Advice on resetting Intake/Exhaust Valves on a Vertical Walking-beam Engine
Posted: Tue May 09, 2023 1:02 am
Good Evening Steamboaters,
The TULE PRINCESS has been down for almost two years. But, at long last we have located suitable valves to provide Intake & Exhaust steam to her single piston, vertical engine. The old valves were 37 year old 1” Hoffman valves. The replacement Hoffmans we ordered ALL turned out to be defective and after much hassle with the Factory, even their attempt to fix the defect produced 2x defective valves. We had to go looking for as close an alternate as we could find.
The new ones FINALLY acquired and installed. The new ones are 1” Watson-McDaniel valves. We got up steam and made her wheels turn today, but the valves are not in sync and the action is not fully reliable. The timing is off. Thought the old settings would be the same. Not so. New valves need tweaking into true reliable service.
To me, it seems the Exhaust Valve on the spent piston stroke should open slightly before the attack of the reverse direction Intake valve providing compression. Then the alternate exhaust valve should open at the top of the closure of the intake, allowing the alternate reverse intake to take over the compression/release stroke. My description may not be textbook, but I am sure ol’steamboaters will know what I mean. Especially, anyone of you Captains or Engineers that have experience with walking-beam style engines.
My Chief Engineer (a veteran helicopter line Chief) and I welcome your advise and insights on how we can get this timing issue addressed.
Thank you all for you time and consideration in helping us out.
The TULE PRINCESS has been down for almost two years. But, at long last we have located suitable valves to provide Intake & Exhaust steam to her single piston, vertical engine. The old valves were 37 year old 1” Hoffman valves. The replacement Hoffmans we ordered ALL turned out to be defective and after much hassle with the Factory, even their attempt to fix the defect produced 2x defective valves. We had to go looking for as close an alternate as we could find.
The new ones FINALLY acquired and installed. The new ones are 1” Watson-McDaniel valves. We got up steam and made her wheels turn today, but the valves are not in sync and the action is not fully reliable. The timing is off. Thought the old settings would be the same. Not so. New valves need tweaking into true reliable service.
To me, it seems the Exhaust Valve on the spent piston stroke should open slightly before the attack of the reverse direction Intake valve providing compression. Then the alternate exhaust valve should open at the top of the closure of the intake, allowing the alternate reverse intake to take over the compression/release stroke. My description may not be textbook, but I am sure ol’steamboaters will know what I mean. Especially, anyone of you Captains or Engineers that have experience with walking-beam style engines.
My Chief Engineer (a veteran helicopter line Chief) and I welcome your advise and insights on how we can get this timing issue addressed.
Thank you all for you time and consideration in helping us out.