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Technical Is this rocker arm wear excessive?

Discussion in 'The Hokey Ass Message Board' started by Century, Apr 11, 2020.

  1. Century
    Joined: May 28, 2009
    Posts: 176

    Century
    Member

    I have a Chevy 230 that was rebuilt 5k miles ago. Ran perfect until I accidentally tightened the rocker nuts thinking they were loose (coming from the nailhead world, I mistakenly assumed they were on a shaft). I realized right away and backed them all out and readjusted to 1 turn past zero lash. I've had a ticking ever since. I tried 1/2 turn past lash, 3/4 turn, adjusting while running, etc. Still chatters.

    I decided to pull the rockers, push rods, and lifters out to inspect. I found that the rockers had what looked to be fairly deep grooves - I have no way of knowing if they were replaced during the rebuild. The tops of the valves were flat and edges sharp (worn down?).

    Here are some pictures. Does this look right to you?

    I'm considering buying a new set of rockers. Not much I can do about the valves at the moment if they are indeed bad.

    valve train inspection 1.jpg valve train inspection 2.jpg valve train inspection 3.jpg valve train inspection 4.jpg
     
  2. squirrel
    Joined: Sep 23, 2004
    Posts: 48,278

    squirrel
    Member

    I hope you kept track of which lifter goes in which hole! You don't want to put them back on a different cam lobe, than the one they were running on.

    The rocker shown is worn. The valve stem still looks OK. I can't really tell about the lifters, and even with a good photo it's hard to tell exactly what shape they're in.
     
  3. SEAAIRE354
    Joined: Sep 7, 2015
    Posts: 245

    SEAAIRE354
    Member

    Yes the rocker is worn and would be about rite for one that had 100,000 miles on it not 5000. My guess is the old rockers were reused during the rebuild. Assuming that you were adjusting the valves correctly 3/4 turn should have quieted it up but I believe the spec is one fill turn although o never adjust then that tight. You may have a lifter plunger that is sticky and won’t take the adjustment.


    Sent from my iPhone using H.A.M.B.
     
    Driver50x likes this.
  4. 67drake
    Joined: Aug 8, 2008
    Posts: 145

    67drake
    Member
    from Avoca WI

    If you over tightened the adjustment that much, you might also want to check the pushrods. Roll on a flat surface to make sure they’re not bent.
     
    SEAAIRE354 likes this.

  5. I'm curious...if a rocker is overtightened, does it/can it do damage, or does it just hold the valve open? Of course, I realize that an open valve occupying the same space as a piston isn't going to work for long.
     
  6. TCTND
    Joined: Dec 27, 2019
    Posts: 220

    TCTND
    Member

    Do a leakdown test before anything else. You don't need to replace any of the valve gear for this. If the valves hit pistons while cinched down you could have bigger problems.
    regards,
    Phil
     
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  7. squirrel
    Joined: Sep 23, 2004
    Posts: 48,278

    squirrel
    Member

    probably not much chance of a valve hitting a piston in a 230....the valves are a long ways away

    head.jpg
     
  8. Century
    Joined: May 28, 2009
    Posts: 176

    Century
    Member

    I realized I was tightening an adjustable rocker pretty quickly and backed off.

    Am I good to throw a set of rockers at this?

    Also, the top of the valve stem looks worn flat compared to new one. Is this something to be concerned about?

    upload_2020-4-11_13-11-4.png upload_2020-4-11_13-11-39.png
     
  9. squirrel
    Joined: Sep 23, 2004
    Posts: 48,278

    squirrel
    Member

    I would try a new set of rockers. But if you moved the lifters around, the cam may or may not last a while.

    The chamfer on the valve tip is different on those two, but it's just a chamfer, and it doesn't really matter how wide it is.
     
    Truckdoctor Andy and VANDENPLAS like this.
  10. You could have a lifter that compressed and is stuck.

    your valves are worn and so is the rocker.

    I had a 305 in Chevy truck years ago that had a rocker that wore right through and the top of the valve was smooth and razor sharp.

    the engine surprisingly ran great.
    I put 1 rocker in and smoothed to edges of the valve with a deburring tool basically added a chamfer and took the sharp edge off
    And it ran good and quite for a long while
     
    Truckdoctor Andy likes this.
  11. squirrel
    Joined: Sep 23, 2004
    Posts: 48,278

    squirrel
    Member

    The valve tip shown is not worn that I can see. It just looks like the engine was overhauled, and got a valve job. The tips were refinished, but they didn't add more chamfer, and didn't replace the rockers.

    I've seen mushroomed valve tips, that have sharp edges and lots of wear...this isn't one of those.
     
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  12. gimpyshotrods
    Joined: May 20, 2009
    Posts: 18,004

    gimpyshotrods
    ALLIANCE MEMBER

    If you did mix up the lifters, etc, as has been mentioned, you might wipe out the cam, shortly.

    If you did, a nice, hydraulic lifter cam, that is compatible with your stock springs, with lifters is a tick over $200 US. and rockers are about $68 US.

    https://www.speedwaymotors.com/COMP...yd-Camshaft-Kit-Chevy-194-230-250,223473.html

    https://www.speedwaymotors.com/COMP...cker-Arms-Non-roller-3-8-Stud-Set,217715.html

    You'd have the assurance of a fresh cam (as long as you do the break in properly), and more power, too!
     
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  13. Century
    Joined: May 28, 2009
    Posts: 176

    Century
    Member

    The lifters, push rods, and rockers all went back in as they came out. I made sure to keep track of them.

    I guess I'll throw in a set of rockers, followed by a set of lifters if the ticking doesn't go away. The lifters are new, but you never know.

    I did notice that they aren't all the same. Some have a groove at the bottom, where others are smooth.

    upload_2020-4-11_14-27-19.png

    From the internet:

    with groove
    upload_2020-4-11_14-28-0.png
    without groove
    upload_2020-4-11_14-29-25.png
     

    Attached Files:

  14. squirrel
    Joined: Sep 23, 2004
    Posts: 48,278

    squirrel
    Member

    The different ways the build lifters doesn't matter, but the fact that they are not a matched set bothers me. Strange stuff going on with that engine.

    Hopefully it will last...
     
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  15. Century
    Joined: May 28, 2009
    Posts: 176

    Century
    Member

    The Melling JB817 lifter ad states "Second Design Without Machined Line", so I assume there are two versions. It's possible that the engine builder bought 12 and received a mixed set.
     
  16. Century
    Joined: May 28, 2009
    Posts: 176

    Century
    Member

    Thanks for your thoughts on this. I didn't consider that they may have refinished the original valves. That would explain why there's a bit less meat on them.
     
  17. 56sedandelivery
    Joined: Nov 21, 2006
    Posts: 6,695

    56sedandelivery
    ALLIANCE MEMBER

    I'm looking at the valve stem "Keeper" on the one photo; just does't look right to me. It's kicked off on the one side, or maybe it's the oil causing a reflection? I'm thinking you overloaded the lifters on the cam, and now the cam is going flat; a new cam, lifters, and related parts are in your future. What do the lobes look like? I am Butch/56sedandelivery.
     
  18. Century
    Joined: May 28, 2009
    Posts: 176

    Century
    Member

    To clarify, I did not run the engine after tightening down the rockers, so I doubt camshaft damage occurred. I adjusted them correctly after realizing my mistake. I pulled the lifters yesterday - they are not collapsed.

    Regarding the keepers, it's probably just the picture. Here are a few more. The first picture is of a different set of valves.

    valve train inspection 5.jpg valve train inspection 6.jpg
     
    Last edited: Apr 11, 2020

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