excess valve train noise (LT1 solid lifters) - NCRS Discussion Boards

excess valve train noise (LT1 solid lifters)

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  • Duke W.
    Beyond Control Poster
    • January 1, 1993
    • 15663

    #16
    Re: excess valve train noise (LT1 solid lifters)

    Cold piston slap would probably have been there from day one as would a loose wrist pin that can also cause ticking. It's time to pull the valve covers remove some rocker arms and inspect. You might have a wear problem, but all anyone can do is give possible causes at this point.

    Duke

    Comment

    • Loren L.
      Extremely Frequent Poster
      • April 30, 1976
      • 4104

      #17
      Re: excess valve train noise (LT1 solid lifters)

      Does the motor in question have screw-in or press-in studs?

      Comment

      • Jerome P.
        Expired
        • October 22, 2006
        • 607

        #18
        Re: excess valve train noise (LT1 solid lifters)

        Thanks Duke. I also was thinking a possibly wrist pin, but also rationalized it as not a probable cause for the noise. I am just trying to get someone else's thoughts and also get some metal relief that it is not a real major problem. Hopefully it is not.

        Comment

        • Jerome P.
          Expired
          • October 22, 2006
          • 607

          #19
          Re: excess valve train noise (LT1 solid lifters)

          Originally posted by Loren Lundberg (912)
          Does the motor in question have screw-in or press-in studs?
          The engine is an original 350/255HP LT1 engine, but rebuilt. I believe the engine had and now has push-in studs. However, I am not 100% sure. Do you have thoughts either way?

          Thanks

          Jerry

          Comment

          • Duke W.
            Beyond Control Poster
            • January 1, 1993
            • 15663

            #20
            Re: excess valve train noise (LT1 solid lifters)

            All LT-1s had screw-in studs and guideplates as original equipment.

            So the engine has been rebuilt, eh? Did you supervise the work? ...have any documentation?

            You'd be surprised how many OE mechanical lifter engines get rebuilt with a stinking hydraulic lifter camshaft!

            Duke
            Last edited by Duke W.; April 28, 2009, 08:09 PM.

            Comment

            • Jerome P.
              Expired
              • October 22, 2006
              • 607

              #21
              Re: excess valve train noise (LT1 solid lifters)

              I miss spoke. After checking the repair work bill and the Corvette parts book I did receive new Valve Push Rod Adjusting assemblies including the screw-in studs. Part # 3973416 is for a screw-in stud for 70-72 Corvette with special high performance 350 engine and that is what is in the car.

              The cam is original equipment.

              I still am puzzled why I have the clicking noise on initial start up and then it goes away after 4/5 minutes. Any last thoughts? I will let you know what I find out when I take the valve cover off. Probably in the next 10 days to 2 weeks.

              Thanks again.

              Jerry

              Comment

              • Chuck G.
                Extremely Frequent Poster
                • May 31, 1982
                • 2034

                #22
                Re: excess valve train noise (LT1 solid lifters)

                Originally posted by Jerome Pederson (46381)

                I still am puzzled why I have the clicking noise on initial start up and then it goes away after 4/5 minutes. Any last thoughts? I will let you know what I find out when I take the valve cover off. Probably in the next 10 days to 2 weeks.

                Thanks again.

                Jerry
                Hi Jerry.

                As the engine heats up, metal parts expand.

                If you have any "excessive" clearances when the engine is cold, as the metal parts heat up, that excessive clearance goes away. That holds for the valve train, piston slap, etc.

                I'd guess you might find a few valve lash adjustments a bit too great when the engine is cold. I'll also bet that when you re-adjust the clearances properly, the clicking will go away.

                Chuck
                1963 Corvette Conv. 327/360 NCRS Top Flight
                2006 Corvette Conv. Velocity Yellow NCRS Top Flight
                1956 Chevy Sedan. 350/4 Speed Hot Rod

                Comment

                • Joe C.
                  Expired
                  • August 31, 1999
                  • 4598

                  #23
                  Re: excess valve train noise (LT1 solid lifters)

                  What weight oil are you using?
                  Agreed, that you may have a couple of tappets set too wide. Adjust using the procedure given to you.
                  On a cold engine, with both covers off, note how long it takes for oil to appear at all 16 rocker arms on initial startup.

                  Comment

                  • Stuart F.
                    Expired
                    • August 31, 1996
                    • 4676

                    #24
                    Re: excess valve train noise (LT1 solid lifters)

                    Are you REALLY sure you have solids?

                    Stu Fox

                    Comment

                    • Jerome P.
                      Expired
                      • October 22, 2006
                      • 607

                      #25
                      Re: excess valve train noise (LT1 solid lifters)

                      Originally posted by Stuart Fox (28060)
                      Are you REALLY sure you have solids?

                      Stu Fox
                      Yes for sure. I physically saw them.

                      Comment

                      • Clem Z.
                        Expired
                        • January 1, 2006
                        • 9427

                        #26
                        Re: excess valve train noise (LT1 solid lifters)

                        use a automotive stethoscope to locate which side is making the noise and then remove all the rockers arms and do a visual inspection of all the parts

                        Comment

                        • Loren L.
                          Extremely Frequent Poster
                          • April 30, 1976
                          • 4104

                          #27
                          Re: excess valve train noise (LT1 solid lifters)

                          If the studs are press-fit, start looking for one that's coming out, ie, "taller" than its buddies.

                          Comment

                          • Tim S.
                            Very Frequent User
                            • May 31, 1990
                            • 704

                            #28
                            Re: excess valve train noise (LT1 solid lifters)

                            Jerry,
                            As Duke mentioned, if you can isolate the noise to a given valve or cylinder, that would be the first step. After that, as mentioned, lash all of your valves noting variances in lash. Then, keep a close eye on any valves that had a larger clearance. This will allow you to to keep an eye for a cam lobe that may be going south. Best of luck!

                            Tim

                            Comment

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