined: Jun 3, 2005
    Posts: 10,772

    theHIGHLANDER
    Member

    Steering...Turn the wheel one way or the other almost to "lock". Loosen the gear adjuster locknut and run it down to where it stops and back off just enough for clearence. Run it back to center and check play. Should be really close if not perfect. Now a disclaimer here, that's ***uming the tie rod ends and kingpins are all good as well as the pitman arm. Early Ford pickem ups are known for the adjuster wearing down, left alone too long it will wear the worm gear pretty bad and won't be fixable w/out a total box rebuild.
     
  13. G V Gordon
    Joined: Oct 29, 2002
    Posts: 5,724

    G V Gordon
    Member
    from Enid OK

    I am thinking a 750 is too big for a mild/stock 351. You may just be overcarbed. As suggested, switch it out for a smaller carb and see if that fixes it.

    The bigger is better school of thought has got a lot of people in trouble.
     
    Last edited: Aug 10, 2010
  14. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Plugs are a pretty OK looking dark tan. not fouled out. Inside of air cleaner is obvious that its been backfiring out the carb....

    I'm on the hunt for a smaller carb as well...
     
  15. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Thanks for advise on steering. The rods and links feel firm. Though I can also feel in it and the tires tell me it needs aligned too.

    Po now tells me he can't remember size of carb. Is there a casting mark or stamp on it that will give it away?

    Cleaned it up a lot today and did a flushing clean on the carb. It runs a bit better but the cough is still there.
     
  16. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Checkednour the carb today via edelbrock website. It's a 600cfm model. So that throws a new kink in the mix. All plugs yesterday were nice and tan but it smells like unburbed gas when running.
    Next suggestion?
     
  17. TexasDart
    Joined: Oct 11, 2007
    Posts: 853

    TexasDart
    Member

    Check your timing....and also check for vacuum leaks....if the plugs aren't wet looking then it doesn't sound rich. You might check the mixture screws. Turn them in and then back them out 1.5 turns...that should be a good starting point.
     
  18. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Sat screws back to stock settings on carb. Was set way lean. Broke out the timing light, only to find it was broken. Got a new one and saw that the motor was WAY advanced, like more than 30 degrees! have it to about 6 now and have the popping almost cleared up. Got too dark outside to keep sticking my hands around a hot running motor.

    Pop now is only at upper RPM.
     
  19. TexasDart
    Joined: Oct 11, 2007
    Posts: 853

    TexasDart
    Member

    Well sounds like you are getting close...maybe the mechanical advance springs in the distributor are weak or it's not working at all. Maybe someone else can chip in on how to diagnose that.
     
  20. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    It's vaccuum bit I'm starting to think it's in advance somehow.
     
  21. TexasDart
    Joined: Oct 11, 2007
    Posts: 853

    TexasDart
    Member

    The diaphram may be broke. Not really sure how the 351s work. You might take off the vacuum line and plug the vacuum line and see if it changes the upper RPM problem. If not then the Vacuum advance may be bad. You can probably by a new one.
     
  22. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Vac advance is good according to **** test. It's a magnetic pickup dizzy so nothing in there to be stuck as far as I know.

    Guess I might be trying to check vaccuum and or rockers/cam
     
  23. TexasDart
    Joined: Oct 11, 2007
    Posts: 853

    TexasDart
    Member

    You might watch your timing as you rev it up...see if it's jumping around a bunch. Maybe you have slop in your timing chain or distibutor. If it's 'popping' ie..back firing at upper rpms..the timing may be changing.
     
  24. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Getting the distinct feeling after looking at more wiring and junk, the electronic fuel pump might not be putting out enough juice. has 2 inline filters on it, and a horrible mess of wires and splices running to it,, so perhaps thats the issue. will be checking filters and rewiring a bunch of stuff tonight.
     
  25. TexasDart
    Joined: Oct 11, 2007
    Posts: 853

    TexasDart
    Member

    That would be a good thing to sort out. I would think that it you are not getting enough fuel at the upper rpms...ie...wot..then you would just fall on your face. But it's still good to get it cleaned up.
     
  26. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Pulloed out tons of ****py wires last night. have a lot of it fixed and plan to ****on up the rest tonight.
    Got a new fuel filter, fuel pressure regulator and a fuel pressure guage.
    hopefully after this i'll have it all narrowed down enough to start in on something different on the truck
     
  27. chevyshack
    Joined: Dec 28, 2008
    Posts: 950

    chevyshack
    Member

    Is this a 351 windsor, modified, or cleveland? Maybe i missed it somewhere. It could be a firing problem under load.
     
  28. OahuEli
    Joined: Dec 27, 2008
    Posts: 5,243

    OahuEli
    Member
    from Hawaii

    Be careful if you make this adjustment. If the worm gears are worn, adjusting out the slack can make the gears bind when turning around a corner. I found this out the hard way and left skid marks in my skivvies when the steering locked up in traffic.:eek:
     
  29. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    I'm going to give the steering adjustment a try, but quite carefully. I've heard the scarry stories of adjusting it too much, and the binding. My headders almost touch the box so thats no help i know. Looking for some stock 351 manifolds to put back on it, I need the clearance more than the headder
     
  30. FANTASY FACTORY
    Joined: Mar 6, 2008
    Posts: 256

    FANTASY FACTORY
    Member

    OK, as the towns resident carb guru, heres the dilly on eddy's.
    acc pumps wear out at a a rate of 2 per year, bores are left in as cast condition,
    pop in a new pump kit.
    unlike a holley, the jets cover the whole throttle spectrum, and thier location lends them to easy clogging,
    and as you can see, the idle mixture screws are hardly surgical.
    change the pump, hot tank the carb, polish the screws, you'll be fine,
    side note, eddies are inherintly jetted lean, fuel mix rods have 3 steps, go ONE richer in middle step as a start, I have gone 10.90 without touching jets!
     

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