Question about 1999 Chevrolet Silverado 1500

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Possible Rod Knock

I recently used the product, SEA FOAM in my air intake system. The seconed I dropped it into the line that comes off the brake booster, I began to hear a "Knock". The truck runs great and I am getting mixed reviews on what the problem could be. I am also having a tough time finding the source of the Knock. Could what I did, cause a rod to bend? It is consistent with the RPMS on the engine, increasing speed of knocking.

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  • ccn7 May 11, 2010

    I would go with the loose carbon. came off top of piston.

  • Dave  C
    Dave C May 11, 2010

    Does this product come with any kind of limiting orifice so that you can only put it in slowly, or did you put the booster hose right into it?

  • gerry bissi May 11, 2010

    engines do not like liquids. Tehy don't compress in the cylinder, but the rods will bend. It depends how much liquid you sent into the combustion chamber. Disconnect one spark plug wire at a time, and the one that makes the nosie go away, is the problem cylinder.

    Hydrolock is a very common problem when people try to drive through foot deep water too fast. They splash the water up and **** it into the air intake and destroy their engine. Sometimes, this is covered by their insurance company.

  • Samuel Charles Spriggs May 11, 2010

    Just a wild guess, here. It could be that this super detergent cleaned enough carbon build-up off something that it became loose and started knocking.

    It wouldn't cause a rod to bend. If it got into your oil, it could clean off carbon deposits and cause the bearings to become loose and start knocking. That's why super detergents are not recommended for high mileage engines -- sometimes they do more harm than good.

    How would the seafoam have gotten into the oil?

    What are some of the opinions you've heard as to the cause of the knock?



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You've done some Mischief to the engine. However in your defence i think it more co-insidance that it happened at that moment. Sounds like you threw a rod. OOOOPPPPPSSSSS!!!!!! Steve in UK

Posted on May 13, 2009


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