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Broken rocker messed up top of valve what to do?

Discussion in 'The Garage' started by VisionxOrb, Nov 13, 2003.

  1. VisionxOrb

    VisionxOrb 1/2 ton status

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    Ok I was driving home from college today, getting on the freeway and BAM, rocker broke, and when I got it back to my house and pulled the valve cover notice the top of the valve was different then the rest, heres a pick of the with the top of messed up valve and another near it thats normal (warning its webshots) [image]http://community.webshots.com/photo/66262447/99906860gkFHMv[/image][image]http://community.webshots.com/photo/66262447/100045986imXNpt[/image]

    The question is now, What do I do since I guess I cant just replace the rocker for the time being. Thanks in advance for any thoughts
     
  2. 75-K5

    75-K5 3/4 ton status

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  3. MOABDADC22

    MOABDADC22 1/2 ton status

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    Do not drive it!!!!! It looks like (from what I can see in the pic anyhow) the keeper has worked loose and by the grace of GOD.....you have not dropped a valve yet .

    Pull the head and take the head to a machine shop and have the valve replaced. Or do it yourself and save a few bucks....
     
  4. Beast388

    Beast388 1/2 ton status

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    Ouch!
    It looks like you scrubbed off about 0.100" off the top of that valve stem. Not much you can do besides pulling the head and replacing that exhaust valve.

    If you try to run it like that, your rocker geometry will be way off and you will risk popping the keepers off and dropping that valve into the cylinder. /forums/images/graemlins/eek.gif /forums/images/graemlins/eek.gif
     
  5. fortcollinsram

    fortcollinsram 1/2 ton status

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    Yeah you mushroomed the piss outa that valve tip. IMHO, I think this is the time to take a few days and pull the heads, drop them off at a good shop, and get the heads cleaned and replace and valves that are toast and have a decent valve job done on the heads. That is ofcoure if the lowerend is SOLID (maybe do a comp. check to make sure it is worth the time). A valve job on my BBC heads was pretty cheap. It was like $340 for cleaning, shave .015" off, valve job, new guide and seals and reassembly...

    But you def. need to pull at least THAT head and replace the valve

    Chris
     
  6. grunt11b40x

    grunt11b40x 1/2 ton status

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    damn! the best thing to do is pull the head and replace it. a quick fix may be to get a self alianing rocker arm for a 97-98 vortec engine and see if it will hug the mushroomed valve head and keep the rocker running true. but this is a temp fix . if you have the time and or another ride pull the head. oh yea check the push rod too. good luck man. /forums/images/graemlins/thumb.gif
     
  7. dyeager535

    dyeager535 1 ton status Premium Member

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    [ QUOTE ]
    a quick fix may be to get a self alianing rocker arm for a 97-98 vortec engine and see if it will hug the mushroomed valve head and keep the rocker running true. but this is a temp fix

    [/ QUOTE ]

    Just as a heads up, NEVER use a "guided" rocker on a setup not intended for it, and even more, not on THAT valve! The guides are EXCELLENT at removing the valve locks. Vortec valves (for instance) have the valve stem set up to keep the guides from getting anywhere near the locks. The shorter the valve stem end to lock distance, the worse the problem using guided rockers is going to be.

    If you don't know what a guided rocker is, it has two raised portions on the rocker tip, that sit on either side of the valve stem, to keep the rocker from moving side to side (using the valve stem for alignment), instead of guideplates or the pushrods hitting the block.
     
  8. VisionxOrb

    VisionxOrb 1/2 ton status

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    Well I guess I dont have much an option other than pulling the head so I guess thats what Im gonna do, thanks guys for the input.

    P.S. First time doing this, this ought to be fun /forums/images/graemlins/1zhelp.gif
     
  9. randknu

    randknu Registered Member

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    I have a 350 in my own 78 K5 and I can't really see what's wrong in the picture, The valves on the picture shows one intake (left) and one exhaust (right) valve, and they are different to begin with, the only bad thing in the picture is the pushrod, which looks like it has taken quite a beating.

    However it's hard to say at the angle from the picture that nothing is wrong with the ex-valve but as i said take a look at another exhaust valve before doing a big job out of it.
    That pushrod should be changed anyway.

    I recently changed my valve seals and all of my valves looked like that...
     
  10. R72K5

    R72K5 Banned

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    being as mushroomed as the end of the valve stem is, youll probably have to grind off around it to allow it to be pulled through the guide,

    quick fix would be to remove head and get cheap sprign compressor tool and replace the valve and rocker and be done, or even better would be to have new guide installed also,

    but either way head has to go to machine shop to have seat ground and new valve ground, so...

    depending on mileage on heads you might need to have new guide installed anyways.

    ive seen this happen once or twice, i had a 79 k10 that the 350 mushroomed the heck out of a stem just like in the pic, also i have had a couple other '70's era 350 engines that had pushrod go clean through rocker arm.

    just happens, never know when or why really.
    mileage and wear and thats about it

    maybe even too loose of rocker adjustment even, you might want to check that when you get head reinstalled after the valve repair is done
     
  11. unick

    unick 1/2 ton status

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    Get some new aluminum heads if you have the money. Dont just fix it make it better.


    Nick
     
  12. fortcollinsram

    fortcollinsram 1/2 ton status

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    What kinda budget are you on? You could probably get buy and get it fixed for less than $100 iff you take the head off..I still think the best way to go is to pull both heads at once and get them both worked over a bit. The best advie I have for pulling a head IN the truck is get as much crap out as you can. Pulling the quater panel with make things A LOT easier.

    Also drain the coolant BEFORE taking the intake and head off. And get some decent intake and head gaskets. Other than that it is really easy, just time consuming...

    Chris
     
  13. fortcollinsram

    fortcollinsram 1/2 ton status

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    Another thing that makes me curious is WHY is the valve tip mushroomed like that and WHY did the rocker break? Did you have the lash set too tight Do you have a Non-Stock cam? That rocker was obviously binding somehow to cause the tip to mushroom and the rocker to break...
     
  14. VisionxOrb

    VisionxOrb 1/2 ton status

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    [ QUOTE ]
    Get some new aluminum heads if you have the money. Dont just fix it make it better.


    Nick

    [/ QUOTE ]

    This Id love to do, im always " it broke!!! time to upgrade " although right now im out of the job so my budget is almost non existant ( family gonna help with the repair bill ) Ive just finished pulling the head, took about 3 hours. The motor is relitivly low miles about 15k. I was debating taking off the other head and having them done to use screw in studs and guide plates so I could use roller rockers and avoid this problem again, but these heads are your regular smog head, dont think its worth putting any work into becuase there potential is very limited.
     
  15. VisionxOrb

    VisionxOrb 1/2 ton status

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    [ QUOTE ]
    Another thing that makes me curious is WHY is the valve tip mushroomed like that and WHY did the rocker break? Did you have the lash set too tight Do you have a Non-Stock cam? That rocker was obviously binding somehow to cause the tip to mushroom and the rocker to break...

    [/ QUOTE ]

    Well the cam isnt stock but its mild, 204* at .050 , thats all I can remember about it. I dont have the particulars because well long story. Dont suppose any one remembers the story a little over a year ago when I was At fort bragg NC and my mom was bring the truck back to my and broke down in Blyth california where the crook mechanic took her for a ride and had her put in a crummy rebuild and took out my 383, w/ my fat crane 276/284 powermax and my comp pro magnum roller rockers, basterd mechanic using all my cool parts.
     
  16. dyeager535

    dyeager535 1 ton status Premium Member

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    Just another aside, but if one valve went, and it was from age, the others PROBABLY aren't far behind, unless you know the cause of this, and know it was cylinder specific.

    Bought an Olds motor out of the wrecking yard, ran it for two years, and pulled it to rebuild. All the valve stems were mushroomed somewhat, but you couldn't tell it with the valves in the head. Seems to be pretty common of the valves, no fault of their own, just heat, age and fatigue.

    If the valves weren't replaced when the motor was, I'd seriously consider replacing all of them.
     
  17. VisionxOrb

    VisionxOrb 1/2 ton status

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    im pretty sure the valves were done when the motor was because well, these aent my heads, I had world SRs, these are from the rebuild place. but also I took another photo from a different angle [image]http://community.webshots.com/photo/66262447/100045986imXNpt[/image]
     
  18. mdm365

    mdm365 1/2 ton status

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    moabdad is correct the keepers are gone but....were did they go??? /forums/images/graemlins/eek.gif mike
     
  19. VisionxOrb

    VisionxOrb 1/2 ton status

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    [ QUOTE ]
    moabdad is correct the keepers are gone but....were did they go??? /forums/images/graemlins/eek.gif mike

    [/ QUOTE ]

    UHHH ( crossing fingers ) oil pan /forums/images/graemlins/grin.gif /forums/images/graemlins/confused.gif /forums/images/graemlins/1zhelp.gif
     
  20. 75-K5

    75-K5 3/4 ton status

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    Can't remote link to webshots /forums/images/graemlins/thumb.gif

    [​IMG]
     

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