There is not a problem with getting them out. Take off what you need to get to the valve cover. Take the valve cover off. Da-da. There they are. 4 little bolts and a wire harness and those babies are outta there. Simple, Huh? Yep, even a truck driver could do that, right? Yep, but they have to go back in. No problem. Just reverse the removal process. Right? Well you would think. But wait, did you know that when you pulled the injectors out, oil has run down on top of your pistons and when you put it all back together and hit the starter, that oil has to go someplace. Well guess what? It tries to go out the exhaust, but there is too much in there. So what happens??? Well, in my case, it just bent three of the rods before it locked up. And you don't even want to know what that cost. I was sick, mainly cause I did it. Plus, Cat recommends replacing the 4 bolts per injector everytime you remove them. So, if you aren't for sure what or how to do it, do like I do "now". Take it to somebody who does know. I saw another truck that only had one injector removed and replaced and it too had a bent rod on that cylnder. So it is pretty common with the 3126 if you don't know how to do it. As for your problem, there are cups under the injectors on a 3126. They wear and let fuel in water or oil. Be smart. Pay the price. Or be prepared to pay more if you do it yourself. Me? I do external parts only now, but will not attempt internal again. Lesson learned.