No question is silly. The short answer is no, the slide valve is about 90 degrees out of phase with the piston ignoring any lap or lead. There are some excellent animations on line and this is not one of the best. The long answer could easily be a lifes work and is beyond me. Andy
If there is no lap then the valve will be at the end of its stroke when the when the piston is mid stroke. In this simple arrangment the piston and valve are 90 derees out of phase. If there is lap then for a slide valve it will need to be advanced (given lead) such that valve has travelled in advance of the 90 degrees such that the valve is just openning the inlet port appropriate for the piston at top or bottom dead centre.
Too late in the night for me to write anything more profound.
Remove the cover from the valve chest. Reinstall the nut/bolts to hold the steam chest in place. Rotate the engine until the piston is at TDC or BDC. Now rotate the valve eccentric (in the direction you want the engine to run) until the slide valve is just opening up the steam port on the end that the piston is. Tighten down the set screw on the eccentric, bolt the cover back on and you should be good to go. gbritnell
Hope this helps? Best of luck, Regards, Alasdair __________________ Talent unshared is talent wasted.
Both steam4ian and Stuart's (via alasdairm) give the correct basic answer but both also state 'TDC or BDC'. Perhaps it is preferable to say TDC AND BDC, as a check at both dead centres so that the right thing gets embedded in the brain for the future setting on a less simple engine?