I have a Paslode IM250 A cordless nailer that my Dad left me when he passed. First cordless one I have ever owned, although I have used numerous pneumatic ones. I can't get it to fire. I have tried all the troubleshooting that I've found on the web and still can't get it to fire. Everything functions as it's suppose to, just no bang when I pull the trigger. I was looking at the spark plug in tool diagrams and the tip of the spark plug appears to stick out below the plastic. The one in my gun doesn't do that. It is actually above or close to even with the plastic. So, is the end of the plug suppose to be below the plastic or not?