Freeing a stuck valve.

This may be a long shot and I have an idea on 'how' I can attempt this, but has anyone ever freed a stuck valve on a cylinder head without removing the head completely?

I did some investigation on the Camaro's 305 this past weekend  and I have a singular stuck intake valve. The rocker was off the valve (undamagaed) and the push rod is straight. I tried whacking the valve with a piece of wood and I was met with a hole in said wood that went fairly deep.

My thought process is using an over head valve spring tool and compressed air to remove the valve spring, try a little bit of penetrating oil around the valve guide (evidence points to it being stuck in an 'open' position, let it soak and attempt whacking just the valve stem with a piece of wood or something a bit sturdier. I plan on doing an oil change after all this if this works. I know the 'proper way' is pull the head but the rest of the head looks healthy so I was hoping to find an easier way.

What does the hive say?

If the valve is lightly stuck by corrosion on the stem, you can sometimes tap them down and when they come back a bit it scrubs the rust off.

Once you tried that and it stayed solidly stuck, just save yourself useless effort and remove the head nd do it right, as you are most unlikely to be able to free it up externally.

Im in a weird place right now. I have a set of vortec heads to go on I picked up cheap, I just don't have everything else to put them on and be a running vehicle again just yet. I was hoping to only pull the heads once if that makes sense?

I may pull the spring off and see what the rest of the valve stem looks like since I can't see the stem right now. And button it back up for now until I have everything to the swap over and keep the car confined to the yard while I source everything else for the swap / planned upgrades. 

Head of the valve has been hit or other wise damaged which bent the stem near the guide.

SWAG

Put the piston of the offending valve at TDC.  Remove the spring and valve seal, shoot it with PB Blaster.  Wait, tap, wait, tap; if it doesn't want to go something's wrong.  You can grab the valve stem with a portable drill and rotate it, check for wobble, (bent stem)

Only a bee in the hive....

Sorry if its stuck and you can get the head off its cheaper and easier to pull it. If its stuck its stuck for a reason I guess is what I am saying. 

Its not stuck down far so I don't think its made contact with the piston. The rocker came off and the push rod is straight, so I am mostly hoping it's just gotten stuck in that position from sitting for so long (was parked 14 years ago, minimal run time in that time due to seized caliper). I'll need to borrow the spring compressor and pull the spring off to get a better look at it. 

As I said, if I'm pulling the head I don't see myself fixing this valve when I have a different set of heads to put on, just not everything compiled as of yet to put them on yet. Mostly the gaskets, valve covers and the little things needed to 'complete' the swap. 

I would be tempted to try to add some spring pressure via a screwdriver or pry bar between the coils of the valve spring. Might be enough to break it loose and get things moving again. 

Use a small hammer.  If that doesn't move it, use a bigger one.  Failing that, remove the head and replace the bent valve.

Does the rope through the sparkplug hole work for a stuck-open valve?  

You really have nothing to lose, as it will either free up or it won't.  Start small and get more extreme.

I vote for pulling the head. I had a 305 self destruct from a stuck valve, ruined everything. It is not worth the time of messing with it, the chances of it sticking again and detonating the engine are too great.

Tyler H said:

Use a small hammer.  If that doesn't move it, use a bigger one.  Failing that, remove the head and replace the bent valve.

Does the rope through the sparkplug hole work for a stuck-open valve?  

You really have nothing to lose, as it will either free up or it won't.  Start small and get more extreme.

It would work to keep the valve from dropping into the cylinder when you take the spring and retainer off so you can try to break it loose by turning the stem.  of course all of these ideas revolve around the valve just being stuck/gummed in place and not bent.  I've found lug nuts in double digit mile engines that have sat in a barn for 20 years.  you never know what someones grandkids might have dropped down the intake while the thing was sitting up.  

Tyler H said:

Use a small hammer.  If that doesn't move it, use a bigger one.  Failing that, remove the head and replace the bent valve.

Does the rope through the sparkplug hole work for a stuck-open valve?  

You really have nothing to lose, as it will either free up or it won't.  Start small and get more extreme.

That was essentially the plan, with the spring installed and working on my own I'm uncertain 'IF' there is movement or not. When I pulled the valve cover, the rocker was off the valve and I was unable to reposition the rocker into place without loosening the stud on the rocker. Everything else look 'okay' and its been mostly the racket from loose pieces that have made things more worrisome. 

In reply to Strizzo :

It's been in 'my' yard all this time and the hood had been in place but not attached. Being a steel hood, my nephews wouldn't have the height or strength to get the hood open very far thankfully. Rodents on the other hand....