Help with vacuum leaks!!!!! + 350 question!!!

Discussion in '40- & 55-Series Tech' started by nat, Feb 21, 2007.

  1. nat

    nat

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    So my new TBI is put together wired and runs, but I am sure I have a vacuum leak somewhere. I was meticulous installing the adapter plate and TBI unit, plus I have hardly anything hooked to vacuum sources and it is all new hose. Anyone have some good tips on finding what leaks??

    On a 330hp chevy 350................how many bolts hold down the intake manifold? I only see 8.
     
    Last edited: Feb 21, 2007
  2. bandy rooster

    bandy rooster

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    spraying brakleen or something similar around connections will usually find them.. if the engine revs up (rpms raise) you've got a leak where you sprayed


    what makes you so sure its a vacuum leak?

    intake manifold bolts? if your talking about the actual intake to the heads there is def more then 4 (maybe 4 on each side or 8 total)
     
  3. zebrabeefj40

    zebrabeefj40

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    Most SBC intakes are held down by 12 bolts - 6 per side...

    Nick
     
  4. nat

    nat

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    I miss typed.............I meant 8. There are 4 to a side that I can see. I have Vortec heads.

    I am worried because the bolts seemed loose, I want to re-torque it, but don't want to miss something.
     
  5. nat

    nat

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    With the key on, I jumpered the A&B terminals on the ALDL and then disconected the IAC plug. I fired up the rig and there was no change in the idle speed. It should have been lower.

    The other thing, is I set the base timing to 0 degrees (with the timing wire disconected) and the motor stumbles when given gas.

    I could adjust the throttle plates and timing, but I want to rule out vacuum leaks first.
     
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