I should be able to adjust it with the eccentrics the way they are. So I leave the piston at TDC. Loosen the set screws on the eccentric that is headed "upwards" and rotate it until I start to get air out of the top drain cock right ?
jon
For the top of the cylinder: The valve link should be heading downwards. It's opening the top port to the steam chest. Upwards would be opening the port to the exhaust.
Jon, if you could measure some fundamental valve dimensions, that would help with the setup.
The first picture defines "Admission Lap" and "Exhaust Lap" both measured with the valve in mid-position. The best way to get these dimensions is by measuring according to the diagrams which follow, two dimensions from the valve itself, and two dimensions from the port face.
The final dimension needed is the stroke of the valve, which is twice the eccentric throw.
Ok...................I am an idiot............I tried to monkey with it last night and now all I have is reverse..................... I should have paid closer attention in kindergarten when they were going over valve adjustment on steam engines.
What do I do now ? Crack the steam chest so I can see what is happening ? I am not clear which one of the eccentics is "doing the work" Is there a way to tell by their position relative to the way the stephenson link is thrown.
I am feeling kind of stupid now. If anyone has a good lik they can refer me to that showes the set up of the eccentrics relative to each other I would be grateful. I started to work my way thru the section in the UK steamboating guide but I glazed over........beyond my pay grade........
JonRiley56 wrote:What do I do now ? Crack the steam chest so I can see what is happening ? I am not clear which one of the eccentics is "doing the work" Is there a way to tell by their position relative to the way the stephenson link is thrown.
jon
The rod that is in line with the valve stem is the one "doing the work", It's eccentic should be leading the crank.
Do a Google on "Stephenson valve gear" and many animations will be listed. The Wikipedia animation is pretty good and while not showing the crank it doesn't confuse things with all of the locomotive "extras"
I should have paid closer attention in kindergarten when they were going over valve adjustment on steam engines.