Small Engines (Lawn Mowers, etc.): Tecumseh valve adjustment, murray riding mower, feeler gauge

Question
Ben, I have a Tecumseh 17.5 hp OHV vertical shaft engine, its on a 2000 model year Murray riding mower. How do I adjust the valves on this motor? It was running great, then just shut off. I noticed there was no suction on the carb which told me to look at the valves. So, I removed the valve cover and on the intake side, the rocker was completely off the push rod. I have researched this problem and still don't know how to adjust the valve. Where would I place the feeler gauge? How would I know when the valve is set, aside from the engine running again?  Everything I've read so far says there should be 2 nuts, one to adjust with and the other is to lock the other in place, mine only has one nut on each valve. Do these just tighten down (non-adjustable)? The model number is rubbed off the motor and I'm hoping these motors are pretty much all the same. Its a 17.5 hp Tecumseh Enduro OHV. Any help would be greatly appreciated. Thank you in advance.

Answer
Sam
You need to insert the feeler gauge in between the rocker arm and the top of the valve and spring then tighten the nut for your rocker arm till the feeler gauge fits in comfortably not to snug, its a good idea to recheck with feeler gauge after 1-2 hours of normal running

To adjust the valves, remove the valve cover, and then rotate the crankshaft by hand until both valves are fully closed with the piston at TDC on the compression stroke. If one valve opens slightly and the other closes slightly and vice-versa while rotating the crankshaft back and forth, then the piston is on the exhaust stroke and the crankshaft needs to be rotated one full turn (180°). This will guarantee that both valves are fully closed so accurate valve adjustments can be made.
Valve adjustment is made with the engine cold, with a flat feeler gauge and on the 10-16hp engines, with the lifter held in place with a slender 1/2" open-end wrench and turning the adjuster screw in the lifter with a 7/16" open-end wrench. When checking valve clearance, always have the piston at the TDC position on the compression stroke. And make sure the ends of the lifters and valve stems are ground square for proper adjustment.

Check the valve guides for wear. Most of the time, the exhaust guide will wear more than the intake. The maximum wear limit on the 7hp and 8hp engines is .005" for the intake,.007" for the exhaust. And on the 10hp, 12hp, 14hp and 16hp engines, it's .006" for the intake and .008" for the exhaust.