Valve Spring Came Off, Valve Stem Stuck Closed Position

[mderosa3]

Good afternoon

2011 Ford Expedition King Ranch 208K miles. So after having miss fires on passenger side cylinders and random rich mixture codes, I decided it was time to take off the valve cover and inspect. This is the first time the valve cover has been off this engine and the engine has not had a new timing job. All original parts.

Discovered on the #2 cylinder the aft intake valve rocker completely gone but recovered it (all chewed up) as well as the valve spring completely off just sitting in the top of the space. Found the retainer but no signs of the keepers. The valve stem is in the full up position (not sure if this means I'm lucky) but also not sure if its stuck in the closed position because of unknown reason. Before attempting to replace the spring, keepers, retainers and rocker arm any suggestions on verifying no internal damage to piston area and or cap of valve stem? I will most likely be doing a full timing job but want to make sure this is salvagable before putting that amount of money into this engine. At a minimum if the stem is still functional I will also be replacing the camshaft as the lobe is chewed up. Any thoughts, inputs, suggestions would be greatly appreciated.

 

[JamaicaJoe]

I wonder if the valve stem seal is holding it into place. A borescope of the cylinder should be done. If all looks good, if you can rotate the piston to TDC with the intake and exhaust closed (firing position) you could then use compressed air to check for air leakdown. Be sure to anchor the faulty valve somehow. If there is no gross leakage, assemble the valve with new rocker, springs , seal (if required) and retainers and perform a normal compression and leakdown test on all cylinders. You may want to ensure that the valve will open under leverage when you get the springs and retainer in place so that the new rocker and cam dont get further damaged if the valve stem is bent.

 

[JamaicaJoe]

There is an old trick, using rope, inside the cylinder, to keep valves held closed while installing the spring.

 

[GlennSullivan]

I assume you know that the cam will need to be changed as that lobe is badly damaged. Do as Jamaica Joe said, borescope first. Then support the valve externally and rotate the engine until that cyl is at TDC (both valves closed). Then attempt to spin and move the valve up and down by hand to see if is bent. You should be able to rotate it even with the seal in place. If it is not bent, then try compressed air to see if it is leaking.

If it is bent and / or leaking, the heads or at least that head will need to come off. With over 200K miles, if you are planning on keeping it, I would install a remanufactured engine instead of just having the heads done.

If it is not bent / leaking, you can try installing a new spring, retainer, locks, follower and cam. It will be a risk though and a lot of wasted time and money if it does not pan out.

 

[mderosa3]

Thanks Jamaica Joe and Glenn for the replies and suggestions. I took a look yesterday using an older borescope camera with not so great lighting. Everything looked good as far as I could tell. Might look at renting a better camera today and take one more look before attempting your suggestions of checking valve movement and leakage. The valve seems pretty stuck, i attempted to push slightly down while holding it and had zero movement downward. Definitely will be replacing the cam as well as all rocker arms if engine is still salvageable. I will post an update on findings.

 

[mr_dave]

My concern would be if the spring is gone (and the valve is just floating) then it almost certainly contacted the piston at some point. Even if it didn't cause much visible damage, it's probably bent enough that it wouldn't seal properly.

Considering that + unknown metal pieces (and/or shavings) throughout the engine + cams + all new rockers/lifters + all new timing components, it would probably make sense to just get a remanufactured engine at that point.

 

[mderosa3]

Very valid concern Dave. The fact the valve is fully in closed position is interesting but not being able to move under normal pressure without spring leads me to believe its either bent, extensive carbon build up, and or seal failure. I'm leaning towards bent but will try Joe and Glenns suggestions first before throwing in towel.

 

[Dahammer]

The valve should not move by hand. If it did, then the head is no good. Exhaust gases would bypass the exhaust manifold thru the stem and fill the head with heated gas, and blow out the seal.
Replace one head or two heads altogether if you want to.

 

[mderosa3]

Update: For those that might run into a similar situation.
1. Followed the advice to borescope into cylinder to check for damage. None observed on both the piston head as well as all 3 valve caps.
2. Performed leak down test after removing the remaining two rocker arms(followers) and no sounds of leaking from the intake/exhaust/or head.
3. Replaced the camshaft, valve spring, retainer, keepers, rocker arm, and lifter. They all showed signs of damage with the rocker arm and camshaft being the worse. Used all OEM Ford parts and the rocker arm removal tool https://www.amazon.com/dp/B00JMLEWXY?ref=ppx_yo2ov_dt_b_product_details&th=1
4. Replaced camshaft phaser bolt, replaced valve cover gaskets, and performed oil change.

Followed the following procedures to remove camshaft. https://apdty.com/blogs/news/how-to...-mountaineer-for-engine-variable-valve-timing. After I replaced valve spring, keepers, and retainers, I ensured the valve would move up and down by manually rotating engine with an old but still good rocker arm.

Engine runs very smooth and no miss fires. Will do a full timing change as well as update the oil pump with a high volume Mellings and replace all rockers with new designed ones when the temperatures here in Florida cool down this fall. Thanks again for the suggestions.

 

[GlennSullivan]

Glad it worked out for you, if you are not already, you should be going to church, because the odds of all being good were not in your favor.