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1960 Lark VI clutch/gearbox chatter

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  • Clutch / Torque Converter: 1960 Lark VI clutch/gearbox chatter

    Ok.

    So, my Lark is making a slight scrapping/chattering/rattling noise when running at idle. I can clear it up by simply resting my foot on the clutch pedal or, if I crawl under the car, by grabbing the clutch actuator arm and applying slight pressure back. The noise is somewhat intermittent; I notice that it seems to come and go, or I simply become accustomed to it, then notice it again. It's more noticeable if I'm sitting next to another car or in the garage where the sound is reflected up to the cabin; it's not very loud.

    A few things about this car:

    - 170ci L-head, 3-speed manual (no OD)
    - It is a daily driver, so fixing it before it becomes a huge issue is important to me.
    - The clutch was rebuilt about 1,000 miles ago...friction and pressure plates replaced, pilot and throw-out bearings replaced, flywheel turned down, and all the gearbox seals were replaced as well. The mechanic that performed the work noted no issues in the gearbox save the usual wear to the first and reverse gears. He is intimately familiar with Studebakers, so I trust that he knew what he was looking at.
    - The U-joints were replaced around the same time
    - Gearbox fluid is Ford Tractor mineral gear oil (SAE90) and brand new
    - Grease fittings are all regularly attended to.
    - Pedal free play is set correctly per the shop guide: between 1/2" to 1"
    - The sound, from under the car, seems to be coming from the vicinity of the gearbox, not the engine.
    - I am unable to find anything loose in the clutch linkage that appears to be making this sound; it definitely seems to be internal (somewhere)

    Gear engagement seems ok, but this is the first and only Stude I've driven: 1st gear from idle requires bumping 3rd to avoid grinding 1st. Downshifting from 3rd to 2nd is somewhat problematic; I have to be doing under 20mph and let it slip into gear (applying pressure upwards until the gear simply falls into engagement), otherwise 2nd will engage rather roughly. There is no whining or other noises that seem out of the ordinary for a car of this vintage. All in all, the car is relatively quiet.

    I think that's it. I'd appreciate anyone's input here. I'm not eager to tear into the gearbox looking for gremlins if I can avoid it...

  • #2
    Update:

    I did some additional troubleshooting and found that the noise is present on startup, intermittent in rhythm, but seems to clear itself up within twenty seconds or so. If I then actuate the clutch, or simply rest my foot on the pedal and remove it, the noise returns then disappears again as above. If I get under the car and play with the linkage, moving it back and forth, the noise returns, but if I tap on the release rod (the adjustable one) it appears to stop the noise.

    Again, I find nothing obviously loose or visibly vibrating.

    Comment


    • #3
      Welcome to the Forum, Spence.
      It looks like the noise comes from the throw-out bearing. You should try to exert just a light pressure onto the clutch pedal to make it touch the fingers of the pressure plate. If the noise appears at this moment, I would say that it is the culprit. A simple 5$ mechanic stetoscope would help you to make the diagnosis. If you did not have this trouble before the overhauling of the clutch, the answer to this is in the new parts.
      Nice day to all.
      sigpic

      Comment


      • #4
        Originally posted by christophe View Post
        Welcome to the Forum, Spence.
        It looks like the noise comes from the throw-out bearing. You should try to exert just a light pressure onto the clutch pedal to make it touch the fingers of the pressure plate. If the noise appears at this moment, I would say that it is the culprit. A simple 5$ mechanic stetoscope would help you to make the diagnosis. If you did not have this trouble before the overhauling of the clutch, the answer to this is in the new parts.
        Nice day to all.

        If I slowly apply pressure to the pedal, enough to take up the free play, I can hear it slightly for a fraction of a second. When I remove my foot, it makes it for a second or two, then it clears up again. Do I need to have this bearing replace again? The old one used to make a metallic ringing noise when I disengaged the clutch...I don't recall the old one doing this though.

        Comment


        • #5
          I would suspect the throw out bearing, possibly not clipped to throw out fingers. also bearing could be dry,re-boxed old stock Luck Doofus

          Comment


          • #6
            Originally posted by doofus View Post
            I would suspect the throw out bearing, possibly not clipped to throw out fingers. also bearing could be dry,re-boxed old stock Luck Doofus
            I bought it from Studebaker Parts here in Phoenix. It looked to be a new one to me, but it was in a generic box, so I suppose it might have been reboxed as you say.

            Not sure if it's related, but another intermittent issue I've got is when depressing the pedal to the floor, the last bit of travel will sometimes creak, audibly, and I can feel a slight resistance in the pedal. It comes and goes; sometimes it'll happen all day, sometimes only once or twice, or sometimes not at all for a week. I haven't noticed if it coincides with this noise though.

            Comment


            • #7
              Originally posted by MrBulldops View Post
              If I slowly apply pressure to the pedal, enough to take up the free play, I can hear it slightly for a fraction of a second. When I remove my foot, it makes it for a second or two, then it clears up again. Do I need to have this bearing replace again? The old one used to make a metallic ringing noise when I disengaged the clutch...I don't recall the old one doing this though.
              As suggested by Doofus, NOS bearings can't be trusted when still filled with the original grease. As far as I know these bearings can't be refilled but it's worth checking. Sometimes, it is possible to use a syringe to insert grease or heavy oil, but lightly as you don't want to ruin your new clutch disc with oil projections. I think I would wait a little to see if the if the noise is becoming worse or not. My Mercedes 230 E is making the same little sssshh noise since 40000 km!
              sigpic

              Comment


              • #8
                Originally posted by MrBulldops View Post
                Ok.


                Gear engagement seems ok, but this is the first and only Stude I've driven: 1st gear from idle requires bumping 3rd to avoid grinding 1st. Downshifting from 3rd to 2nd is somewhat problematic; I have to be doing under 20mph and let it slip into gear (applying pressure upwards until the gear simply falls into engagement), otherwise 2nd will engage rather roughly. There is no whining or other noises that seem out of the ordinary for a car of this vintage. All in all, the car is relatively quiet.

                I think that's it. I'd appreciate anyone's input here. I'm not eager to tear into the gearbox looking for gremlins if I can avoid it...
                Don't want to insult your intelligence by lecturing you on something you already know. But in case you don't:
                1. You only have synchromesh in 2nd and 3rd, which is why it grinds going into 1st. By bumping 3rd or 2nd, you are using the synchronizer in one of those gears to slow things down so first gear will engage. By doing so, you are (very slightly) adding wear to that synchronizer. Another option would be to just wait a few seconds with the clutch on the floor before dropping it into 1st.
                2. You are experiencing a bit of trouble downshifting from 3rd to 2nd because: (a) you are doing it at too high a speed or too quickly, (b) your 2nd gear synchronizer is somewhat worn, or (c) some of both of the above. You might try double clutching when downshifting to 2nd above about 10 mph. It's something some of us geezers learned driving worn-out cars years ago.

                Your car appears to have normal wear -- except for the throw-out bearing, it might go another 50K in that condition.
                Skip Lackie

                Comment


                • #9
                  Thanks to all for your input. I'll ride on it awhile and see if it gets any worse. The mechanic the rebuilt the clutch thinks it could be a bearing in the gearbox, but concurs the it's unlikely to require a rebuild for some time.

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