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  1. #1
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    Default 76 shovelhead top end noise

    So recently had an oil flow issue. Ran the bike a little without oil but not more than a mile. Pulled over and towed home. Fixed the oil flow issue but now my valvetrain is super loud more than normal. Sounds like ticking specifically in the front cylinder exhaust stroke. The oil fix included new lines, oil, and filter. As well with cleaning my pump and lifters/pushrods, they looked good. I have solid lifters, adjusted them so I can spin them in my fingers, no up and down play. I Have checked the adjustment multiple times. What would cause this noise? rocker arms? I think next I’m going to inspect the arms. this is a video of the noise.
    https://youtu.be/qylVKFFKKqM
    Last edited by Jacobzeise; 07-18-2019 at 7:06 PM.

  2. #2

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    Did you inspect the tappet rollers and cam lobes carefully? They are often the source of valve train noise. If all is good in the cam chest, next step is pull front head and cylinder, check rocker arms and valves and guides. Also check piston skirt for galling. If you do find a problem, pull the rear cylinder down as well, it probably won't be any better.

    Running a shovel motor for only a mile with no oil pressure will usually not cause any problems. I think your oil issues were more serious than that if that noise was the result.

    Jim

  3. #3
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    yes when i pulled them i looked for wear and damage and couldnt find any on the rollers and the cam lobe. this noise is definetly coming from the front rocker box. the rear one is fine. i guess next it to go thru the boxes. the noise didnt appear until i fully lost oil and then ran until it overheated.

  4. #4

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    If you overheated it with no oil pressure (and it would have taken way longer than one mile to do so), then you have probably galled a piston.

    Jim

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    Quote Originally Posted by JBinNC View Post
    If you overheated it with no oil pressure (and it would have taken way longer than one mile to do so), then you have probably galled a piston.

    Jim
    Yes sir, sound will travel for sure.........

  6. #6
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    Quote Originally Posted by JBinNC View Post
    If you overheated it with no oil pressure (and it would have taken way longer than one mile to do so), then you have probably galled a piston.

    Jim
    the noise doesnt intensify or speed up with throttle. it was a 95 degree day my engine was already riding 4th gear high rpms for a while before i lost pressure, then it was within 10 minutes after that i started to lose power and thats when i shut everything down and towed home.

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    Have you got a Bore Scope that you can lay your hands on ....??

    Last edited by Dragstews; 07-18-2019 at 3:02 PM.

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    Perform a compression test. Every mechanic should have at least one compression tester. Anything harsh enough to gall a skirt tends to affect compression.

    The cheap USB scopes which work with smartphones are rather handy, but if it fails a compression test it's time to snatch the top end anyway.

    There is never a downside to checking compression first which is why everything that comes into the shop gets checked and the readings noted on the work order.

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    Quote Originally Posted by farmall View Post
    Perform a compression test. Every mechanic should have at least one compression tester. Anything harsh enough to gall a skirt tends to affect compression.

    The cheap USB scopes which work with smartphones are rather handy, but if it fails a compression test it's time to snatch the top end anyway.

    There is never a downside to checking compression first which is why everything that comes into the shop gets checked and the readings noted on the work order.
    sounds good will do forsure. i did ride it around the block this morning and everything ran fine.
    Last edited by Jacobzeise; 07-18-2019 at 6:59 PM.

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    Could also be rocker side play?
    My 76 had that years ago, sounded like pushrods. In the end I tore into it and there was too much side play on the rockers.
    once I shimmed it into tolerances everything was nice and quiet.

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