Hi all. I'm new to the forum here, and hopefully someone knows about this issue and what to do about it. I have a Bostich 16 gauge straight finish nailer (pneumatic) that won't fire when cold. I'm not talking about freezing weather. I mean even if it's 50 or 60 degrees out, it won't fire till I warm it up. I keep a heat gun in my truck and have to warm it up for a while before it will work. It has done this since I got it, but the repair shop couldn't find anything wrong with it when they took it apart. So I've dealt with it for a few years. But I'm tired of it and am about to buy another nailer, but figured I'd see if anyone knew what the problem is. When it's cold, and I try to use it, it sounds like it wants to fire, but all that happens is I hear air coming out somewhere. Sometimes when it's almost warm enough, I can get it to work without warming it up by doing the following. I unhook the hose, hold the trigger and press the nose to the workpiece and connect the air hose while doing that. Sometimes that will make it fire and then it will start working. However that only works at temps just a little lower than what it would work at normally anyway. If it's above 70 or 75 degrees or so, it works great! Any ideas? Thanks!

FN1664K

Thank you for the quick response. I guess if there's a groove, then I would need a new cap as well, right? How do I know what o rings are needed with the head valve? Do I just replace all the o rings above and below the head valve, or what?

Thanks again for your time!