I have some cmans promo air tools I got with my cmans 30 gal compressor several years ago. It is supposed to deliver 6.4 cmf at 90 psi. I have it set to 90 psi on the built in regulator. These air tools have never been real impressive at delivering torque. I bought an earthquake impact that should have run circles around that cman. It barely removed my lugnuts. I'm kinda thinking that I'm just not getting enough airflow. Is there a way to measure the cfm output? Maybe I am using the wrong fits/hose/couplings? The fittings are 1/4 npt and 50ft cambelhausfield hose from wamart. Sorry for the dumb questions lately.
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whats wrong with my compressor?
- Thread starter monster1
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kartracer55
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People are going to start blaming the fittings. Ignore them.
What is the ID of the hose you are using first of all?
What is the ID of the hose you are using first of all?
Outlawmws
Well-known member
People are going to start blaming the fittings. Ignore them.
What is the ID of the hose you are using first of all?
And how long is it?
91bronc300
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It's not so obvious but the reverse/forward switch on those earthquake impacts is also a torque setting switch. I don't know if you've missed it or not, but if you look close on one side you can see that it's marked 1 through 6. It might just be set low. You don't need large CFM to get full force from an impact only full air pressure. You only need CFM to keep the gun running long which you don't usually need to do. I use a small Porter Cable pancake compressor to run my 1/2" earthquake. It'll spin lug nuts off no problem.
rsanter
Well-known member
Some of those cheaper little compressors from CMan have some crappy little regulators
Bob
Bob
It's not so obvious but the reverse/forward switch on those earthquake impacts is also a torque setting switch. I don't know if you've missed it or not, but if you look close on one side you can see that it's marked 1 through 6. It might just be set low. You don't need large CFM to get full force from an impact only full air pressure. You only need CFM to keep the gun running long which you don't usually need to do. I use a small Porter Cable pancake compressor to run my 1/2" earthquake. It'll spin lug nuts off no problem.
The hose is a 3/8" 50 ft Campbell hausfield. The earthquake must be a new model. It has one dial on the back of the gun. The selector has one large dot in the reverse and small medium and large for the forward. I was really hoping it would be as simple as me not knowing.
Edit: I see you have the newer one. Keep in mind the 1st setting (forward) is very light and in some cases doesn't even work on my gun. You have set it in reverse, correct? I know it sounds dumb just making sure we are on the same page.
The 6.4 CFM rating of the compressor is just the pump output. The compressor itself will put out as much as you can let out of the tank at once.
I use 3/8" hose with 1/4" NPT fittings and my newer Earthquake is bad *** coming off my Craftsman compressor. Although I have the pro compressor which came with a little bit better regulator, it might be your regulator.
Running regular 1/4" NPT connections and 50' of 3/8" hose you are losing roughly 15-20 psi give or take. I set mine at roughly 110 psi.
This is the older one but you can see it pulls crank pulleys off in no time flat.
The 6.4 CFM rating of the compressor is just the pump output. The compressor itself will put out as much as you can let out of the tank at once.
I use 3/8" hose with 1/4" NPT fittings and my newer Earthquake is bad *** coming off my Craftsman compressor. Although I have the pro compressor which came with a little bit better regulator, it might be your regulator.
Running regular 1/4" NPT connections and 50' of 3/8" hose you are losing roughly 15-20 psi give or take. I set mine at roughly 110 psi.
This is the older one but you can see it pulls crank pulleys off in no time flat.
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Edit: I see you have the newer one. Keep in mind the 1st setting (forward) is very light and in some cases doesn't even work on my gun. You have set it in reverse, correct? I know it sounds dumb just making sure we are on the same page.
The 6.4 CFM rating of the compressor is just the pump output. The compressor itself will put out as much as you can let out of the tank at once.
I use 3/8" hose with 1/4" NPT fittings and my newer Earthquake is bad *** coming off my Craftsman compressor. Although I have the pro compressor which came with a little bit better regulator, it might be your regulator.
Running regular 1/4" NPT connections and 50' of 3/8" hose you are losing roughly 15-20 psi give or take. I set mine at roughly 110 psi.
This is the older one but you can see it pulls crank pulleys off in no time flat.
Thanks. You've given me some good suggestions. I have a pressure gauge somewhere in my garage. Ill see if I can rig it up to the end of my air hose. May be a simple as cranking up the regulator to get 90 psi at the end of the hose or changing out a bad regulator.
Thanks. You've given me some good suggestions. I have a pressure gauge somewhere in my garage. Ill see if I can rig it up to the end of my air hose. May be a simple as cranking up the regulator to get 90 psi at the end of the hose or changing out a bad regulator.
I don't know if you can get a truly accurate reading based on a few reasons. 1) Static pressure is different than dynamic pressure. That is to say, setting at 90 psi, the hose should fill up to 90 psi regardless of length and connections. 2) The venturi effect on pressure gauges might make the readings appear off. That is to say as air flows thru the gauge the readings are inaccurate. By how much and which way I do not know.
What you can figure out is with charts, average pressure loss over ** distance with 3/8" hose, and average pressure loss thru 1/4" NPT couplings. Milton has some examples.
Here's some charts:
3/8" hose w/ 50' 100 psi loses 4.1 psi @ 20 CFM (your impact is pulling in that neighborhood). Interestingly enough according to that site air hose is better than pipe as far as friction goes (I didn't know that).
QC at compressor hookup and then again at tool hookup (2x)
https://miltonindustries.com/uploads/Milton_2011_Catalog_Pg_35.pdf
Looking at a 6-7 psi drop for each one, so 12-14 psi for the two.
So you are down roughly 16-18 psi from what your regulator is set at, assuming your regulator can even flow 20 CFM @ 90 psi. If it's a smaller one, it might have trouble. I do not know if you should set your regulator at dynamic pressure or static pressure. I split the difference and set it at 110-115. This gives good performance with my Earthquake and other air tools.
In the future, I'm going to upgrade to a 3/8" regulator and 1/2" hose and 3/8" quick connects for my Earthquake and run a separate line for 3/8" hose w/ 1/4" fittings for all my other tools.
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Edit: I see you have the newer one. Keep in mind the 1st setting (forward) is very light and in some cases doesn't even work on my gun. You have set it in reverse, correct? I know it sounds dumb just making sure we are on the same page.
The 6.4 CFM rating of the compressor is just the pump output. The compressor itself will put out as much as you can let out of the tank at once.
I use 3/8" hose with 1/4" NPT fittings and my newer Earthquake is bad *** coming off my Craftsman compressor. Although I have the pro compressor which came with a little bit better regulator, it might be your regulator.
Running regular 1/4" NPT connections and 50' of 3/8" hose you are losing roughly 15-20 psi give or take. I set mine at roughly 110 psi.
This is the older one but you can see it pulls crank pulleys off in no time flat.
this morning i went to the garage to try and see how much air that impact is using under load. the regulator gauge dips down 10 psi when i pull the trigger under load so i cranked the regulator up to 100psi. by under load, i mean having a 32mm socket on the gun while i grip it with my left hand. i am able to hold onto the socket tight enough that it doesn't spin just rattles the **** out of my bones! i watched your youtube video and your gun took that pulley bolt off like it was nothing. when i used my gun on lug nuts yesterday, it just sat there sounding like a tommy gun and not budging the lug nut. btw, nice shop "shoes!"
91bronc300
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I would go to harbor freight and tell them to switch your gun out for a new one.
trboxman
Well-known member
I can't hold my EQ from spinning by hand, I don't think you should be able to either.
Man, I really don't know what the hell is going on with this thing. I bought a new regulator from HF (I know). Got up to 150 psi and the damn thing s topped working. I pulled the bleed valve to empty the tank and got hit with little fragments of what I assume is dried thread compound. I took the regulator off and put the old one back on. I fired up the compressor and waited for pressure to build up. I adjusted the regulator to 110 psi to account for the pressure lose. Hit the trigger on the impact gun and again can hold the socket from spinning. The impact wont even function on the low setting. The gauge went from 110 down to 80 and then up to 90 after I let off the trigger. I've been reading some of the reviews online on similar cmans commpressors and some complained of the same problem.
I went out today and bought a 3/8" regulator. Set it at 120 psi it dropped to 60 psi! No joke. No power off my impact even at 120 psi. I'm pretty confused!
Rebuilt my old 1/4" regulator and set it at 105 psi and it drops to 90. Works better than before. The spring inside gets rusty and the o-rings start to wear out and leak. I'd tear into it and see what is going on.
Home Depot has a $20 1/4" air regulator under the Husky brand that will do 26 CFM @ 90 psi w/ a 5 psi pressure drop. That would be adequate for any of our needs. Lowes has one that looks similar but it's made in China, the Husky is made in Taiwan, and to me felt a little bit nicer.
Don't buy any regulator from Harbor Freight. They are cheap and leak. Spend another $10 on a decent one.
Rebuilt my old 1/4" regulator and set it at 105 psi and it drops to 90. Works better than before. The spring inside gets rusty and the o-rings start to wear out and leak. I'd tear into it and see what is going on.
Home Depot has a $20 1/4" air regulator under the Husky brand that will do 26 CFM @ 90 psi w/ a 5 psi pressure drop. That would be adequate for any of our needs. Lowes has one that looks similar but it's made in China, the Husky is made in Taiwan, and to me felt a little bit nicer.
Don't buy any regulator from Harbor Freight. They are cheap and leak. Spend another $10 on a decent one.
Try bypassing the regulator, and run your impact straight from the tank. Then you can find out if the regulator is the bottleneck (it probably is, the question is how bad), or if something else is going on.
Sure, airguns are usually rated @90 psi but are frequently run at higher pressure. "Typical" shop system (at least over here) is run directly from the tank @8 kg/cm² ~115 psi, even higher.
Sure, airguns are usually rated @90 psi but are frequently run at higher pressure. "Typical" shop system (at least over here) is run directly from the tank @8 kg/cm² ~115 psi, even higher.
rodknocker
Well-known member
Did you verfiy you gun works good on another compressor?
I'm going to my friends house today to test this gun. I returned the first one yesterday. They exchanged it but looked at me funny cause they said they never had an earthquake. Impact gun come back and the local guys beat the **** out of them in the oilfields.
truckdriver
Well-known member
I never run a regulator with impact. My buddy's compressor is 175psi non regulated and the impacts run great.
tpolley
Well-known member
same issue here. here's my setup:
150psi compressor
3/8 filter/regulator
3/8 fog lubricator
100ft hose reel
100ft 3/8id 1/4npt hose
there's a 12ft 3/8 hose in there somewhere.
i use reducers at the regulator to go from 3/8id to 1/4id fittings on the hoses. the quick couplers are all 1/4id. the regulator and oiler don't leak.
anyway, my setup does the exact same thing yours does. i have to set the regulator to 120psi to get it to drop to 90psi when i hit the IR2135 impact. its fine but its weird that it starts out really fast then slows down to normal operating speed.
150psi compressor
3/8 filter/regulator
3/8 fog lubricator
100ft hose reel
100ft 3/8id 1/4npt hose
there's a 12ft 3/8 hose in there somewhere.
i use reducers at the regulator to go from 3/8id to 1/4id fittings on the hoses. the quick couplers are all 1/4id. the regulator and oiler don't leak.
anyway, my setup does the exact same thing yours does. i have to set the regulator to 120psi to get it to drop to 90psi when i hit the IR2135 impact. its fine but its weird that it starts out really fast then slows down to normal operating speed.
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Did you verfiy you gun works good on another compressor?
I went to his house and he has a huge kobalt dual stage that puts out over ten cfm's. Put the gun on the hose, grabbed the socket and pulled the trigger .. same thing that I'm able to keep the socket from spinning but it seemed to hit just a little harder but not much. I changed my regulator out today and that didn't help. I've come to the conclusion that I'm just expecting too much from a portable compressor and an inexpensive impact gun. If the tire shop guys use heavy duty stuff to put the lugs on then should I expect to loosen lugs with my gun? But if I torque my lugs by hand with torque wrench, I still can't get them off with my gun. I guess this is just the way it goes. Maybe I should stop obsessing about it and find something else to worry about like the grips on my different sets of pliers not color matching. LOL
I think you are getting the power we all are. I can stop a socket from spinning as well. I guarantee if you hook up a 2135timax it will have less power than the Earthquake.
I can't believe if you are truly putting 100 ft-lbs or so lugs on it won't get them off. It creams them. There must be something else at play here.
I can't believe if you are truly putting 100 ft-lbs or so lugs on it won't get them off. It creams them. There must be something else at play here.
I run an earthquake (old version) on a 5.8 cfm 20 year old compressor and it will most definitely break fasteners torqued to 120 lb/ft. The compressor is a portable with a built on regulator, so I run it with just a hose and quick disconnect coupling on the business end.
I add a couple of drops of oil to the earthquake every time I use it, right after I pull the drain valve to clear any water.
The portable has a small tank (maybe 10 gallon ?). I set PSI to 125, let it fill until it shuts off, pull the drain valve a couple of times and go.
When I pull the trigger on the earthquake, the regulator drops from 120 psi down to 80 +/- but the compressor keeps up OK with the gun. I don't have any applications where I need to run the gun more than maybe 2-3 seconds as it breaks anything I've put it on in no time flat.
I add a couple of drops of oil to the earthquake every time I use it, right after I pull the drain valve to clear any water.
The portable has a small tank (maybe 10 gallon ?). I set PSI to 125, let it fill until it shuts off, pull the drain valve a couple of times and go.
When I pull the trigger on the earthquake, the regulator drops from 120 psi down to 80 +/- but the compressor keeps up OK with the gun. I don't have any applications where I need to run the gun more than maybe 2-3 seconds as it breaks anything I've put it on in no time flat.
That is strange. I never tested my impacts by seeing if I could stop the socket from spinning but even when I had my 20 gal Craftsman compressor using my old IR2131 I could remove crank pulleys & axle nuts off Hondas at home. The only time I couldn't remove a lugnut with the IR2131 when working in the shop is when they were stripped or cross threaded. Then I would have to use the shop's 3/4 BluePoint gun which ended up having the replaced the wheel stud after getting the lugnut off.
I think you are getting the power we all are. I can stop a socket from spinning as well. I guarantee if you hook up a 2135timax it will have less power than the Earthquake.
I can't believe if you are truly putting 100 ft-lbs or so lugs on it won't get them off. It creams them. There must be something else at play here.
I agree that something just isn't right. I'm at a loss as to what it is though. The only thing I can think of now is to take the entire set up to a pneumatic repair shop up the street and pay them to check it out.
Well, I think I have it figured out. Taking into account that the shop that probably runs its compressor unregulated or cranked up put the lugs back on my vehicle, how could my compressor set at 90 psi take them off? I figure that with my length of hose, reel, fitting etc that I'm losing 15-20 psi at the chuck on the tool end. I'm also losing about 20 psi on the regulator when I pull the trigger on my impact gun. So what the hell, I cranked the regulator up to 140 psi and hooked up the gun. This things hitting hard now! Problem solved!