Also, if the compression test is low you can apply air to that cylinder with both valves closed.
Air exiting the carburetor means a burned or bad seating intake valve.
Air exiting the exhaust pipe means a burned or bad seating exhaust valve.
Air exiting through the oil fill on the valve cover means air is getting past the rings.......or there's a hole in a piston. Either should be evident on the compression test, but applying air to the cylinder as described will narrow it down.
Do the compression test DRY. There is no need to do it wet as long as you do the air test as I outlined.
