Maybe something bad...

[Xenn]

Long story short, my engine was making an intermittent ticking, opened it up to make sure a valve hadnt gone lose form an adjustment I did a bit back and realized my #5 valve spring was completely extended, as in, did not stop pressing against the rocker arm even when the rocker arm was completely "lose" so I brought the exhaust valve next to it all the way down then counted the turns to get it adjusted to the right level for the other one that I could not adjust. Adjusted the other one to that point, then set the good one to its correct position and threw it back together.

From my understanding of how the valves work, the only way that would happen with the spring is if the head of the valve broke off and has been eating my car all day, with the knowledge that the damage had been done already if that was the case, i turned my car back on and the ticking went away.

Anyone have any clue what is going on? the only thing i could think of would be the valve stem broke and the piston has been tapping the valve back in *shiver*. Anyone have a less painful guess than that?

[Zed Head]

Was the suspect valve on the base circle? You should read up a little on how to adjust valves. You might have just opened that valve up and are in the process of burning/warping it or it's so far open you've lost a cylinder (no compression).

The proper valve adjustment process is described in the Engine Tuneup chapter of the FSM. Your current method is way off.

[Xenn]

Ive done many vallve adjustments on that car, its been through a lot.

Speaking of which, at some point that engine had been in an accident and the rocker arm for that same valve was knocked off and it was drove for a little while like that before I fixed it, so that valve already has the potential for damage.

Yeah it was on the base circle, I go one step further than the chilton and have the cam lobes for each valve point up as I go, rather than setting the #1 up or down land adjusting 6 at a time like it says. .025m for intake .03 for exhaust, this is on an intake.

#5, intake for cyl 3, which also had an oily spark plug

And I set it like that because I got to that rocker, and the gauge wouldn't fit, so i started to loosen it to the correct position, it never got there, then i noticed the problem with the spring. I had no measurement to go off since I could not measure it correctly, so i set it as close as i could.

Is the only thing that limits the valve spring the valve is what im asking? If so mine is probably broken somewhere.

Edited March 19, 2013 by Xenn

[Darrel]

One other thought. What year and does it still have bronze seats?

[Xenn]

Its a 77 280z with the engine and transmission from a 79 280zx, the seats didnt look bronze but im not 100%

Also I could press down on the valve spring and it would go down fine but always came up higher than it should

Edited March 19, 2013 by Xenn

[Zed Head]

I've heard of the valve heads "mushrooming" or "tuliping", probably just before they break off. Valve seats also can wear down until all of your adjustment is gone, apparently.

Since you know what you're doing, you are probably thinking also that it might be best to fix that before the head breaks off and does more damage. Plus your "fix" doesn't really make sense. If you couldn't loosen the nut enough to get the valve to seat correctly with lash, there's no way to guesstimate a better spot by making it tighter. It needs to be looser.

A cylinder pressure check might show you something.

[Darrel]

Its a 77 280z with the engine and transmission from a 79 280zx, the seats didnt look bronze but im not 100%

Also I could press down on the valve spring and it would go down fine but always came up higher than it should

Have you had the head off before? These cars took regular fuel till at least '79. I pulled the head off a '79 620 pu l20b still had the bronze seats.

[Xenn]

I wouldn't say I know what Im doing, its more of someone mechanically inclined trying to restore a car worth restoring with minimal money and maximum will power. I haven't been formally taught, or worked on cars all my life, I work on my car, try to troubleshoot problems in a logical manner, fixing and replacing things as I go. Ive had this car for years, and do everything I can to keep it running/improving.

So no I'm not driving it if I think anything fell in the piston, , especally a big chunk of metal. My engine had been getting louder so i thought it was a rocker arm working lose, it had an dd intermittent ticking today that seemed to go away at different rpm's, i opened it up and found this.

Sorry if I sounded touchy about the valve adjustment, I did like 6 of them over the course of a couple weeks not that long ago when I thought I had a random lose valve before I realized it was my failing fuel injectors being obnoxiously loud

I thought you meant rocker arm seat, not valve seat, I have not yet taken the head off, the engine was mostly rebuilt right before I got it, so I dont know there.

Also if the valve head did come off, (and im planning on replacing the piston rings if i open it up) how scarred can the piston be before I have to replace it, I assume I would have to hone it out as well.

[Darrel]

Adjust the valves. If you have no adjustment on the valves then you will have to take the head off.

The valve head aka broken, your engine probably wouldn't be running right now. That is also a worse case scenario. Which is the worse thing you can do.

K.I.S.S.--- Keep It Simple Stupid.

There is some ticking which is normal in these engines, most of that comes from the injectors.

If there is no adjustment in the valves then chances are the seats have sunk or worn out, probably bronze seats.--pull head

Noisy, running bad, etc the bronze seat may have come loose. Bent valve, nicks in the piston, worse case.--- pull head

Noisy, running bad. Pull valve cover. If rocker arm and lash pad is off, put back on, adjust valves and run some 44k or seafoam. Possible sticking valve, 44k or seafoam may correct the problem.

[Xenn]

So sounds like pull head and hope for worn valve guide, the thing is i was able to do a correct valve adjustment not that long ago, i only thought I didn't fully tighten a locknut all the way down, it's when i went through, on the piston i knew had been running badly, that i found the valve spring...unrestrained? Not loose because the rocker arm against the cam holds it back.

its suddenness is what makes me think its a broken valve or valve stem, and the fact that it is the only thing i know of that holds the spring.

[Darrel]

Is the lash pad still on top? Take a pic of the valve in question. I am getting confused with your description.

[Xenn]

Also, if i end up going through the trouble of ripping the head off, what would you recommend doing while I had it open?