Spring/Keeper interference with Rocker

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Bobzilla said:
In the very first picture, closely inspect the tip of the exhaust valve on the far side of the picture. Maybe post a better/clearer picture of it, if it's questionable. The tip appears excessively or unusually worn, but may be the glare in the picture.
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Does not look bad in person, not worn unevenly / poorly.

IMG_20200325_170741587.jpg
 
Do I see I little sign of contact here?
Right in the corner of the relief cut.

Even if it is, it looks so light I doubt you’d hear it.

4308D58D-8EA9-4519-8549-2B37A9053D73.png
 
did someone put longer valves in heads/ if they came off a one ton truck they could have had rotators on both intake and exhaust valves
they sit lower with 4 grouve keepers on both valves
with everything mismatched
 
Definitely looks much better in the new picture looking straight down on it.
Any chance at all the exhaust manifold is leaking? I see those steel gaskets and they look like they been on there a while. If nothing was found in the valve train, and it still runs well, maybe could it be a pesky exhaust leak?
 
The valve spring retainers are incorrect. The factory 340 ones have a bevel on the top and they taper down to .080'' thickness at the outer edge. Your retainers don't center the springs very well. It could be the sharp edges of the springs that are hitting the rockers. Someone already mentioned valve recession.
 
teringer said:
did someone put longer valves in heads/ if they came off a one ton truck they could have had rotators on both intake and exhaust valves
they sit lower with 4 grouve keepers on both valves
with everything mismatched
Click to expand...

To the best of my knowledge, these are factory heads from this motor, from this car. valvetrain was redone by a shop 15 years ago here in MI. I would assume if there were longer valves this would have been an issue from day one.

As I went through it yesterday, II cleaned up the rockers very well, and did not see any 'new' interference marks; they look like hand grinds, and have oxidized over. I'm not sure it's in the valvetrain any longer. I see no witness marks on any of the retainers/springs either.
 
Bobzilla said:
Definitely looks much better in the new picture looking straight down on it.
Any chance at all the exhaust manifold is leaking? I see those steel gaskets and they look like they been on there a while. If nothing was found in the valve train, and it still runs well, maybe could it be a pesky exhaust leak?
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This is my next check; doing that today. I'm hopeful considering everything in the valvetrain checked out. (with the exception of small retainers)
 
pt70 said:
The valve spring retainers are incorrect. The factory 340 ones have a bevel on the top and they taper down to .080'' thickness at the outer edge. Your retainers don't center the springs very well. It could be the sharp edges of the springs that are hitting the rockers. Someone already mentioned valve recession.
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I agree 100% that the retainers do NOT look correct. This is something I will definitely resolve, but I would like to find this noise first before part swapping. I cannot find any witness marks of spring/retainer/rocker interference. Initially, while covered in oil, it appeared as if that was the issue. upon cleaning, there are no new wear marks.
 
The retainers look stock and 340's came with factory "clearanced" rocker arms. If you run 340 valve springs, larger diameter, you need to check clearance between the rocker and spring/retainer. What you have looks OK to me. Your cam is probably loosing a lobe.
 
Compare the push rod lengths and can you post a picture with the rockers in the installed position -relaxed and a picture from the side

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66fs said:
The retainers look stock and 340's came with factory "clearanced" rocker arms. If you run 340 valve springs, larger diameter, you need to check clearance between the rocker and spring/retainer. What you have looks OK to me. Your cam is probably loosing a lobe.
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I'll be checking the int/ex valve lift with a dial indicator later this afternoon; this'll tell us whats going on with the cam... crossing my fingers...
 
69FBCuda said:
Compare the push rod lengths and can you post a picture with the rockers in the installed position -relaxed and a picture from the side

View attachment 1715494210
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I'll do that shortly; I have some other items to get wrapped up first.

On a side note, all push rods are the same PN - assumed to be the same lengths.

Again, I am not seeing any 'new' interference with the rocker / retainer / spring. After cleaning them up, it was all old, oxidized hand grind marks.

Thanks guys
 
The contact point of these stock rockers 'walks' forward and back across the tip on each cycle. So with valve closed, the contact should be on the shaft side of the tip center.
So this looks either normal or the valve is a tiny bit lower than normal.

Maybe I missed it OP..... did you get spring OD, and spring height from top of spring to bottom of spring cup?
 
nm9stheham said:
The contact point of these stock rockers 'walks' forward and back across the tip on each cycle. So with valve closed, the contact should be on the shaft side of the tip center.
So this looks either normal or the valve is a tiny bit lower than normal.

Maybe I missed it OP..... did you get spring OD, and spring height from top of spring to bottom of spring cup?
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I did not get spring OD / height yet; can find my damn mic's. Working on that
 
That sounds like a collapsed/stuck lifter.
 
69FBCuda said:
That sounds like a collapsed/stuck lifter.
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I just put a new set of lifters in 3 mo ago because of this sound. I understand that one could be bad out of a bunch, but it's the same side, same area. The odds go way down with that. Essentially NOTHING changed when installing new lifters.

Thanks,
 
Have you tried cranking it with the cover off, I'v done this while recording to check lifter movement.
 
69FBCuda said:
Have you tried cranking it with the cover off, I'v done this while recording to check lifter movement.
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Oh yes, even ran it with the cover off, made a mess, but it told me nothing. Everything is cycling as it should. no 'de-primed' lifters, meaning I cannot push them in with the rocker when valves are closed. Considering the oiling at the lifters, I assume it is not a stuck lifter, as I would not get any oil to the rocker arm, correct?
 
Lik said:
Oh yes, even ran it with the cover off, made a mess, but it told me nothing. Everything is cycling as it should. no 'de-primed' lifters, meaning I cannot push them in with the rocker when valves are closed. Considering the oiling at the lifters, I assume it is not a stuck lifter, as I would not get any oil to the rocker arm, correct?
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The rockers on these LA engines are oiled from the shafts, which get oiled through the block. (Magnums oil through the lifters and pushrods, but not LA's.) But it sure looks like plen-tee of oil.

If you are pushing on all the rockers to try to find a soft lifter, or other loose valvetrain part, you have to tun the engine for a few minutes to get oil in the lifters, stop the engine, and rotate the engine several times by hand and push on each rocker when its lifter is in the 'valve closed' position. (I.e., each lifter is on its cam lobe's base circle.) If you test like that, and all are hard, then you are good.

I got no audio on the video, and the video did not show the actual sound waves in the air.....
 
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