Air tools won't run - just vent

[sport1901966]

Hi All,

I am hoping someone may be able to offer some insight on some air tool issues I'm having.

I've got one of the ALDI (powercraft I think?) compressors, but I having trouble getting any effectiveness out of it at all.

I bought it with an impact gun and it always seemed a bit weak, I was always better off just undoing bits by hand.

My uncle then bought me one of the Snap-On MG750 impact guns, it was still quite weak, but at least the gun was ruled out as the cause. I was having trouble whereby the gun wouldnt always run, a lot of the time it would just vent the pressure without spinning, and when it did it was weak. I then looked in more detail at the gun requirements and it recommends a minimum hose diameter of 9mm. I have now bought some 10mm hose and after messing around with the fittings eventually got it hooked up.- I bought a couple of female quick couplers with male threads to go on the hose, only to find they are a different type to all the fittings I have with the compressor (based on screwfix listings the ones with the compressor are 'Universal' whereas the new ones where PCL i think). Unfortunately the tools are for the most part still just venting the pressure out the exhaust instead of running.

From what I have read I thought the Aldi compressor should be sufficient to meet my needs - I dont need to be running it a lot, just need a burst of power to undo suspension strut top mount nuts, run an airsaw etc. I'd have thought with the tank pressurised to 8 bar there should at least be enough flow for a short burst of high torque from the gun, but even then it'll tend to vent the pressure rather than run.

Its very frustrating as the compressor an tools are as good as useless at the moment. Have I got something set up wrong with the compressor? I have checked the oil, ensured the tools are oiled etc, otherwise I am at a loss!

Any advice/suggestions are much appreciated!

 

[rtbcomp]

Has it still got the original 1/4 inch BSP outlet on it? If so replace it with a 1/2 BSP one and get a 1/2 regulator and 10mm bore hose.

 

[shenion]

The stock regulator on many compressors tend to be real restrictive. That could be an issue.

Are you oiling the tools? Without oil, they will quickly loose compression. I have an oil fogger on the poty my tools run on. You can just add a few drops of oil to the air port of each time you use the tools if you don't have an oiler.

 

[Tman]

Sounds like oil issue I have used a mates powercraft compressor and impact gun and was quite surprised. So much so I went and got one not the impact gun but I think it is a sip rebrand, try bit oil in fwd and reverse.
You have made sure the little power setting wheel is on a setting and not stuck in the middle ie. between 1-2

 

[mike 109444]

It could be the vanes are sticking (still need running in) If the oil you have used is to thick then that will make them stick even more! Try some VERY thin oil and connect the gun directly to the coupling on the compressor (taking the hose out of the equation). If possible put it on a nice hot radiator over night to thin the oil already in there and take to compressor while still warm. Google rotary vane for an ideal of what's inside driving the shaft.

 

[outofthefire]

If your having problems with more than one air tool the problem lies with the compressor. My air tools vent straight to the exhaust when ever our compressor goes down at work, I'd take rtbcomps advice. The other problem i've found with aldi and lidl air tools is that they can be a bit hit and miss a few of us bought nut runners for screwing floors down and I would say half of them were useless while the other half performed great, so its possible that you've got a duff compressor. They've got 3 year warranty so it might be worthwhile taking it back and swapping it for another one.

 

[sport1901966]

Thanks all for the speedy and helpful advice.

It is with all the tools, I'd would almost term what they are doing as stuttering. If a tool isn't receiving enough flow/pressure will they just vent what little they are receiving?

They are a few different brands also; silverline air saw, Snap on impact gun, powercraft impact gun...

I have made sure to keep them oiled so hopefully that can be discounted as a cause.

I tried the test running them directly of the comp outlet, and whilst it improved, the stuttering was still present, I couldn't cut a thing with the air saw if I wanted to.

It does still have the original outlet/regulator on the tank, but I don't remember it doing the stuttering all the time I've had it. Is it possible the regulator has gone faulty?

 

[rikrobson]

What pressure does the compressor read? Does it vent Ok if you put on a tyre filler?

 

[sport1901966]

The compressor cuts out when the tank pressure reaches 8 bar (according to the gauge) and the according to the regulator gauge, the regulator does appear to be doing its job - although I could just be the gauge isn't keeping up with any fluctuations in flow.

Is this setup really man enough to be running air saws/high torque impact guns (supposedly - 9.5 CFM, 2.5hp, 24L tank) - obviously I am not expecting the compressor itself to keep up with them, but I was hoping at least when the tank is up to pressure it should give enough torque/running time to get some pretty tight bolts loosened at least, or make a good start to a cut with the air saw (at the moment I can't even get a cut started). I can't work out if the compressor is faulty, although the stuttering would suggest maybe it is? Or whether I am just expecting too much of it....

If I need to buy a new unit I am prepared t do so, but I don't want to waste money and discount a compressor that is capable of being up to the job. Although I do actually want to start working on the car at some point not the compressor all weekend!!

Thanks again for the help guys.

 

[anjum]

As said above try changing the regulator. Has the compressor got a non-regulated outlet on it or can you disconnect the regulator and try it form the tank directly? Is there someone nearby with a good compressor you can test your air tools on maybe the local tyre place?

 

[outofthefire]

Air goes in through the input and out through the exhaust if there isn't enough pressure then it wont spin the motor. I would say you've definitely got a problem with air delivery even a crap compressor should make the motor spin a bit.

 

[sport1901966]

It does have an unregulated outlet and the tools seem to do the same thing from that. Is it possible there is some sort of blockage between the tank and the outlets? I'll have a closer look and see if I can disassemble and inspect.

 

[Tman]

Could be your quick connectors I had a few of them go bad

 

[sport1901966]

Well I've been out and stripped it all down, other than build up of a small amount on the surfaces (certainly not enough to restrict the airflow in my opinion) it all seems clear from the tank to the regulated and unregulated outlets.

I then went back and tried out the aldi impact gun that I bought with the compressor and it seemed run ok, just a bit wimpy torque wise as was the case from the beginning.

It seems to exhibit the same issues with both outlets, is it likely that they both would have failed?

Could it just be the case that 24L of volume at 8bar cannot provide enough flow even for a short burst of sufficient torque to run the Snap-On gun or airsaw?

 

[ford34/2]

8 bar is about 116 PSI, which should be sufficient to run air tools for a very short period, now my next problem is 24L converts to less than a Cu ft, or
0.8475519977327999 cu ft.

now in the real world that will last a few seconds.
so what does the 24 L represent.???

I think you are asking a lot from the compressor you have, any mates or a friendly garage let you try their air supply?? then you can take your tools and eliminate them from the equation, I think you will find they are ok, your just lacking volume air supply, if you can maintain 116PSI I dont see a problem with pressure, just volume and possibly restriction through the fittings you are using.
Stan
snap on spec:
Specifications:
Sq. Dr. size, in.
................................................ 1/2
Rec. Air Press., PSIG,
(kPa)
................. 90
(620)
Air Cons, CFM, (SCFM) [l/min]
Free Speed
..................................
5.3 (38) [150]
Impacting
.....................................
4.2 (30) [119

I think you will find a Sabre saw wanting similar amounts of air, 5 Cu ft,at 90+ PSI continous

 

[brightspark]

what is the cutout pressure and what does it cut back in at . if for instance it cuts out at 120 psi and cuts back in at 90 psi does your air tools work between those settings. if not its restricted air supply on your fittings or bore of hose .

 

[octo0072000]

if it's only 24 litre tank it's not going to run air tools for more than a few seconds you need more volume
bigger tank etc to run a air saw for more than 20 seconds you need 150 litre tank 14cfm pump

this kind of size

http://www.ebay.co.uk/itm/Wolf-Air-...Air_Tools_and_Compressors&hash=item3a8a12ccb2

 

[Cobbler]

From what I've seen most air tools quote the air consumption at 25% usage, so 4cfm used continuously is about 16cfm.
Fine for occasional use for wheel nuts etc, but a saw or grinder will run it flat as you need to run it for longer periods. I bought a mini grinder quoted on the box at 4cfm, then read the paperwork inside which stated 16cfm continuous.

Cobbler

 

[marlinspike]

My Aldi 24l compressor claims 7cfm, but as mentioned many tools quote a minimum cfm which in the real world gives you power for about 2 seconds. The Aldi one won't run the sand blaster they sell with it (though didn't really expect it to tbh).

 

[sport1901966]

8 bar is about 116 PSI, which should be sufficient to run air tools for a very short period, now my next problem is 24L converts to less than a Cu ft, or
0.8475519977327999 cu ft.

now in the real world that will last a few seconds.
so what does the 24 L represent.???

I think you are asking a lot from the compressor you have, any mates or a friendly garage let you try their air supply?? then you can take your tools and eliminate them from the equation, I think you will find they are ok, your just lacking volume air supply, if you can maintain 116PSI I dont see a problem with pressure, just volume and possibly restriction through the fittings you are using.
Stan
snap on spec:
Specifications:
Sq. Dr. size, in.
................................................ 1/2
Rec. Air Press., PSIG,
(kPa)
................. 90
(620)
Air Cons, CFM, (SCFM) [l/min]
Free Speed
..................................
5.3 (38) [150]
Impacting
.....................................
4.2 (30) [119

I think you will find a Sabre saw wanting similar amounts of air, 5 Cu ft,at 90+ PSI continous

It certainly seems the compressor/receiver volume aren't up to the task of these tools. Testing on some other equipment is a good idea, I'll bring them into work to give them a go, thanks for the suggestion.

what is the cutout pressure and what does it cut back in at . if for instance it cuts out at 120 psi and cuts back in at 90 psi does your air tools work between those settings. if not its restricted air supply on your fittings or bore of hose .

It cuts in at 6 bar (84psi) and cuts out at 8bar (112psi). They work better - but they are still pretty useless even at this pressure - using the snap on gun and air saw for examples again, they both 'stutter', the gun may manage a few impacts, but seeming pretty weak ones, and the air saw will stop as soon as its put in contact with any material to be cut. Even when directly connected to either the regulated or unregulated outlets.

if it's only 24 litre tank it's not going to run air tools for more than a few seconds you need more volume
bigger tank etc to run a air saw for more than 20 seconds you need 150 litre tank 14cfm pump

this kind of size

http://www.ebay.co.uk/itm/Wolf-Air-...Air_Tools_and_Compressors&hash=item3a8a12ccb2

So it sounds like really I need to be looking at a compressor with the specification required to more or less run the tools directly, rather than just relying on the pressurised air in the tank, if I want to be able to use them for any length of time. It's disappointing how optimistically air tools/compressors in general seem to be sold - its one thing not being able to run a tool at its peak, but to not run it in any useful way at all is incredibly frustrating, when the specifications would suggest they should.

It does make me wonder what the point of these level of compressors are - if they cant run the kind of tools that give the use of an air compressor its unique benefits then it seems like a very large piece of equipment at a lot of additional cost for just pumping up tyres/blowing dust out... Maybe I'm missing the point but selling them alongside impact guns/air shears/air drills/blast guns seems a bit of a misrepresentation?

I think I would struggle to fit a 150L receiver in my garage, would the 90L version still be up to the job do you think?

From what I've seen most air tools quote the air consumption at 25% usage, so 4cfm used continuously is about 16cfm.
Fine for occasional use for wheel nuts etc, but a saw or grinder will run it flat as you need to run it for longer periods. I bought a mini grinder quoted on the box at 4cfm, then read the paperwork inside which stated 16cfm continuous.

Cobbler

Hmm it certainly seems that as with many other consumer items the 'headline' specifications have little relevance to real world use!

My Aldi 24l compressor claims 7cfm, but as mentioned many tools quote a minimum cfm which in the real world gives you power for about 2 seconds. The Aldi one won't run the sand blaster they sell with it (though didn't really expect it to tbh).

Seems like much the same experience I am having. They seem quite limited in what they can actually do, to a level where I would question whether having something the size and bulk of this specification of compressor is actually worthwhile over the electrically powered alternatives