Does anyone know if Honda uses or recommends using spark plug grease on the threads when installing plugs? I removed the plugs on my wife's E to adjust the valves. I was shocked at how much force it took to break them loose. They squeaked really loud as I turned them. That can't be good. When I put it back together, I used a small amount of the grease and torqued the plugs to 18N. Is there anything wrong with using the grease?