Zero compression #3 cyl after sitting 1 year

[xirdneh]

the car ran fine a year ago, it has not been started since i parked it 1 year ago.
today i fired it up but cylinder #3 was not working
i did a compression test and #1,#2 and #4 were around 180 but #3 was zero
i am guessing a valve is stuck open

[Gottolovem]

Yep i bet it is a valve

[xirdneh]

i removed the valve cover this morning
the exhaust valve is stuck
i tried tapping the end of the valve
then rapped the top of the spring
then clamped a small vise grip on stem end but could not twist it
so how do i go about freeing this thing up?

[dlb]

if it's stuck open, that means it's already at or near the bottom of its travel, right? so i'd try some sort of slide hammer technique so you could tap it upwards, so to speak. not sure how i'd accomplish this though.

[Gottolovem]

Is the shaft dry?
Try some atf to "free" it up maybe

[xirdneh]

I am thinking that letting it warm up while idling on 3 cylinders might help
The little bit of expansion might let it move
Or will remove spring and valve stem seal to squirt some lube

[Jonymoto]

If you remove the cam shaft and hit the top of the shank and spring with a hard plastic mallet it might free up especially after following Dan's suggestion.

[xirdneh]

First removed rocker assembly. Unfortunately I tried tapping the end of the valve shank. That only compressed the spring more and I could not get the spring compressor on cause there was not enough gap in the spring.
I stuffed rope in the cylinder thru the spark plug hole and rotated piston up as a precaution just in case valve loosened enough to drop. Next i used a short piece of thickwall pvp pipe set on top of valve spring and smacked with mallet. The plan was for spring to compress a bit and pop back up loosening the valve but that did not work. Then clamped a vise grip in end of stem and barely managed to wiggle it enough for spring to expand. That allowed me to get the spring off with spring compressor. Pried valve stem seal off. Reclamped vise grip and after squirting thin lube on stem began trying to wiggle stem back and forth. It only moves about 1/32 of an inch so I will keep soaking and wiggling.

[xirdneh]

finally got it free enough to work but it never did get smoothly loose
engine runs now

[splatterdog]

I might be a little concerned that the tight valve might take out the guide. More soaking or repeated engine foggings? Neighbors love seafoam style tuneups..

Fluid film smells neat. Fogged the mower last year with it.

[dlb]

what's an engine fogging, SD?

[Jonymoto]

Is that when you spray water into the engine whilst it is running to remove carbon build up?

[rer233]

Fogging is when you spray a petroleum-based liquid down the throat of the carb on a running motor just prior to shutting it down (esp. prior to winter or other long term storage.) I do it to my boat motor every time I put it back on the trailer (along with flushing the cooling system with fresh water.) I just fill an old squeeze mustard bottle with Marvel Mystery Oil and have at it!