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Correct way to use Sea Foam through vacuum lines??

Discussion in 'Maintenance & Upkeep' started by FergusonT, Sep 7, 2010.

  1. FergusonT

    FergusonT Rockstar 4 Years 100 Posts

    Sea Foam's website says that you can't pour it down the vacuum lines of certain GM Vortec engines because the lines do not distribute evenly to each cylinder. Does anybody know the correct process to do this with a 5.7L vortec? I am going to add it to the fuel and maybe oil...but just wondering if there is a way to do the vacuum line process.
  2. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    Pull the line off the brake booster, hold the throttle to 1300RPMs or so, and pour in 3/4 of a can. With the motor idled up it will flow in very well, and let it sit for 2 hours. And then take it for a drive and watch the smoke.
    This is how i have done it on all of the Vortecs that i have worked on (i have 3 of them and my buddies have 4 more that i do this to yearly) Thanks the the long idle times in the cold. You will notice a huge difference after you do it as well.
    Good luck and let us know how it goes.
  3. FergusonT

    FergusonT Rockstar 4 Years 100 Posts

    Alright, just a little nervous after going through Sea Foams website but I should be good to go. I will let you guys know, maybe get some pics of the smoke, if there is any!
  4. MightyMax

    MightyMax Rockstar 100 Posts

    Look forward to seeing it.
  5. ntbush83

    ntbush83 Rockstar 4 Years ROTM Winner 1000 Posts

    I just used the sea foam spray on my vortec 6.0 and it worked great. they make the special hose that goes into the throttle body next to the throttle plate. Thats what the recommended way of doing it is.
  6. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    With the 6.0L the intake runners are different as well. So i have seen this but i have found on that on the 5.7L it is easier and works best to go thru the brake booster, since the hose didnt seem to provided the same results.. But that is also an opinion since i havent removed the top end of the motor to verify...
    But either way should do the trick
  7. ntbush83

    ntbush83 Rockstar 4 Years ROTM Winner 1000 Posts

    I noticed you said to wait two hours before you drive. Does the longer you let it sit the better job it does?
  8. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    Well it eats the carbon up. so most of the people who have used it have agreed that a minumum of an hour does much better than the reccommended 20 minutes. it is like any cleaner if you let it sit for a bit more it will clean it better. since i have done the the lower time with minimal results as compared to the longer time.
  9. FergusonT

    FergusonT Rockstar 4 Years 100 Posts

    So how about putting it through the brake booster line and in the gas simultaneously?? or is it best to do it at separate times?
  10. ridick_bowen

    ridick_bowen Rockstar 100 Posts

    Will this affect my new synthethic oil that I just put in my motor. Or does this process only feed thru the upper head and out the exhaust?

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