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2012 Chevrolet Caprice PPV

I saw one where a guy freed them with a rod he shoves down the pushrod hole and hits it with a hammer.


Seems to me like it would just get stuck again, since nothing has changed regarding why the lifter became stuck in the first place.
 
regal403 said:
I saw one where a guy freed them with a rod he shoves down the pushrod hole and hits it with a hammer.


Seems to me like it would just get stuck again, since nothing has changed regarding why the lifter became stuck in the first place.
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The dumb spring on the Lifter is a possibility.
 
If it's stuck due to some debris or sludge, dislodging it will hopefully land it in the oil filter. If it's stuck due to wear or damage, it will stick again.
 
I've heard the BG brand EPR stuff is supposed to clean them out. I just pour in a quart of atf then drive it around a bit before an oil change.
 
Chevy305 said:
Time to pull a valve cover and see if all rockers are intact and tight.
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#6 intake rocker trunnion is shelled out 1000018942.jpg

1000018945.jpg1000018947.jpg

The tip is buggered up too
1000018948.jpg

Is the end of the valve stem ok?
1000018950.jpg

Here's one from #4 with a good rocker for comparison.
1000018949.jpg

Also I think the pushrod is very slightly bent.

Advice?
 
You're asking if the tip of the valve can be polished? Maybe, but the question is "why did this happen?". I think people will point to a stuck lifter, especially if it's AFM parts. That could cause damage to the cam.
 
It has an aftermarket cam and the AFM/DOD has been deleted and tuned out from what I understand. How do I go about troubleshooting a stuck lifter? Stick the pushrod back in and turn over the motor real slow to look for movement up and down?
 
We used to buff off the tips of valves all the time when overhauling diesel engines at the dealership. Just used a die grinder with a brown Roloc disc but you could probably do it by had with emery cloth.
 
So you're theorizing that the rocker went first and seized up and the rod bent breaking it free?
 
Blue85 said:
So you're theorizing that the rocker went first and seized up and the rod bent breaking it free?
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That's my current thought, yes. But could the rocker failure have been caused by a stuck lifter?
 
I can get a factory replacement rocker pretty cheap it looks like. I just need someone to tell me what to do next.

Should I simply put in a new pushrod and rocker arm, change the oil and filter and let it rip? Or will that potentially cause further damage if in fact I have a bad lifter?

I could just replace the entire valve train as peace of mind, but I don't want to light up the parts cannon just yet.
 
On a mechanical AFM delete, what prevents the lifters from rotating? Is it just factory parts from a non-AFM engine?
 
Those rocker failures are documented on the G8 forums. Seems to me there were some kits that replaced the needles w/ bushings. Also, Yella terra and Harland comes to mind as being reliable.
 
I put a new rocker on and the sound went away. However, I hear a slight ticking on the driver's side. I popped the valve cover and nothing is obviously failing, but there is side play on all the rockers, some more than others.
I ordered an upgraded trunnion kit from Summit, which is supposed to be better than stock for higher lift cams. I figured if I had 1 fail, others could fail too. Mine may or may not be original, but they are the stock design.
Rocker trunnion failure is not uncommon, but the debate on whether to put new trunnions with needle bearings (like stock) or a bronze bushing was inconclusive to me. I went with needle bearing style units with upgraded materials over stock. They also have C-clip retainers and allow for more valve lift than stock.
Should be here in a few days.
 
So I've had this little noise that's been getting worse. Changed the oil in June or July probably, saw some evidence of glitter. Fresh oil, got quieter.

More recently I popped the valve covers and looked around, found one of my new rocker trunnion clips had broken, so I replaced it. 20251001_191001.jpg20251001_191009.jpg

Put a new C-clip on it, noise was basically the same. Now it's getting worse, more like a ticking than a rolling, mechanical sewing machine noise.

Drained the oil and cut apart the filter. There's gold glitter flakes in it, super cool.


Here's what it sounds like.

How cooked am I?
1. Throw some engine honey down the yap and run it until she blows
2. Rebuild or replace the engine
3. Part it out and sell it as a roller

Please give any and all advice. I'll be back to dailying the Jimmy into further notice... Again.
 
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