cannot get dual carbs to idle right...
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cannot get dual carbs to idle right...

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    Junior Member johnkoopa's Avatar
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    Default cannot get dual carbs to idle right...

    Just bought my first boat and I am in a little over my head.. but that's why they have this great fourm I suppose..From what I know its a 74 Tahiti with a 454.Here is the problem I am having, I have two edelbrocks that I dunno if they need to be rebuilt.When I start the boat it seems like it will not idle any lower then 2500..I took of the linkage to see if it had something to do with that but it was the same..
    They have electric chokes that are not hooked up, it seems like the butterfly don't close enough..
    Another thing i noticed was the air flow mixture screws seemed put of wacky
    I will try and post a pic..
    This is my question.. should I just take the dual carbs off and put a smaller intake and carb for the boat to be more reliable? Or is it just something I need to have tuned?
    Thanks in advance for all the help guys..

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    Cas
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    I went through the same thing a couple of years ago with the Edelbrocks, just couldn't get a good idle below 2K. In the end, it was found that one of the carbs had an interior crack in the idle circuit of the casting. Have you pulled the tops of the carbs off to see if there is any junk in the bowls? If there is, rebuilds may be needed
    Have you checked the fuel pressure? Edelbrocks don't need any more than about 5.5 lbs of fuel pressure. Any more than that may cause flooding and the engine won't idle
    A couple of simple tests is to swap the needles side to side on each carb, one at a time. This is, swap the needles and start it to see if it makes a difference, if it does, you'll know there might be some debris in the carb, a bad needle or a bad seat. From there, try pulling the needles and blowing it out with compressed air.

    I ended up replacing the Edelbrocks with Holley's for a couple of reasons, one of which was the Edel rebuild kits were like $65.00 each. I wasn't about to spend $130.00 on the rebuilds, would rather put the money towards a couple of new carbs. There are a couple of really good carb shops around but I purchased mine from Bigs Performance back in Missouri. As with other companies, Bigs builds the carbs to your engine specs, flows and dyno's each carb so they're a plug and play when you get them.

    A friend of mine is also looking to trade a couple of rebuildable Holley's for a couple of Edelbrocks. if interested

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    best thing to do is sell those carbs on e-bay and buy two vac. secondary holly 650's. thats what i have on my boat and they work GREAT. with edeljunk's it takes one tiny little thing to plug up the jets in those carbs. i have yet to see any edeljunk to be reliable on or off the water... i rebuilt my own carbs an was nothing to adj. the flots and idle for it and she idles right @ 800 rpm i've had the motor die on me once when i let out of the throttle... a very reliable carb and a better name!!! if you want to see the carbs hit me up on f.b. @ [email protected]

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    Senior Member jetboatperformance's Avatar
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    Sounds like a simple big a$$ vacum leak but ,Just curious How much Cam (specs) is/are in this motor if you know ?

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    Senior Member swtd's Avatar
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    Default carbs

    Quote Originally Posted by johnkoopa View Post
    Just bought my first boat and I am in a little over my head.. but that's why they have this great fourm I suppose..From what I know its a 74 Tahiti with a 454.Here is the problem I am having, I have two edelbrocks that I dunno if they need to be rebuilt.When I start the boat it seems like it will not idle any lower then 2500..I took of the linkage to see if it had something to do with that but it was the same..
    They have electric chokes that are not hooked up, it seems like the butterfly don't close enough..
    Another thing i noticed was the air flow mixture screws seemed put of wacky
    I will try and post a pic..
    This is my question.. should I just take the dual carbs off and put a smaller intake and carb for the boat to be more reliable? Or is it just something I need to have tuned?
    Thanks in advance for all the help guys..
    I have 2 vacumm 750 holley with fuel lines for sale here in adds.

  8. #6
    Senior Member Widetrack's Avatar
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    Quote Originally Posted by jetboatperformance View Post
    Sounds like a simple big a$$ vacum leak but ,Just curious How much Cam (specs) is/are in this motor if you know ?
    X2


    SOMEONE SAID YOU CAN'T TAKE IT WITH YOU! SO,IM BURNING IT UP ONE GALLON AT A TIME!
    WT

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    Junior Member johnkoopa's Avatar
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    Default pics

    thanks for the advice guys... i just got back in town so i am going to try and tinker with it today..

    here are a couple pix...
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  10. #8
    Junior Member johnkoopa's Avatar
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    one more..
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    Junior Member renegade's Avatar
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    Cool dual edelbrocks

    Well if every thing is sound with motor. pull the tops off and carefully blow the 4 jets that are in there with compressed air.also check your needle and seats for shit build up.make sure you dont rip the gasket when you pull the tops. i have 2 edelbrock 750s and they idel great.good luck and have fun.

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    Seriously off center slowride's Avatar
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    I tried blowing up one of your pics but couldn't tell, so I'll be Capt Obvious and ask.... did you plug/cap the 3/8" vacuum nipples on the front of the carbs?






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    Senior Member jetboatperformance's Avatar
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    Still curious about the Cam specs as cams can wreak havoc with idle , also you may want to reconsider the Vacum advance , could be part of the overall isssue Tom

  14. #12
    Cas
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    Quote Originally Posted by slowride View Post
    I tried blowing up one of your pics but couldn't tell, so I'll be Capt Obvious and ask.... did you plug/cap the 3/8" vacuum nipples on the front of the carbs?
    unless he has the 1410 marine carbs which don't have the vacuum ports which leads to something else. If they are the marine 1410's, someone could have drilled out one of the small holes in the front attempting to get vacuum for the distributor

    1410-


    1406
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