battery drain

[siteunseen]

And the lubrication the machinest use isn't made to sit up. I think that's what happened to mine when I replied "sticky". I bought a head that was never picked up by the owner and although it was wrapped with poly and carboard on the valve end it was still tight or "sticky". I ran the oil pump with a drill on LOW speed and thought I had it worked out. Nope, lash pad came off on the first break-in drive.

There's no telling what caused that valve to stick but it did. I'll get in trouble for this but if the $100 headbolts just have one torque I'd reuse them.

You should find all the pieces if your gonna do it yourself. The valve keepers especially, there are small

[siteunseen]

EDIT: they could be oem Nissan? I was looking around and the colors are close.

Those are Fel Pro valve stem seals too. You'll need one but probably have to buy a set. I'll guess $15 from a chain store?

Edited November 23, 2021 by siteunseen

[Patcon]

All kinds of possibilities:

The valve could have gotten sticky

The valve lock might not have been all the way in

Could have just been a fluke

I would have real hope if the spark plug wasn't trashed. The valve might be bent but shouldn't be cost prohibitive to get corrected

[siteunseen]

A Harbor Freight boroscope thats images through your phone or "a real computer" like  @Zed Head capabilities of his you can stick it down the spark plug hole and give it a look. If that valve moves freely you may get lucky and not have separate the head?

[Jeff G 78]

45 minutes ago, siteunseen said:

A Harbor Freight boroscope thats images through your phone or "a real computer" like  @Zed Head capabilities of his you can stick it down the spark plug hole and give it a look. If that valve moves freely you may get lucky and not have separate the head?

Any Amazon wifi or bluetooth endoscope will work.  They are about $35 and most have a mirror attachment that allows you to see the top of the chamber.  I have the Depstech one and it works fine, though battery life on mine isn't great.  I just use an external battery so I don't have to worry if it's charged when I want to use it a few times per year.

[Zed Head]

2 hours ago, Dolfinz said:

few hundred to a friends son who helped me put it the rest of the way back together.

Get this guy back on it.  He probably has the tools, maybe, or can help you figure things out.  

And, big picture, your grandson might get more out of completing your project than just driving it.  Who knows.

I see potential surface rust plus dry seals here...

3 hours ago, Dolfinz said:

4 years ago it was a freshly rebuilt head I bought from Z Car Source here in Phoenix.  It sat in my garage for 3 years

But don't see the need to pull the engine.

3 hours ago, Dolfinz said:

considering this happened it's probably in my best interest to pull it and and have it inspected and repaired. 

 

[Dolfinz]

First off, regarding my Grandson he's 8.  A little out of his attention span at this point.  As for what may have caused it I have an idea I'd like to throw out.  I don't remember the rockers being so noisy.  When it was running it almost sounded like a diesel.  Could it have been an oil pressure problem that made the rockers so noisy?  And caused it?  Without an oil pressure gauge I have no idea what the pressure was.  When putting the engine back together I replaced most everything including the oil pump.  Are the rockers noisier than I remember?  The engine isn't leaking any oil and the dip stick says full so I don't know why the oil pressure might be low.  Any ideas?

I think before I pull the head I'll get the scope and see what I can see first.  But then, depending on what I find I'm pulling the dash and getting the gauges working.  I'm certain for some reason none of them are getting their positive feed as my understanding from the wiring diagram is the sensors all route their connection from the gauge to ground.  They were all working prior to my rebuilding the motor.

Just to clarify, If I get the scope and see no damage odds are the valve is still bent right?  Wouldn't this still require pulling the head to repair?  However, if the valve doesn't appear to be bent or damaged then simply replacing the damaged components for this cylinder above the springs might result in the easiest solution?  I appreciate all the ideas and advice but trying to determine a course of action is difficult.  I really hate to dismantle the engine again.

[Barefootdan]

11 minutes ago, Dolfinz said:

If I get the scope and see no damage odds are the valve is still bent right?

Hard to say just from a visual. If the valve was really sticky I could see it being pushed up and sticking up without bending. You'll need to get a hold of the valve itself to see if it spins and travels freely or not.

11 minutes ago, Dolfinz said:

Wouldn't this still require pulling the head to repair? 

Yes

12 minutes ago, Dolfinz said:

However, if the valve doesn't appear to be bent or damaged then simply replacing the damaged components for this cylinder above the springs might result in the easiest solution? 

If the valve is not bent and the cylinder is okay then yea you could get away with new clips and retainer if they arent damaged. Although, I'm not sure how to go about replacing the stem seal. Someone with more knowledge can chime in if it is possible to do so with the valve installed.

[pogden]

@Dolfinz, I have a boroscope, some extra unused valve stem seals that I'm hopefully never going to use, and the right size rope for filling the cylinder (if it comes to that). I'm in North Phoenix (~Tatum and Deer Valley), will PM you my phone number and we can talk. I'm about 10% as knowledgeable as the other guys who have been helping out, but I'm local and happy to help if I can. 

Word of warning: I'm not a Z whisperer, though maybe someday ...  Today, I did my first oil change on my own rebuilt L28, re-torqued the head bolts, and adjusted the valve lash. And now it idles and runs like crap. I'm hoping that I just don't yet have the "feel" for my feeler gauge and that I just got a couple of intake valves a little tight. The ups and downs of Z-itis. 

[Patcon]

I agree. You need to try to move the valve by hand, like Jeff and others recommended. If it moves freely I would reassemble it and run a compression test. If all the numbers look reasonable,  run it. After verifying oil flow and valve lash!

Pogden's help would probably be good.

Did you check valve lash before startup?

Did you verify oil flow at the rockers before startup?

[Dolfinz]

I will try reaching out to Pogden but I have 2 questions.  How do you check valve lash and how do you verify oil flow at rockers before startup?

[SteveJ]

31 minutes ago, Dolfinz said:

I will try reaching out to Pogden but I have 2 questions.  How do you check valve lash and how do you verify oil flow at rockers before startup?

You check valve lash with a feeler gauge, but it requires you to turn the engine. I wouldn't worry about that until you address the issue with the valve that lost its keeper.

To verify oil flow, what I like to do is fill a oil can with 10w30 or your favorite flavor. Take the coil wire off the distributor. Hook up a remote to the starter. Make sure the car is out of gear. Take off the valve cover. Put a generous amount of oil on each cam lobe so there is some initial lubrication for each rocker. Trigger the remote starter and look for oil to come out of the spray bar.