valve question

billb61460 · Postby **billb61460** » Mon Aug 20, 2007 6:41 pm

once the head was off, three valves were stuck on the 47. We sprayed them with a solvent and the three freed up and were working fine. We cleaned the valve heads and the seats with a wire brush and steel wool. They all seat very nicely now and look free of any carbon build up. But, one started sticking again in the up position. It was one of the small ones, is that the intake or exhaust?

Question. Should if it sticks again, should I just blast it again with the spray until I get consistent movement over a couple of days or does anyone have any other tips? I would like to avoid doing a valve job on that one if it is avoidable by trying simpler steps first.

Thanks.

Postby **Bigdog** » Mon Aug 20, 2007 7:03 pm

Exhaust valve - try adding a little Marvel Mystery oil to your gas tank.

billb61460 · Postby **billb61460** » Mon Aug 20, 2007 7:21 pm

thanks BD. I just bought a quart of that the other day. Funny, I remember my dad using that 35 years ago. He used it for everything and it seemed to work for everything.

Postby **Eugene** » Mon Aug 20, 2007 7:43 pm

Exhaust valve freed up, sticks occasionaly. Question. Should I blast it again with the spray until I get consistent movement over a couple of days.

That's what I would do.

Remove the valve cover. Leave the head off. Rotate the engine by hand. As each valve lifts, spray solvent on the valve stem. From the bottom, spray solvent on the valve stems.

Before you get ready to button up. Squirt a drop or two of oil on the valve stems and rotate the engine to lub the valve guides.

Marvel Mystery oil or SeaFoam in the fuel tank and oil.

Eugene

Forgot. Put a couple drops of engine oil around the edges of each valve lifter.

KETCHAM · Postby **KETCHAM** » Tue Aug 21, 2007 5:45 am

Might want to lap the valves anyway to get them to seat right.I'd replace the springs also.You can check to see if they leak but spraying carb clean in them with the valves shut.If nothing leaks down your in.I did a quick job on my 47 [new springs and lapped the valves] and glad I did.One of those 'while your there things"Kevin

Bus Driver · Postby **Bus Driver** » Tue Aug 21, 2007 6:01 am

For the valve that continues to stick, the problem could be the lower end of the valve stem that sticks just as the valve reaches the highest lift. Carburetor and choke cleaner might help. Lifting the valve higher than normal a few times might help. Removing the valve and cleaning the stem might help.

Postby **Lurker Carl** » Tue Aug 21, 2007 7:08 am

My experience with sticking valves has shown the "glue" is in the valve guide, not just on the valve stem. It's very much like the gummy goop left behind when gasoline evaporates and you really need to take things apart to clean that stuff out of there. Otherwise it's gonna be a continuing problem.

billb61460 · Postby **billb61460** » Tue Aug 21, 2007 7:51 am

Thanks everyone. I will try the simpler solutions first. If those don't work, then I will do the valve removal, cleaning, seating etc after Cecil's demonstration in October. I will keep everyone posted on progress.

KETCHAM · Postby **KETCHAM** » Tue Aug 21, 2007 9:37 am

Look foward to seeing you at Cecils!!!Kevin

Postby **Eugene** » Tue Aug 21, 2007 7:08 pm

The question was "How to free up a stuck valve?" Actually, since the head is off, I would remove the valves, clean them up, lap them, take a rifle bore brush with solvent and clean up the valve guides. Basically, do a complete valve job.

Better now than after it's all buttoned up and finding that the valves leak.

Eugene

Farmall Cub

valve question

valve question

Re: valve question

Who is online