0.15" is the valve setting intake & exhaust, if you have a gas engine set the plugs at.035" LP 0.25" check compression dry then wet, then do the tune-up. Make sure to clean the points with a clean paper towel, just open the points with a screw driver insert the corner of a paper towel and slide the paper towel through the points to clean. Base setting for the timing is to 1. Disconnect #1 spark plug wire at the plug. 2. Turn the key switch to on 3. Loosen the distributor and rotate until you get a spark. 4. Tighten the distributor and re-install the plug wire 5. Start the engine, adjust the carb air mix and idle. F163, Y112 etc... Engines are very resilient and can take real beating such as lack of maintenance etc... This is all "old school" basic stuff and has worked for me every time.