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502 Mag engine noise with video.

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Old 04-22-2017, 08:49 AM
  #31
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Got the video to work. Sound is in the valve train - not bottom end. Bolt-down (non adjustable) rockers can only "gain" clearance by the following:
Lost a cam lobe
Collapsed lifter
Bent pushrod
Damaged roller rocker (which you don't have).

Other sources for valve train noise are
Sticking/bent valve
Broken spring or damper
Loose valve seat

Isolate the problem cylinder by removing one rocker at a time. You'll need to keep finger pressure on the push rod to keep the lifter from popping out if its bore - unless you run stock GM Dog bone roller lifters which are trapped by the orientation plate. I can't recall if your motor is a roller or not.

If you run dog bones you can remove as many as you want.
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Old 04-22-2017, 08:50 AM
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I'd try another oil filter first,,doesn't seem like alot of oil up on the top end.
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Old 04-23-2017, 05:57 PM
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Wish I had better news. Dropped valve seat on the number 7 exhaust valve.






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Old 04-23-2017, 06:15 PM
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Quote:
Originally Posted by RGPIII View Post
Wish I had better news. Dropped valve seat on the number 7 exhaust valve.






That blows! At least you caught it early. Still plenty of season to go!
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Old 04-23-2017, 06:57 PM
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That blows but you got off relatively lightly. My engine was destroyed when my valve seat departed.
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Old 04-23-2017, 06:59 PM
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What does other side look like? If no worse than this, you need a pair of heads. 990's are easy to find. I only have 1 spare set, but I know of a guy with some. Hell, half the people on OSO know where to find a set of these...oh, that is both sides...edit again. I was thinking of diff thread with guy with low comp in 7 and 8.

Last edited by dereknkathy; 04-23-2017 at 07:37 PM.
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Old 04-23-2017, 07:00 PM
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At least it looks like the piston got ugly, but not killed.
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Old 04-23-2017, 07:52 PM
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I would be jumping right on a rebuild if I hadn't already spent 21,000 this off season. she's gonna sit for a while before I spend money on a rebuild most likely.
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Old 04-23-2017, 07:56 PM
  #39
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That's a bummer, spend that kind of coin and not have it last any longer then this.
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Old 04-24-2017, 05:40 AM
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put heads on and do a compression test.
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