Tinking Sound...

Discussion in 'Rotating Assemblies' started by DorianL, May 10, 2020.

  1. DorianL

    DorianL solid fixture here in the forum Staff Member

    Greetz All :cool:

    While I am in the process of rebuilding the 2000 engine, I need to work on my current motivator.

    Four things about it are bothering me:
    1. Valve guides may be old - rapidly shaking vacuum gauge needle at idle (18-21 inches) and a blue puff of smoke only at start.
    2. Leaking rear main seal - well; it seems to be coming from there o_O
    3. Vibration - jury is still out on that one... it could be related to point 4.
    4. Tinking sound...

    Now, I want to address each one... but the tinking is one that baffles me. I replaced the cam recently as well as the lifters. With the valve covers off, the rockers seem to be operating normally. Exhaust temps are all in the same ballpark.. I set the valve lash hot... and yet I am getting a very distinct "TINK" sound that I hear very clearly around cylinder 8 with an automotive stethoscope. Now it sounds distinct... but not really audible without the stethoscope.

    As far as I know, the only think there the could make such a noise is the cam slapping the bottom of a lifter... but the cam and lifters are new.

    Anything I can do short of yanking the intake ?

    It doesn't sound like a bearing; seems to be coming from higher up and a different sound.

    At worst, I may be living with this until the other engine is ready.
     
    Last edited: May 10, 2020
  2. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    any time you find the valve train producing a noise its generally a clearance issue or a worn part,
    to help locate the source of the noise, take off the valve cover and, have a buddy start the engine,
    press down on the rockers individually at idle with the palm of your hand,
    ,if the lifter, rocker or other valvetrain component is worn or mal-adjusted,
    the sound on each valve assembly will change as pressures applied to the rocker with the heel of your hand on the rocker testing individually at idle,
    obviously done before oil temps rise too far and
    visually check for cracked valve springs,
    bent or loose rocker studs and
    rocker slots that contact the rocker stud

    and
    missing valve lock keys in the valve spring retainer
    Id also suggest you swap rockers if you find one causing the noise,
    burn or worn rocker balls in the rocker can cause this,
    and that helps you isolate the defective component

    https://www.chevydiy.com/small-block-chevy-rocker-arms-studs-pushrods-lifters-guide/

    [​IMG]

    Stamped rockers use a slot cut in the base of the rocker that allows the rocker to move relative to the stud. With higher lift cams,
    make sure there is a minimum of 0.050 inches clearance between the end of the rocker slot and the rocker stud at max lift.


    [​IMG]

    a burn rocker ball can result from lack of volume of pushrod oil flow,
    this tends to temporarily result in galling and a rough surface,
    rocker balls with grooves tend to allow more oil flow to the rocker ball bearing surfaces thus a marginally lower failure rate due to galling

    [​IMG]

    [​IMG]
    [​IMG]
    check all valve train geometry and clearance on any engine you assemble or modify the valve train on.
    [​IMG]

    In the mid 1980s, all production small blocks began using “guided” rocker arms that use two small guides that straddle the valve tip to locate the rocker arm tip. Guided or “rail” rockers should not be used with guideplates since this could create a binding situation that would break parts.
    its not unusual to find mixed sets on older engines:mad:



    let us know what you find:rolleyes::p
     
    Last edited: May 10, 2020
    DorianL likes this.
  3. DorianL

    DorianL solid fixture here in the forum Staff Member

    Hmmm. Of course ! I never thought to check that way or those components :rolleyes:

    I am looking FW to checking this out.
     
  4. Loves302Chevy

    Loves302Chevy "One test is worth a thousand expert opinions."

    Dorian, stick one end of a length of vacuum tubing in your ear and probe around with the other end. You can really pinpoint noises this way. The sound you describe sounds like could be an exhaust leak. They sound exactly like what you described.
     
  5. Loves302Chevy

    Loves302Chevy "One test is worth a thousand expert opinions."

  6. DorianL

    DorianL solid fixture here in the forum Staff Member

    It really sounded metallic... something slapping something else.

    If the weather is good, this afternoon I'll check it out.

    Yes... I think I read loose valve guide. Since I am planning a rebuild within 12 months, none of this is a deal breaker. It's just that vibration that annoys me the most.
     
  7. rlphvac

    rlphvac solid fixture here in the forum

    If its something easy fix it if its a big deal buy earplugs and know you will have a new motor in it shortly but in my opinion if you did a cam change look at the top end something worked loose or maybe didn't tighten right and went out of adjustment
     
  8. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    I would not rule out a loose flywheel or flex plate, or converter bolts , in your search for the source for that tinking sound
     
  9. rlphvac

    rlphvac solid fixture here in the forum

    You are right Grumpy chasing sounds can get interesting a friend asked to use my garage to find a brake noise that according to him was the left front pads making the noise I didn't agree with his choice of pulling the front wheels as there was no brake dust on either of the front wheels so he pulled the left front it was OK then pulled the right front again OK again then pulled the left rear again it was OK then pulled the right rear and said that it was OK then I looked at all the metallic dust on the rim and found out it was that side E brake making the noise so in hindsight I should have test rode it but aren't totally sure I would have called it any different
     
  10. DorianL

    DorianL solid fixture here in the forum Staff Member

    :confused::confused:
    yeah I got a squeaking sound too that sounds like it’s coming from the left front brake... but, I’m not sure it’s that. It could easily left e-brake :confused:
     
  11. rlphvac

    rlphvac solid fixture here in the forum

    And we have that kind of setup on Vettes LOL
     

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