Hello everyone, new here. I am a longtime air-cooled VW person and traditional Ford hot rod dreamer. I've got a running-when-crated 59AB and was doing some cleanup and saw what appears to be a stuck valve. (Pics attached). I could use some confirmation on my first steps here and any 'gotchas' as I'm completely new to these engines: I was just going to put some Mystery Oil on the spring and into the cylinder. Maybe buy a pickle fork and cycle it with that?
Adjustable lifters and a pretty clean valley for a flathead. You are on the right track. You need to get the MMO to penetrate the valve guides and it should free up.
With the head still on, I have been able to go in the spark plug hole with an allen wrench and tap the valve down.Oil it up, trying to squirt under the valve and onto the stem. Try to hit the valve center, not too violent, dont want to bend it
Most of the flatheads I have bought in car or out had a stuck valve. It's an assembly and if the suggestions don't free it up it might be time to pull a head and pull out the stuck valve. There are little keepers that keep the assembly in the motor - you can buy a fork like pry bar from one of the parts suppliers to help removal. At this point with the stuck assembly out - you can still soak it a little more to see if it will free up. . As cheap as the NOS parts are I've always just buy the NOS parts for a new assembly and have had good luck. Good luck with yours !
Spray the mystery oil into the intake port, that will get the oil on top of the valve guide. Use a flathead valve tool (long bar with a fork on the end) to pull the valve down and push it up. It should loosen up after a few up and down cycles.
Do not hit, tap or anything else to the top of the valve. They bend very, very easily. Spray a penetrating oil into the intake port, not into the spark plug hole and let it sit for a few hours. I like PB Blaster for these things. Now, take your valve bar, as mentioned, and try to move it up and down until it's totally free. Don't force it too much. If it doesn't move properly, spray and let it soak again before the next try.
Warm it up a little with a heat gun to expand the valve guide. Being a intake valve it’s probably varnish from the gas that’s got her stuck. Sent from my iPad using The H.A.M.B. mobile app
Once everything is moving smoothly & working as advertised again, a lot of guys run a few ounces of Marvel's per tank of gas to keep it that way. It does seem to help.
Got it unstuck. The FH valve tool was critical. Also, re-reading this thread and realizing that using it in reverse i.e. to both pry the valve up and pry the valve back down was key to working it back and forth.
good for you! squirt some marvel mystery oil on the stem and run it. may still stick occasionally, but it will live again with some running