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Discussion Starter · #1 ·
I told the builder I have excessive valve noise! Notice the grind marks on the valve stem. This rocker had to be broken from day one. Can't believe the keepers didn't pop out. Drove it 8000 miles like this. Wish I had pulled the covers before now.

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Looking at it, my assumtion was that it would bow the spring a little (since it's only pushing on the very edge of the retainer and only a small amount) and the valve likely wouldn't open. If it was opening, it was a very little. You'll probably feel like you've got a ton more power when you get it fixed, haha.
 

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Discussion Starter · #5 ·
I hope so! Maybe it will idle a bit smoother as well. Mostly grateful the keepers didn't let go. The builder agreed to install new trunion, rocker, retainer and keepers. Hoping the lands on the valve stem aren't 'goobed up' (technical term). I posted to see how common is a broken rocker arm? Am 66, been working on mowners, motorcycles and cars since I was 14q. Never saw a rocker arm that just broke for no obvious reason.
 

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You are so lucky that the rocker hitting just the edge of the retainer didn’t release the locks and drop the valve into the engine.
 

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Discussion Starter · #8 ·
Update: replaced just the rocker/trunion and it is quiet like a new engine. First time since the rebuild 2 years ago it sounded normal. That was a damn good feeling. As far as the pieces of the broken rocker arm, they must have made their way to the pan long ago. So, still p/o'd at the builder, even though he gave me a replacement rocker assembly. He says he will replace the retainer and keepers... in 3 weeks or so.
Funny, when my new 'friends' at the Valdosta Extravaganza dragged some random dude over to listen to my mess - then he just threw his hands up and walked away - that convinced me to tear into it myself.
The G8board is a great forum. Thanks....
 

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Good deal. Neither here nor there albeit did the random guy walk away in disgust or confusion? G8 board members collectively posses a wide array of knowledge and information. Fortunately, the vast majority don't mind lending a helping hand here and there.
 
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Discussion Starter · #10 ·
He was told about the rebuild as he came over. I read his reaction to mean: 'sorry, bud, you have a real problem - beyond help here.'
And I already knew that, just procrastinating to learn and perform rod measurement on the thing. Hard to even guess it was a broken rocker. And the lifter tapping sounded like it was on both sides.
 

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My G8 didn't suffer a broken lifter, per SE, but it did have a valve spring break in half, which I initially thought was a collapsed lifter, so I had a full DoD delete and cam installed. I threw as much money as I could afford at the time into that rebuild, including new push rods, springs, oil pump, timing chain and rollers. After 4 years of daily driving, the car developed a tapping on a drive from northern California down to L.A.. That tapping turned to a knocking, then a banging along with a loud squeaking. I thought again it was a lifter failure. I found a great shop in Signal Hill that did the diagnosis and repairs... As it turned out, since I hadn't done the trunion upgrade during the cam replacement, one of the rocker trunions had let go. It was running like total crap, and I thought I was killing it with every minute I HAD to drive it to get off the hiway and onto a parking spot to get it towed to the repair shop. With a trunion kit install and an oil change, it was only a few hundred dollars and it's back to daily driving. BTW... the squeaking noise was coming from the belt drive... we initially thought the wobble of the harmonic balancer would necessitate a balancer replacement, but I changed out an aging tensioner and pulley and the squeak has disappeared. BTW... the valve spring break\cam replacement was at 102k miles, and the latest trunion failure was at 132k miles.
 
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