350 sbc runs rough and blows smoke

Discussion in 'Engine Topic' started by Justin Berke, Jan 16, 2019.

  1. 1980RS

    1980RS Veteran Member

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    Yup the early Demons did have that trouble for sure. I am not a fan of Quick Fuel carbs, my son had one on his 409 and it ran so fat at idle it made your eyes water. Called QF and got the lean is mean speech, then I told the guy that a washed down cyl was just as bad and tell me why out of the box on a new carb that the throttle blade exposes almost .080 of the idle feed restrictor (t-slot). Nothing but mice sounds. If you want that carb to idle right you may have to add a restrictor in the main body, it's not too had to do otherwise get a Holley.
     
  2. Justin Berke

    Justin Berke New Member

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    Hmm
     
  3. Justin Berke

    Justin Berke New Member

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    So I've ruled out everything except the carb. The float bowls immediately fill when the fuel pump is on and I think it is a stuck float. Will be taking apart the carburetor this weekend
     
  4. roadrace2

    roadrace2 Veteran Member

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    whats initial timing set at? whats total? check that first then carb/fuel issues. my opinion.
    *you mentioned "timing is fine" - could you provide your specs?
     
  5. Bandit723

    Bandit723 Veteran Member

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    Car idles fine with no fuel pump turned on and runs poorly when the pump is turned on - not sure what timing has to do with that....just saying
     
  6. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    The bowls are supposed to fill immediately when you turn the pump on, that doesn't mean a float is stuck. Did you do the test I suggested in post# 21? This will tell you if a float is stuck. Also, I'll ask again - is the 7psi you referred to set by a regulator or advertised output of the pump?

    We don't seem to be making any meaningful forward progress, just jumping around on this issue. Diagnosing issues like this need to proceed in order. You said timing is not the issue but you have not provided any timing information after repeated request. Any of us that grew up frequently changing/adjusting points and timing know that you need to have timing set correctly before tuning on the carburetor. I'm not saying that timing is the issue, but it needs to be eliminated.
     
  7. Justin Berke

    Justin Berke New Member

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    The car idles fine without the fuel pump on, timing is not the issue. Flooding is the issue. When the fuel pump turns on fuel fills the bowl completely to the top. Secondary bowl is fine.
     
  8. wiseryder

    wiseryder Veteran Member Lifetime Gold Member

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    Slap a different carb on it, that will narrow it down
     
  9. Bandit723

    Bandit723 Veteran Member

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    Flooded fuel bowl has to be a timing issue Lol.....Hope the sticky float is an easy fix.
     
  10. 1980RS

    1980RS Veteran Member

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    Like I said earlier have seen it only had flooding issues with the QF carbs. I am betting it's the secondary side on his also.
     

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