Tried to adjust my valves today while doing an oil change. I couldn't get anything done with my huge wrenches... When I tried adjusting, all 3 nuts rotated together. Is there any chance of my valve falling into the cylinder if all 3 were turned together? I read someone had that happen. Does the oil have to be drained in order to do it? I put the cover back on already and filled the oil. Is there anywhere I can get the special wrenches cheaply or borrow them? $50 is way to much for me for tools that will only be used every 2 years and I'm already completely broke from buying over $100 worth of filters and fluids...