hi this is mark from ereplacementparts.com you know last night I was doing a small drywall project and in the middle of that the fan on my drywall gun exploded and we're gonna show you in this video how to repair that we'll start by removing the back portion of the grill here that'll allow us access to the brushes which I need to remove from the armature so I take a little pant clip off the next fasteners are a Torx number 20 all right with those screws removed and I can remove this rear access plate and here's the brushes here and here and they just simply lift out of the housing that's all we need to do back here now we can continue on to the front of the tool on the front of the drill there's three more screws that and that will allow us to remove the gear housing from the motor housing okay now I can separate the two housings now we have this plate which the armature is pressed into and I can go ahead and pull the armature out of the machine now I might need a screwdriver to kind of pry that get it started and there's the armature and what's left of the broken fan just fell out okay here we have the old armature and the fan goes on to the armature right here it's where it should be now the manufacturer only offers the new fan as part of the armature assembly so I'm going to have to replace the entire armature which means we have to remove some pieces and transfer them to the new armature so let's start by pulling out the new armature here and you'll see which pieces we need to transfer over here you can see the old armature in the new one I'm gonna have to transfer over a couple of bearings and a little retaining ring so we'll go ahead with that okay I'm going to remove the rear bearing here or the one closest to the commutator and to do that I'm going to use a small bearing puller to use a bearing puller the center portion of the puller goes onto the shaft of the armature there's usually a little dimple milled in there that you can use to Center the puller and then the jaws go underneath the bearing like that and now we just turn the center portion of the puller and it will pull that bearing right off the shaft for us just like that next we'll remove this plate from the armature to do that I'm going to use a vise I've adjusted the vise jaws so I can slide the armature in between them and the plate is sitting on the top of the jaws now with a mallet I can tap on the the end of the armature shaft like that and that removes the bearing from the plate okay to remove this bearing I'm going to use another specialty tool this is called a bearing separator and I simply clamp that the separator around the armature shaft underneath the bearing set the separator over my vise and now we can tap the armature out or off of the bearing like that the last part we need to remove from the old armature is this split retaining ring and I'll use a pair of retaining ring pliers for that just like that now we'll go ahead and replace the parts to remove from the old armature onto our new armature and I'll start with that retaining ring again then the bearing to press the bearing onto the shaft this time I'm going to use my vise again to press this one on I'll simply set it on top of the vise jaws like that and then use my shop hammer to seat it in place now on this side we have the dividing plate goes back onto the bearing and again we'll just use our vise to see that in place now we'll do the bearing on the commutator side of the armature and that should do it now we'll place the armature assembly back into the motor housing I'll replace the gearbox and the three screws that secure the two halves together now we'll continue to the back of the screwdriver the next thing I'm going to do is replace the brushes there's a little tab on the brush holder that fits into a groove on the motor housing this goes in like that same thing on the other side get the wires out of the way so they don't get pinched by the rear housing when we put it in place and then that rear housing this slides on and again three screws secure it in place and the last piece is the belt clip and that's all it takes to repair a bad armature or a broken armature fan on a porter cable drywall gun if you found this video helpful please feel free to leave a comment or ask us a question you