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Discussion Starter #1
Okay, I have numerous posts on my current string of bad luck, so here is another chapter. I had a bent pushrod on the #6 Intake, when I looked closer, I noticed that the spring was still compressed even though the rocker was removed. Is this what they refer to as coil binding or a stuck valve?

What should I do from here? Am I going to have to take the head off. Can anyone tell me why this happened and how to prevent it? Any information would be great!!
 

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sounds like you have a bent valve i havent seeen your earlier post

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Troy Miller
Whiteford,Maryland
70 Nova
72 Nova
66 Chevelle
 

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what are your motor details?

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Troy Miller
Whiteford,Maryland
70 Nova
72 Nova
66 Chevelle
 

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Discussion Starter #4
350 SBC, .454 lift cam, Z-28 springs, Holley 600cfm. New pushrods, rockers. I used the old valves.
 

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Discussion Starter #5
I took the head off and the valve was definately stuck. I had to bang on it pretty good to get it out. Believe it or not, the valve was not bent!! The stem was messed up though, it looked like it there was some metal to metal grinding because it gouged up pretty bad. Any idea what the problem is? Looks like I will need a new valve guide
 

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Boldly procrastrinating
66 El Camino 57 Chevy pickup 2004 Tahoe
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better have a look at the other valves while you've got it apart. What kind of lube was used for assembly? Did you do the assembly or did a shop do it?

Tom
 
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Sounds like the valve guide dried out or was to small. I don't know if you had the heads redone, but you need to make sure you have enough stem to guide clearance, more on the exhaust than the intake.

The damage on the valve stem means the guide is junk.



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Wally
Gold #67
67 Malibu "Small Block"
90 SS454
71 Malibu "Small Block"
93 torch red vette
 

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1Quik7D, sometimes the way to break a string of bad luck is to step back and do something totally different.

Pull both heads. Dissassemble completely using a valve tray or egg cartons to keep everything numbered and in order. Have bronze inserts put in. The studs pinned or tapped for screwins if you havn;t already. Once the guides are in you can fit the valves. Check the valve stems carefully for signs of wear. Replace all that are marginal. Lap 'em in and go.

I'm assuming this is not your daily driver and that you have a valve spring compressor.
 

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Not sure I agree with some earlier posts re: tight guides. From what I read, it sounds like the problem started with loose guides. You say you've put in a new .454 lift cam, new Z-28 springs, new pushrods,and new rockers, but reused old valves. did you check stem to guide clearance? I bet if you checked some of the others, they would be loose. I'm thinking that the higher lift cam, together with new springs and rockers, started pushing your valves sideways, accelerating guide wear. Betcha that was what trashed the valve.(my .02, you get what you pay for
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At any rate, the solution is the same, have new guides installed, replace any valves that are marginal, and regrind the seats. Check the valvetrain geometry when fully assembled, the rocker should be nearly centered(height-wise,tip to tip), with the pushrod side slightly lower. Cycle the motor thru at least twice to ckeck for coil bind and excessive angles/binding in the valvetrain. Also, don't forget about recommended spring pressures for your cam and installed height of springs.
Bryan

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'65 Malibu frame-off project(slow going!)
'70 C-20 Longhorn p/u (daily driver)
 
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You know what would be nice, when the problem is fixed and the cause identified if it could be posted. Nothing like trying to hit a moving target.

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Wally
Gold #67
67 Malibu "Small Block"
90 SS454
71 Malibu "Small Block"
93 torch red vette
 
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