Question about Chicago Pneumatic 1/2" Air Impact Wrench

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My 1/2" CP air wrench just blows air thru when I pull the trigger

I worked fine for years, I always kept it oiled, now it just blows air thru when I pull the trigger, does not turn. Thanks, Doug

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I have ran into this many times, even though you keep it oiled dirt can and will get inside. what you need to do is unscrew the 4 alen head bolts and pull the nose off. You will see a shaft that looks kind of like a crankshaft with 5 or 6 flat carbon fiber plates sitting loosely in groves around the shaft. pull those out and clean them with solvent and check them for damage or wear. clean the inside of the gun with solvent or brake cleaner, reassemble and it should work fine. If the plates need replaced then you should be able to order them from a tool supplier,and they are not that much.

Posted on Jan 17, 2009

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My air gun has oil coming out from the front back switch it looks like transmission oil same color can anyone help &my trigger stays stuck never used it bought a rebuilt. WHAT A MISTAKE THAT WAS!im a...

A guy who owns an air wrench is probably a mechanic?

No reason to despair then because the parts and seals for most air tools are readily available along with exploded drawings. Apply a little patience and time and you can refurbish your own air tools when they need it.

There is often some oil escaping from the hammer gear housing of an air wrench that has done some work and transmission fluid is ok to use there. It was probably overfilled.
Good air motor oil can also red and there is a type with an antiseptic sort of a smell. If the motor is getting enough oil there will always be some being blown out of the exhaust port and depending where the port is depends where the oil ends up.

An air tool if it is being cared for properly will have a spoonful of air motor oil dribbled into the air inlet followed by a brief press of the trigger at the end of each day unless it is being used with an automatic oiler.

Air tools should also be used with a moisture trap in the airline and if they aren't (and even sometimes if they are) the first thing to suffer is the trigger return spring which also holds the valve on its seat. I suggest you buy a couple and fit one though if you only recently bought it you might as well tell the refurbishers to fit you one free of charge.

Good luck!

Feb 04, 2015 | Air Tools & Compressors

1 Answer

Air Impact Wrench leaking air at trigger.It`s a power craft and only cost 30 euros

Almost all impact wrenches will start leaking air and get weak. When this happens you just have to take the back off pull out all the pieces and thoroughly clean the dirty oil that turns to a solid and gets all over everything. There are not many parts so it's easy. Most important are those fiber fins that are loosely in the slots on the drive shaft. When the tools turns those come out of the slot and hold air so it turns with force. This part is sort of like a Wankel engine. When the oil turns to gunk the fins get stuck and don't come all the way out and air goes around them so the tool gets weak. Just clean everything, start with rags and use a toothbrush and qtips so everything is clean. Put it back together with new oil. Most of the time if the gasket on the back plate is leaking it's just dry so oil the seals. Put it back and it will be like new.
Don't use brake cleaner because it will destroy the seals and bearings. Always use a tire iron after to make sure your lug nuts are tight until you know the wrench is up to full strength.

This is a really easy job.

Nov 08, 2011 | Air Tools & Compressors

1 Answer

Model 734 1/2 in impact.wont blow air ,wont rotate,no tension on trigger.feel like problem may somehow be in trigger housing....

Yes, if you take it apart you'll find that the trigger isn't allowing air to pass through to the veins of the impact wrench. It's a relatively simple mechanism, where maybe something is broken inside.

If it were blowing air but the veins were stuck, I would say, lubricate it. But, if no air goes through it at all, then the trigger housing houses the problem part.

Have you tried to disassemble the air wrench?

Jan 21, 2011 | Chicago Pneumatic 1/2" Air Impact Wrench

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Wont work in remove direction just blows air

fill it wit oil hold in triger and flick between forard and reverse should free up the vains inside

Jun 29, 2010 | Craftsman 1/2" Impact Wrench

1 Answer

Craftsman 1/2 inch impact wrench,not working

Make sure you have at least 90 pounds of air and if you do you need to oil the wrench air tool oil pour some in the where the air line hooks up ..air tools need to be oiled daily cause compressed air cause water vapors to build up when you use it and then when it sits it begins to rust a bit and the oil stops this ...

Nov 14, 2009 | Craftsman 1/2" Impact Wrench

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Throttle valve is rotten and tool runs when you plug in the air without pulling trigger

there is a neoprene O ring in the trigger area ,that breaks down ,it needs a service by an air tool repairer ,it is not expensive. dont use wd40 or the like if dont have airtool oil use auto transmission fluid and this wont happen too often

Oct 18, 2009 | Craftsman 1/2" Impact Wrench

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Lack of power

the golden rule from i/r ,shinano,and all the air rattle gun manufacturers DONT USE WD 40 OR ANY OF PENATRINE TYPE PRODUCTS.for preference only use auto trnsmission oil if you arent prepared to buy air tool oil. If you brought the tool to me for a diagnosis and or repair,I would tell you that there is a small neoprene O/ring up in the trigger area that gets hard and starts to break up,giving those exact symptoms. those kero based products spoken about, exacebate the problem and often are the cause of the O/ring be coming hard in the first recommendation is to take it an airtool service centre ,it wont cost all that much(australia about $75 give or take) I agree with the dog ,good tools are worth looking after.No offence meant, just many years of experience

Aug 16, 2009 | Ingersoll Rand 236 1/2" Air Impact Wrench

2 Answers

It does nothing

Make sure that you have at least 50 psig of air pressure before you attempt to troubleshoot your impact. 70 is better, 90 is perfect. Impact wrenches are powered by internal sliding vanes, which can sometimes stick. There are a couple of ways to get it going again. Try 1 before going to 2, etc,:
1. Spray W-D 40 or a similar oil into the impact, while you are holding the trigger down. Give it a good shot. Connect the hose and pull the trigger. Tap the sides of the gun with a plastic hammer to help free up the vanes. Repeat. Normally, this is enough to get you back running.
2. Place it in a bucket and cover the gun with W-D 40. Work the anvil end and trigger to work the oil deep into the gun. Ley it soak 1 hour, and repeat the process, working the oil in, and the air out. Remove it from the oil, and drain the oil back into the bucket by holding the trigger down. Hook up the air, and blow it out.
3. Remove the cover on the head that covers the vanes. Make sure that the vanes will slide freely, and that all gaskets and "O" rings are in good condition. If you note any dry areas in the inner parts of the impact, lubricate with W-D 40, and reassemble.
4. I'm all out of ideas.. If that didn't fix it, I'd go get a new one.
Best of luck, --W/D--

Aug 13, 2009 | Air Tools & Compressors

1 Answer

No pressure when pulling trigger, trigger sticks in handle body

if air sound comes out when you press trigger your pressure regulator pin is stuck-oil gun and attach hose repeate until pin frees or remove pin and clean with brake kleaN oil and replace

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1 Answer

Just blows air when trigger is pulled.

Dave The rotor is too tight on the plate. Tap shaft with fiber mallet to open the clearance

Apr 07, 2009 | Impact Ingersoll-Rand 1 Inch Heavy Duty...

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