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At my wits end with this 2GC....

Discussion in 'Early CJ5 and CJ6 Tech' started by PostaljeepSS, May 5, 2015.

  1. May 5, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
    Joined:
    Jun 22, 2008
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    86
    Good morning. I'm having a hell of a time with the 2GC carb on my 225. It used to run rich but would idle ok and miss a little at speed but was otherwise ok. I replaced the plugs, cap, and wires which helped a little. I replaced the fuel pump because it had failed and that's when the problems started. It was flooding and overflowing the carb. I added a pressure regulator and brought it down to 3lbs of pressure which helped the flooding but it was still running really rich and missing even at idle. I have now gone through 2 rebuild kits with all kinds of float adjustment and it's still flooding out and/or starving. I can remedy it with a couple love taps to the carb which is either knocking loose the float or the long shaft which I believe is the power valve? but this only works for a minute or so. I have tried penetrating oil and silicone spray on both but something is still getting stuck. Any other bright ideas before I give up on this thing?
     
  2. May 5, 2015
    Twin2

    Twin2 not him 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Virginia Beach, VA
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    Is it possible . you have a V8 carb
     
  3. May 5, 2015
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    cordele, Ga.
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    I would definitely suspect the power valve piston assy. Some times they have to be removed to clean them properly. They do have to move freely.
    Make sure the choke is not too rich and staying closed.
     
  4. May 5, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
    Joined:
    Jun 22, 2008
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    I'm reasonably sure it's not for a V8. It is the one that came with it, and it used to run fine, though I suppose that doesn't mean anything. I pulled the jets out and they have a 51 stamped on them. Some brief research shows 55 would be the stock size so it should be a touch lean as is? When you say the power valve piston are you talking about the one in the bottom of the float bowl or the long shaft on the spring? I have polished and lubricated that rod and it moves pretty freely. The one in the bottom of the bowl rarely gets stuck if I push it in the right way. I have removed that assembly, cleaned it, lubed it etc.
     
  5. May 6, 2015
    homersdog

    homersdog Tulsa, Ok 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Tulsa, OK
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    What float settings are you using? Metal or plastic float? How are you measuring it?
     
  6. May 6, 2015
    lynn

    lynn Time machine / Early CJ5 HR Rep Staff Member

    Huntingdon PA
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    Sep 20, 2002
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    I had some similar issues, replaced the accelerator pump and it cured it.
    HTH
     
  7. May 6, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
    Joined:
    Jun 22, 2008
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    86
    The float is one of those nitrophyl foam ones. I used the little measuring ruler that came with the rebuild kit. I have adjusted it a bit lower and higher. It doesn't seems to fit very well and isn't particularly buoyant. I have ordered an actual metal float, new power valve, and complete kit form Mike's Carburetor Parts which claims to be a made in America product instead of god knows from wherever the other ones came from. Hopefully it will be here by Friday so I can test it out this weekend.
     
  8. May 6, 2015
    blevisay

    blevisay Oh Noooooooooooooooo! Staff Member

    Portland Tn.
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    This is a long shot,but i have seen it. Try another float as the one you have may be fuel siaked.
    Hth
     
  9. May 6, 2015
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    cordele, Ga.
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    The 2GC has the automatic choke. Make sure it is holding the choke open when warm and above. These can be problematic and cause the carb to run rich.
     
  10. May 15, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
    Joined:
    Jun 22, 2008
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    I have the choke wired open for now. Thanks though! My rebuild kit came in a few days ago from Mike's Carburetors and I just finished it up an hour or so ago. I got the real float this time instead of that nitrophyl crap, a new power valve, new needle/seat, check balls etc. The overflowing seems to be eliminated! I also figured out I was tuning the the idle circuit on both jeeps incorrectly. I was using more idle speed to keep it going. I backed off the idle speed screw and adjusted the idle mix screws instead to get max idle rpm and then adjusted the speed screw down a bit more. I was able to back it off quite a bit which cleaned up a lot of the sputtering at idle and backfiring.

    It's not perfect though. It still smells a bit rich and I think the power piston is still getting stuck or not returning for whatever reason. I'm thinking the power piston pushes down at part or WOT and is getting stuck there. It seems to happen after revving the engine up and letting it come back to idle. It will some times stumble and only some times catch itself then start sputtering. A couple taps to the carb body with a hammer and it clears up instantly. Hoping to get a bit more time to tinker with it tomorrow. Maybe some emery cloth in the power piston bore?
     
  11. May 15, 2015
    Jeepenstein

    Jeepenstein Me like Jeep..

    North Central FL
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    Jun 15, 2003
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    I swear by these guys.. http://www.guaranteedcarburetors.com/ Like the ad says, plug and play.. I sent them the carb from my 78 D150, it came back looking like new, plopped it on, never touched a thing and it ran perfect right out of the box..
     
  12. May 15, 2015
    wrhirzel

    wrhirzel Member

    El Paso, TX
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  13. May 18, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
    Joined:
    Jun 22, 2008
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    Thanks for the websites! Unfortunately it doesn't matter too much now... I tore it apart again today and polished the power piston bore and the outside of the piston and added some light oil. It moved so much better! I put it back together and it fired right up and ran great. Gave it a couple revs at the carb it returned back to normal like a top. So the piston WAS at fault. I took it back off to put the heat spacer back in and apparently forgot to put the throttle return spring back on.

    I hopped back in, fired it up, and it went straight to WOT! It only took a second to process what was going on and kill it but the damage has been done :(. It now has a distinctive knock on the #1 or #3 cylinder. It seems to run ok but the sound is worrisome. I guess I get to spend my 3 day weekend screwing with that now. Here's hoping for a bent push rod and not something worse...
     
  14. May 18, 2015
    uncamonkey

    uncamonkey Member

    Greeley CO
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    Umm, poop, I hope it isn't too bad. One step foreward, 2 steps back. I do know what a V6 block can look like after parts start
    exiting out the side. Even as a V4 I got it off of the road.
     
  15. May 18, 2015
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    cordele, Ga.
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    What a shame.. Hope it's not too serious.
     
  16. May 19, 2015
    Southtowns27

    Southtowns27 Custom Title

    The Backhills of...
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    Where is the sound coming from? Up in the valve cover area or down low on the block? How's the oil pressure?
     
  17. May 21, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
    Joined:
    Jun 22, 2008
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    Well I have ok news and slightly better news. I tore into it today and found a stuck lifter. I took it out, lubed it, and gave it a few love taps which released it!. I put it back together and clunk gone. :) Not sure how long that will last but I'll let it ride for now. Total cost $24 for intake gaskets. I took it out and it was running great! I drove a couple bucks and got all the way up to 50mph with no problems.

    I pulled back into the driveway and it immediately died. It fired right up but idle was bad. Sputtering on the right bank, really rich, idle mix screw not working etc. A few taps to the carb with the hammer makes it better for a minute. Just off idle it starves out but only if you ease into it. Pumping works ok. I managed to get a video.
    [​IMG]

    At this point I was literally searching for a bigger hammer to smash it. While digging in a pile for it I uncovered an old 2bbl I had pulled off the V8 for my DJ5 project. It happens to be a much newer 2jet. I figured why not and sprayed the bowl full with carb cleaner and pumped it through. I swapped it with my old one and it fired up relatively easily. I did a basic tune on it and it ran well!

    The only problem is the throttle attachment is different which causes interference with the manifold so the throttle can't open very far. I think the heat spacer will get me pretty close. It's also not compatible with my throttle cable. I'm curious if it'd be possible to swap the throttle shaft from the old to the new? Not sure if they have identical venturis or not. Either way I'll take a crack at it again Friday. Fingers crossed that lifter keeps behaving...
     
  18. May 21, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
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    Oil pressure is 25lbs cold and 19-20lbs warm.
     
  19. May 22, 2015
    Southtowns27

    Southtowns27 Custom Title

    The Backhills of...
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    Cool. I was trying to rule out a wiped bearing for you, but you already got that part figured out fb
     
  20. May 22, 2015
    PostaljeepSS

    PostaljeepSS Member

    Boise,ID
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    Thanks anyway sir!
     
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