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[URL=http://s104.photobucket.com/user/thegillybilly/media/MashedValve.jpg.html][IMG]http://i104.photobucket.com/albums/m198/thegillybilly/MashedValve.jpg[/IMG][/URL]
1999 Silverado 5.3 Vortec 125k mi. It started making a ticking noise from the head. I pulled the valve cover off and found that the top of the valve and the retainer were mashed (see pic). I have a spare head so I figured I would just put that on instead of replacing the valve and retainer. My worry is that it will happen again to the new head. The lifters seemed clean but I’m not sure what too look for on them. They are soaking in diesel at the moment. What could have caused this and how can I make sure it doesn’t happen to the new head?
Thanks for the help.
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Here’s the rocker arm. It’s not too bad but I wouldn’t reuse it.
[URL=http://s104.photobucket.com/user/thegillybilly/media/DSCN0653.jpg.html][IMG]http://i104.photobucket.com/albums/m198/thegillybilly/DSCN0653.jpg[/IMG][/URL]
[URL=http://s104.photobucket.com/user/thegillybilly/media/DSCN0656.jpg.html][IMG]http://i104.photobucket.com/albums/m198/thegillybilly/DSCN0656.jpg[/IMG][/URL]If you look at the 2 push rods in the pic, one is missing the rounded ball at the tip, while the one on the left looks intact. I would be concerned with plugged oil passage also. Rocker looks like it may have a chip missing. Has the oil been changed regularly? (3-5 thousand miles). The 5.3 is usually good for 200k plus with no major issues.
Thanks for the replies. I checked the pushrods and none of them are plugged. I also rolled them on a pane of glass and they all seem straight. Visually they all look fine. Here is a better picture of the top end of the pushrods:[URL=http://s104.photobucket.com/user/thegillybilly/media/DSCN0658.jpg.html][IMG]http://i104.photobucket.com/albums/m198/thegillybilly/DSCN0658.jpg[/IMG][/URL]
I don’t know the history of the engine because I haven’t had it very long. I did an oil change about 3000mi ago with full synthetic. The engine doesn’t look like it has been abused to me but I’m just a novice. Any other ideas? Could it be a problem with the lifter?
That is an unusual thing to happen in todays engines. A soft metal defect from new or lack of oil would be my guess. You’re lucky you found it when you did as it would have soon become catastrophic.
If you replace the cylinder head I would also replace the pushrod, rocker arm and lifter for that cylinder.
2 guesses.
1. normal GM cheap metal (they had system of incentives introduced for years for those who provides them with cheaper parts)
2. bent valve stem. As the result, you had excessive resistance coming from valve that cause damage. There is much more damage to the valve stem than there is to pushrod.
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