valve gear question

Hi steam guys, Here is a good challenging situation for all. I am trying to set-up the valve gear on a 1/2 scale Case engine. I can have the reverse lever pulled back, rotate the eccentric and adjust the valve for equal leads, about 1/16" or so. But when I move the lever forward, rotate the eccentric, the valve is very unequal over the ports. About 1/4" on one port and none at all over the other one. Is the valve too wide? Is there something else I should try? The eccentric has an 7/8" throw which is supposed to be correct.

I welcome any advice. thanks MARK

That's a hallmark of the Wolff reverse. The valve will never have equal openings at both ports in either forward or reverse motion. It will, though, be MORE equal in forward (belt pulley running clockwise) motion. The "Case Steam Engine Manual" gives excellent instructions on setting things up. Many places sell this manual. It's worth its weight in gold. I'm sure it's available through GEM as well as Engineers & Engines magazine.

I agree wth Craig on this one.... Welcome to the realty of the wolf reverse. It is a quick acting gear and it magnifies any problems. Also all valve gears are affected by the angularity of the connecting rod. I usually get it as close as I can and then treak the turnbuckle until the exhaust is as even as possible in both directions. Sometimes you can change the length of the reach rod hooked to the reverse lever to help get more even valve travel. The Case Steam Engine Manuel is a good one and it applies well to other engines also...


Kens old engine page

Assuming all of the linkage & block have the proper clearences and are not loose on your Case' reversing gear, make sure the pivot pin on which the guide block rotates and the pivot pin that connects the eccentric strap to the block is in perfect alignment when the engine is on dead center and the valve handle centered. If they are not aligned, this situation needs to be corrected to equalize/minimize valve movement running in both directions I have found these two pins misaligned due to improper adjustments of the linkage, wear either in the eccentric strap, main bearings, or at some time the engine's crankshaft was rebabbitted without proper alignment, will cause the situation you have described to be compounded. A Wolfe reverse is not perfect but is a good one. The situation described above is a trait of them to look for and correct when there is EXCESSIVE valve travel while reversing with the engine on dead center.

I have a large whistle with no lever or value. Where can i download some pictures of values. My whistle has a 2" pipe thread , is 5.25" OD, and 14" overall length. Thanks