stuck valves

[Deleted User]

does anyone now the best way to un stick some valves besides tearing it down its a 1950 commadore 8 has been rebuilt

Marconi

Pour in/ fill cylinders with Marvel Mystery Oil, Diesel fuel, ATF, or any one of your favorite penetrating oils and wait for about a week for it to creep down between the valve and guide. Take off the valve cover and try to pry the valve down or push it up if stuck closed. Don't get tooo heavy handed or you could bend the valve or break the guide. If you try to beat the valve down thru the spark plug hole, you'll probably bend the valve. Your best shot is to pull the head and use the penetrating oil if they're rusted/ stuck, if they'r just gummed up then just soak them and try to move them. Good luck!

oldhudsons

and if prior advice doesn't work just pull the head whence you can pull out the valves; wire brush the valve stems to get them clean of whatever, perhaps put a small brush of some sort on an elec. drill to clean out guides & button it up.

lostmind

If the vehicale runs, you can use combustion cleaner
down the intake. WD 40 down the intake while running might also work.
I had this problem caused by stale gas.

Roy

Geoff

You can try removing the valve cover and getting vice-grips on the bottom of the valve and turning back and forth. Will work if valves are not badly stuck. But prior soaking in penetrant as advised is essential.

bull_islander

If you try the other lubricants and they don't work (because everybody has marvel and wd-40 in their garage), try KROIL. Get a small can (it's all you'll need). I tried the others with no success, finally bought a can of KROIL (about $10) and the valve started sliding down on its own after all of 5 minutes.

Here's a link to their web. You might be able to find some local if you have an industrial type shop around. http://www.kanolabs.com/

Just take the plugs out of the head and spray it on and around the valve. I had already pulled the head off by the time I got the kroil. Which I wouldn't have had to do if I'd tried this stuff first.

[Deleted User]

About 10 years ago, when passing thru Nashville, TN on Thompson Lane we passed the Kanolabs office, pulled in and purchased a gallon, which I split with a good friend. The lubricant takes very little to do the job, so my 1/2 gallon has lasted 10 years. Good stuff, try it.
When you go to Pigeon Forge, just go thru Nashville and buy some, no shipping.
Thanks, Bob P

Jon B

Of course you can also try spraying UP into the valve guide from below, by inserting one of those red straws (that come with the penetrating oil spray cans) into the hole in the plastic spray head. Removal of the valve cover's required, naturally.

I wonder if one might back off the tappet (by turning the crankshaft) and then place a small shim between it and the valve stem, so that (the next time you turn the crankshaft) it would force the valve up slightly higher? This might help "break it loose." However, I don't know how much higher it could go before it "bottoms out" on the cylinder head. A bit dangerous, I suppose.

When I got my 6-cyl. 3x5 the valves were jammed tight and even when I pulled the head I had to hit them with a hammer, hard, to force them down and get 'em loosened.