Received a hand me down impact wrench. It's old, but had served my father well for some time. I tried using it today, and all it did was mostly blow air.

I fiddled with the adjusting knob and that seemed to help some, but I'm thinking that my dad never took care of it very well. I popped off some of the nuts and took a gander to find some rust in the handle, but the 'guts' of the wrench seem well lubed and not dirty--though the lube seemed sticky.

My question is, how would you begin cleaning/repairing an impact wrench?

 

You had it down, why not go ahead and get rid of the sticky stuff and relube it. It operates off air, not sticky stuff, so getting rid of it may help quite a bit. Let us know.

 

If it's just blowin' air, more likely the rotor is sticking on the rear end plate. "Sticky lube" is not good, air tool oil is like spindle oil - very light viscosity. But also what happens often is the rotor begins to "bite" into the end plate and eventually hangs up on it. You'll have to break it down, clean everything, lap the end plates back into shape, probably change the bearings and rotor blades. Have a look at the impact components while you are in there (hammer or pin clutch), they may be ready to go. What I'm saying is it's a project , do it for your Dad!

 

thanks for everyone's input. My struggle is that it's an old tool and so there are no lables on it. On top of that, there are many little items that I have no idea what they are for. I'll go take some pics to show you what I'm dealing wiht.

I do have a question though, what is an "end plate?"

 

I have had very good success using WD-40 to tune up my air tools when they get a bit sluggish.

No need to take anything apart for this.
Just use the nozzle attachment on the WD, disconnect the tool from the air, put the nozzle in the air inlet, hold the trigger on the air tool and then flood the tool with the oil until it starts running out the air vent.
Then, put a rag around the air outlet to catch the spray and hook it up to air and operate the tool.

If you repeat this a couple of times you might not have to take it apart at all.

Some impacts come apart by removing the rear cover which is sometimes referred to as an end plate.

 

please don't use wd-40 in air tools it eventually dries to a sticky/hard layer inside the tool. atf works about the best of any thing you can buy for lubing cleaning internals on air tools.

murphy was an optimist

 

Pretty easy. Once I took everything apart, I just used some clean rags and wiped everything down, and then liberally used some air-tool oil on everything.

Works great now!

Here is the impact wrench. There are 3 allen screws holding the bell housing on to the handle/body.

Once you remove the bell housing. everything will just fall out, so be careful.

This shows what I guess is the end plate. Is that a zerk fitting on the back? I wonder because inside it looked like there was wheel bearing grease on the inside of this plate:



Here is a close up of it:



Here is what is inside the bell housing,





and here is what it looks like disassembled





Above the trigger, and before the bell housing, you have this cylinder that has blades that slip in and out of their slots. as air goes through the handle, it catches these blades and drives the spinning. The blades on the left if this pic slip into the slots of the cylinder on the right side of the pic.





You can't see it, but in the above pic under that disc, center page, there is a bearing. It was sort gummed up. I just blew it out with some strong air, and lubed it liberally with air-tool oil.

Below is another picture of the blades and cylinder



I didn't undertand it until I was putting it back together, but housing that this cylinder lives in is not a perfect fit. The housing is sort oblong, and this cylinder with it's blades fit tight up at the top, but loose at the bottom. So as the cylinder spins, when the blades are at the top of the wrench, they are fully retracted in the cylinder. But the at the bottom are slightly hanging from the cylinder so the air catches them.

My bet is that it was these blades not slipping in and out that was why the impact wrench wouldn't spin

Unfortunately, I couldn't get all of the wrench disassembled because behind the trigger, there was a allen screw that was starting to strip:




My only question aside how to use the 'zerk' fitting on the end plate is what is at the bottom of the handle, next to where you join the air hose attachment? It's got an allen screw and just slides out. Not sure what it's for. To add oil?

 

the end plate is actually that piece you speak of in pic #5 where you state there is a bearing in it.

the zirk is to grease that bearing

the screw at the base of the handle, not real sure. I'll have to do some looking.

 

now that I've taken apart the thing, I have a much better idea of what you are talking about here.

Thought what is meant by 'lap'ing the end plate?

 

So, that is what I thought about the zirk zerk fitting. But it doesnt' look like a zirk that I'd see on a car, for example. What sort of attachment would grease that fitting? And what sort of grease should be used?

 

it uses a needle type injector like this



as to the grease? again, not sure. It's been a long time since I rebuilt mine or even used them.

I do not know if your gun is actually an ingersoll rand but it looks like one. A 231 or one of the sub models to be more precise. if you researched IR 231, you will likely find a wealth of info that would be applicable to your gun. A lot of the knock-offs were actually 231's made by IR and relabeled by whoever. I think I have a Mac (like in Mac tools) that is actually an IR 231 also although it was not labeled as such.

plus I have a couple actual IR 231's and then I have a cute little 3/8's version of the same gun. Can't recall the model on that one.

strong guns.

 

thanks for the info!. I had no idea. Where the heck do you get those needle injectors. I've looked online at Lowes, harbor frieght, they don't seem to carry them.

 

Congratulations on getting 'er running again.

Strange place for a grease fitting though. Go light with the grease in there, I suspect the air blows it right into the motor, making things "sticky" in it. Sears usually has the needle you want in their automotive section.

 

Needle injector lubes rear bearing, Screw in handle is to put oil into wrench, Been years since I took one apart. I always just squirted oil down the air fitting

 

same here.


and yes, over greasing the rear bearing will give you a lot of grief. The excess will end up in the air motor and, at the least, reduce performance.

 

that's exactly why I didn't put in any grease, for fear of it being too sticky.

the nice thing about this design, though, is that the center spline? that everything revolves around is hollow up to the bearing. So, when the grease is inserted into that zirk fitting, the grease stays inside the spline. (theoretically, anyway).

 

any ideas on how to loosen that allen screw under the trigger? Maybe some pb blaster? I suppose if I had to I could drill it out, but that might be me being obsessive.