battery drain

[Barefootdan]

I'll be the first to admit not to jump to conclusions if the motor isnt running 🙂 As @Zed Head mentioned, I had a rocker arm come off and I immediately thought my newly rebuilt engine suffered a head gasket failure. Lets see whats under the valve cover first and work our way through it. I am also in Phoenix too! I just finished rebuilding my L28 so it is fresh in my mind 😄 

[siteunseen]

I'd just rebuilt one too and a lash pad fell of. Lots of noise but no damage. From what I remember the valve train is "sticky" after rebuilding and things need to commingle for the first few miles.

Don't throw in the towel! Speaking as a grandson nothing would mean more to me than my Grandad giving me his pride and joy. I got a bunch of fly fishing gear and a couple of guns but that's nothing compared to a Z car.

Hopefully it's something simple. Cliff

 

[Dolfinz]

I think I found the problem.  See attached picture.  Question now is how do I fix it?

[Zed Head]

Ouch.  That might be the disaster you feared.  Even the valve seal came off.  Odds are high that the valve hit the top of the piston.  Hard to imagine a scenario where it didn't.

Pull that spark plug and see what you find.

[Patcon]

Be very careful messing with that. The valve lock is gone. So if you take the pressure off the stem, the valve's gonna drop into the motor. Would be interesting to put air to the cylinder to hold the valve up. If it stays up and holds air pretty good. i would reassemble it and run a compression test. These engines are very tough. My first concern would be a bent valve stem

[Dolfinz]

So,

the impression I get from Patcon is that there may be a way to reassemble this without pulling the head off.  I understand that the valve may be bent but it would seem to make sense to try it before going to the trouble of tearing the engine apart.  Any additional thoughts or suggestions?  I've never personally worked on the head so I have no clue if this is possible.

[Zed Head]

2 hours ago, Dolfinz said:

the impression I get from Patcon is that there may be a way to reassemble this without pulling the head off. 

If you are super super lucky.  He's saying to find a way to hold the valve stem up so it doesn't drop in to the cylinder if the piston is down.  You could also rotate the engine to bring the picton up so that it will hold the valve up while you collect those parts that are scattered around.  Or you could remove the spark plug and fill the chamber with rope or tubing.  Many tricks.  Don't rotate the engine until you have a plan.

In the meantime - have you removed the spark plug yet?  If the electrodes are all smashed up that means there's been valve head damage and the head will have to come off.

You can also shine a light in to the hole to see if the piston is up.  You can learn a lot just by removing a spark plug.

[Dolfinz]

I did as you suggested.  I pulled the plug and the piston is up.  Not sure if it's all the way but I can see the piston head through the spark plug hole.  Also, there's no damage to the spark plug electrode.  Next steps?

[Zed Head]

You're in a zone where you have to use some of your own gut feel.  If you have a piece of tube that will fit tightly over the tip of the valve you could slip that over the valve tip so that you can hang on to it.  Remove that rocker arm and see if you can rest the valve on the piston top without dropping it all the way in.  Pull the valve up and spin it to see if it's bent.  

Really though, you're just assessing damage at this point.  Even if you want to put it back together you'll need a valve spring compressor.  If you don't have plans to do the work yourself you might be best off to have a pro look at it and give you an assessment.  A pro with a bore scope could take a look and tell you there's piston damage, maybe cylinder head damage.  Today's borescopes are inexpensive and powerful.  You could learn a lot without taking it apart.

If the valve head had been destroyed and come apart I'd expect the sparkplug to have been damaged as the pieces bounced around.  It seems like maybe the valve took one hit, got bent, got stuck up in the guide, and the noise was the rocker rattling off of the cam lobe as the engine kept running.  You're most likely going to have to remove the head, it's just a matter of how much you want to do before making that decision.

[Dolfinz]

I was really trying to have to avoid it but considering this happened it's probably in my best interest to pull it and and have it inspected and repaired.  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 until I was finally able to start putting the engine back together about a year ago.  I had taken the lower end to a machine shop and had it rebuilt; since it was apart, shortly prior.  All I can figure is that all the time the head sat is why this happened.  I really can't see that it needs to be rebuilt again unless there was some type of damage to the head due to what's happened.  Question will be where to take it to ensure this doesn't happen again when I put it back together.  I'm open to suggestions on the best way to accomplish this.

[Jeff G 78]

From the picture you posted, it looks like the valve is up.  Since they are loose, remove the springs and then see it you can grab the valve stem with your fingers and move it up and down as well as rotate it.  If you can get a good grip on it and can't move it, then you have a bent valve and piston damage at a minimum.  If you can freely move the valve up and down all the way and rotate it without the stem movingside to side, you might have gotten lucky.  Even if you did bend a valve, it's not always a total loss.  I've bent valves and simply polished the piston divots and replaced the valves.  If the head has gouges, it can be welded and reshaped.  It is also important to learn why the damage occured.  How much has the engine been run since it was rebuilt?  I know you said that you paid about $3k, but that doesn't mean the shop had any clue what they were doing.  I have built engines for half that and raced them.

[Dolfinz]

The engine doesn't have 2 miles on it.  I drove it about half a mile before it developed the starting/alternator issues.  Then I got it running and drove it 2 blocks and the rocker arm came off.  $1250 for the rebuilt head, $1500 to have the head and block put back together with timing chain and front end in place and a few hundred to a friends son who helped me put it the rest of the way back together.