If it's a hammer, rather than hammer drill, then I wouldn't bother. Assuming you're using it on limestone, they shake buggery out of you & leave the rock untouched in my experience!
If they are that small & you obviously use a genny, then why not use a drill, plugs & feathers?
Easy, if a little time consuming to make but combined with a genny powered drill, so very effective.
As long as the genny runs you can keep digging & no fumes - try it, you'll love it!
i took a full size kangoo down before( flat out on belly all the way). and it got me a break though. cause i dig on my own i need to get alot done in the time what i've got.