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th400 to manifold vaccume? How do I fix?

Discussion in 'The Garage' started by 78Suburban, Apr 5, 2006.

  1. 78Suburban

    78Suburban 1/2 ton status

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    I knew the rubber was a little cracked on this thing. I'm not sure if a vaccume leak would have caused all the terrible performace problems I've been having. And before I rebuilt my carb, I could put my hands over it, and the idle speed would not increase, which led me to belive I didn't have a vaccume leak. Is this meathod fool proof? And I never had the idle increase spraying this bad boy with carb cleaner. Now that I've rebuilt my carb, I had a small vaccume leak, and now that I've corrected the vaccume leak, it won't fire up and run anymore :crazy: (the air horn screws weren't tight enough, and now that they are tight, no idle :confused: ) Now its backfiring through the carb alot more too, even when I try to crank it.



    Long story short, I know I have a vaccume leak now, because I got curious and have this little line a tug, and it pulled on out of the manifold. So can I get another little rubber sleeve to slide over it from the parts store? The t-fitting that comes off of it goes to the Air Conditioner's climate control box (I'm seriously considering pulling the AC anyway, so I may end up plugging this off. I don't know if this could cause the engine to stumble severly and poof through the carb, especially under load and over half throttle... BUT I KNOW, THIS ISN"T A GOOD THING

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    thanks,
    James
     
  2. muscle

    muscle 1/2 ton status

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    new piece of vac hose... done deal
     
  3. 78Suburban

    78Suburban 1/2 ton status

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    So all that is is a small length of vaccume hose?? It doesn't requre some specially shapped rubber piece? cool :bow:
     
  4. Chevy305

    Chevy305 6 Lug 14bsf Status Premium Member GMOTM Winner

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    you'd be surprised how much a 2in piece of hose matters.
     
  5. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    If you put your hands over the carb and it doesn't die then you have a big vacuum leak somewhere or possibly several small leaks. The reason the engine didn't die was because it was getting air from somewhere else IE: vacuum leak.
     
  6. 78Suburban

    78Suburban 1/2 ton status

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    well, before I rebuilt the carb, it would choke the motor out.. then afterward it wouldn't, because I hadn't tightened the screws on the carb down enough...I replaced the link with vaccume hose... but I've got a bigger problem on my hands now... the fun rocker :bow:
     

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