Hi, Generally, get the hood out of the way, remove the four bolts holding the rocker arm cover on(3/8" socket.) Loosen the lock screw in the center of the pivot(could be a Torx or Allen) and rotate the engine clockwise( as viewed downward toward the flywheel screen.) The spark plug should have been removed and something loosely placed in the hole to observe the movement of the piston. When the piston goes past the top and moves 1/4" down, then adjust the valves to 0.005"(note: this should be at the time when both valves are closed and it may take multiple revolutions to be sure of the correct time as the valves will be "rocking - one closing as the other opens every other revolution.) Lock the adjustments down and reassemble.
You can adjust the valves on your 17 horsepower Briggs and Stratton engine by turning the adjustment screws. The adjustments screws will determine how much fuel goes into the piston chamber.
Try watching the video in the link below.
The valve clearance is set by grinding the faces if there is too much clearance or grinding the tip of the stem if there is too little. If it is a OHV engine you can easily adjust the valves. Try going to the link below for a video that shows how to adjust the valves.
You do not state if it is a single or a twin (which it could be of either at that HP) so links to each below:
Valves 21 hp Briggs and Stratton Intek V Twin can be adjusted by increasing the torque on screw band with a right rotation. This can eliminate some leaking problems.
Yes They Do
If the valves are new you grind the end of the valve stem to the proper height . Otherwise you just clean the valves up real good and put them back in , there is no other adjustment .
This video will show you how: http://www.youtube.com/watch?v=NjzX-PUjKmo
Even though an Intek is not shown, it would be the YouTube video below.
If it is a Briggs and Stratton engine, it sounds like you might have to adjust the valves. There is a built in compression release that lets it crank over easier. If the valves are too loose it will not release the pressure.
You can not set the timing. It is determined by the keyway between the flywheel and the crankshaft. It only goes in one place. You can adjust the coil, the valves and the carburetor.
The most popular place I know of for instruction is the YouTube site at the link below.