Stuck valve?

[Dusty B]

Getting around to evaluating the new Cub changed oil transmission fluid air breather gas tank compression Check 60, 110, 125, 0! . First gas is stuck valve! Any recommendations for checking that out or loosening it up without removing head? Pull valve cover and verfy non-movement? Also going to have to remove dried flaky crud from gas tank! With everything being dry is vacuuming a safe process? No sediment bowl only an in-line filter! That will be corrected!

[staninlowerAL]

I had a similar situation on a non running cub that had sat in a barn for 30+ years. Penetrating oil of your choice into the cylinders and soaking the valves from the top and lower end after removing the valve cover, gently tap the stuck valve(s) from the top and bottom, needlenose vice grips to wiggle the valve stems and you should be able to eventually free it up. Oh yeah, a large dose of luck and patience, it probably won't happen right away. JMHO, Stan

[Dusty B]

Valve cover off, flat bar, bingo! valve popped down - 60# pressure dry! going to reinstall carb, run to warm up,ajust all valves and hopefully with seafoam in gas and oil sticky valve problem will disappear!

[staninlowerAL]

Be prepared for it to stick again until you can get some lubricant on the stem. Also MMO is a good additive for sticky valves, might make the engine smoke a little but that's to be expected.

[NJ Farmer]

Use Marvel Mystery Oil in the fuel (at the correct mixture on label). Works perfectly since 1930’s for stuck rings or valves the AAC used it in WW2 on big radial engines! I swear by the stuff today in the fuel…..not in the oil that’s a different discussion altogether!

NJ Farmer

[Dusty B]

Thinking a can of sea foam in pony tank and oil run it until everything is hot! compression did come up to 60# dry so do have hopes for it!

[Magnum]

I have freed up my share of stuck valves , patients is key . I used lots of penetrating oil some home made some store bought In fact I have a barn find cub that was locked up , and had some sticky valves . With some time and patience it is now running and running real nice with no smoke. I think luck and an owner from 35 years ago took real good care of that one. In fact it's nearly finished a restoration which I will post pics of it soon .

[MontanaMan]

I have freed up my share of stuck valves , patients is key . I used lots of penetrating oil some home made some store bought In fact I have a barn find cub that was locked up , and had some sticky valves . With some time and patience it is now running and running real nice with no smoke. I think luck and an owner from 35 years ago took real good care of that one. In fact it's nearly finished a restoration which I will post pics of it soon .

Cant wait to see it! I will be getting into my 1948 Cub soon......