Valve Chatter

Discussion in '40- & 55-Series Tech' started by Nomis, Aug 24, 2006.

  1. Nomis

    Nomis

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    I've adjusted the valves 3 times now and still have a rythmic tap-tap-tap that is RPM dependent coming from the valve-train. I adjusted one set of valves at TDC and then rotated 360* and adjusted the other set - all while the engine was HOT but not running. .008 intake .014 exhaust.

    Is it possible to adjust the valves correctly and still have chatter? I have what sounds like a single rocker clacking away - more so at full throttle. Could a bad pushrod or rocker arm adjusting screw cause this? I didn't want to over-tighten things.

    I still need to narrow it down and identify exactly which rocker is making the noise and then go from there. I tried to find it with the engine on and it squirted hot oil at me so I shut her down and performed the adjustments with the engine off. I may try to check it again with the engine running again later.
  2. projektdotnet

    projektdotnet

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    YES! Check your oil level or even see if the top part of the motor is getting oil. Low oil can easily cause valve chatter (although fords are much worse than toyota in this sence ;))
  3. bandy rooster

    bandy rooster

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    does it sound like a sewing machine?
  4. Nomis

    Nomis

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    Oil delivery is good - no problem there.
  5. Nomis

    Nomis

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    It would if it weren't for the tapping sound. I'm going to use a piece of 1/2" rubber hose to ID the noisey rocker and adjust it from there. I'm also going to find TDC on that particular cylinder when I adjust it just to make sure.
  6. fjwagon

    fjwagon

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    Try doing a compression check and see if you all of them are are about the same.
  7. Fast Eddy

    Fast Eddy SILVER Star

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    Are you 100% sure it's not an exhaust leak? Same sound. Same area of the motor. Louder at higher rpms.
  8. PAFJ

    PAFJ

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    Mobile, AL
    I've been going through the same thing. Keep adjusting and adjusting...still have the chatter. Compression split is no more than 5 between all cylinders. For a long time I thought it was a valve problem; however, like Fast Eddy mentioned...I'm pretty sure at this point it is an exhaust leak, plus I can smell exhaust in the cab when I'm at a stop light. I'm going to pull my intake man...resurface, put on new header, gasket etc. and go from there. After all that work...I'm hoping it fixes the problem.


    :cheers:
  9. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

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    Then something is not correct.


    Even with 65 pounds of oil pressure when the 15W-40 oil is hot on engines that I adjust the valves on, you can run the truck at 1500-2000 rpm and you will not get oil squirting out at you from any of the rocker arms. I would verify that all the rocker arms are getting oil. Each arm has a hole in it that oil should dribble out from when the engine is running. If oil is shooting out from one, I would verify that the other rocker arms on that shaft are getting oil. You may find that your noisy rocker arm and valve assembly are not getting lubricated properly.


    Also,

    Have you run a torque wrench across the bolts that retain the rocker shafts and arms to the head? I have found that some of these bolts can loosen up over time and this will affect the accuracy of the valve settings.


    Also as has been suggested, a compression check would verify that all the valves are closing properly and that you do not have a valve slightly hanging up and not completely closing properly.



    Good luck!


    -Steve
  10. rgentry

    rgentry

    Messages:
    695
    Also, I would check to see that each of the push rods is spinning. If one or more are not spinning as the engine runs, it may be a sign that the lifter and or push rod is damaged. I actually don't know that they are supposed to spin, but every cruiser engine I have every worked on has had spinning push rods.
  11. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

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    The push rods/tubes are supposed to rotate...

  12. Nomis

    Nomis

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    I located the noisy rockers with a piece of tubing up to my ear and the other end by each of the rockers with the engine running. I had 3 rockers that were on the loose side. I checked with the engine on again this time and it did not squirt me - weird - maybe there was a piece of debris in there last time or maybe I mistook a splatter for a squirt, as it only happened once? I checked and there is a steady trickle of oil out of each rocker oil hole - good. I shut her down and adjusted the 3 rockers and now the rockers are dead quiet at idle.
    I still hear a faint tapping under WOT at high RPM. Interestingly, there was some side to side slop in some of the rods under the adjusters. And some of the rods did not rotate with the engine running - I don't remember if these are the same rods with side to side movement or not. I'm wondering if they were adjusted too tight in the past and may be out of round now?
    How difficult is it to remove the push rods? Can I just remove the adjusting bolt/screw and slide the rocker to the side and remove the push rods?
  13. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

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    You have a solid lifter engine....there is going to be a little valve noise.... ;)




    Some of them will come out that way....# 1 and #12 will not for sure..


    It is not that big of a deal to remove the rocker shaft assembly, remove the push rods and roll them on a flat surface to verify that they are all strait...


    Oh, and tap them on a hard surface also a couple times...they should ring and not make a thud sound..


    Good luck!


    -Steve
  14. Nomis

    Nomis

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    Thanks Steve.
    I posted a sound clip of my engine at startup and running. The air pump is making a little noise as it is not connected to anything right now so that high pitched clicking is the pump, not the rockers. Other than that the engine itself sounds fine to me.

    http://media.putfile.com/2F-Startup
  15. Man Stuff

    Men are not supposed to know what sewing machines sound like.
  16. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

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    Did you mom clean your room this morning also?
  17. PabloCruise

    PabloCruise SILVER Star

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    Heh heh heh, funny shtuff...

    Steve, when you say the rods are supposed to ring and not thud, what does that mean if they thud?
  18. Nope

    In all reality, I sew, I took Home economics back in school. I was busting his balls.
  19. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

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    That the weld holding the ball or cup on the end of the tube has cracked and usually allows oil to get into the tube....
  20. Nomis

    Nomis

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