Air Compressor

[1994IDI]

Hey yall, I know this probably isn't the right forum to post this in, but I've come to trust a lot of people's opinions in this forum, and I don't know the cats in the other forums.
I am looking at buying a used air compressor. Craftsman, Model# 16640. It is only a couple months old, and still has the break in oil. so the guy says. he lives about a half hour away, but his wife works closer and will bring it my way.
I will be using it a couple times a week, and would like to know if it has more than enough power to whip the lugnuts on and off my truck with plenty of torque, and if it will be LOW maintenance. Judging by the stats below, what do you guys think?
He wants $150 which I think is a little high. I think he will come down a bit.

Description from Sears:

2.4 SCFM @ 90, 3.7 SCFM at 40 (125 PSI max). ASME certified vertical tank. Designed for job-site mobility. Cast iron pump cylinder. Direct drive oil lubricated pump. ASME approved safety valve.

SCFM Delivery:
SCFM Delivery At 40 psi: 3.7 SCFM
SCFM Delivery At 90 psi: 2.4 SCFM

Tank:
Compressor Tank Capacity: 12 gal.
Maximum Compressor psi: 125 psi
Compressor Tank Pump Style: Oil Lube
Compressor Tank Type: Vertical portable

 

[Shadetreemechanic]

check your tools. Most impact wrenches need at least 6 cfm. Many need more.
My 4.4 cfm compressor has to rest between wheels to run my 1/2 drive impact wrench.

 

[OLDBULL8]

It might whip the 1st 2 lug nuts off, then wait for pressure build up. Air compressors don't have power, your size of impact has the power. Compressors have CFM and pressure. That compressor is good for blowing up tires and the dust off tables, and very small air tools. Check out TSC or Harbor Freight.

 

[oldmisterbill]

Think of air kinda like electricity or water all 3 have something in common. Amperage-is to electricity as volume is to water or air -without amperage ,the pressure or voltage to do hard work like starting a big motor,hitting a starter on a low battery for a split second it spun then slowed down till you had nothing,-impacting an air hammer or,- shooting a long stream of water won't happen pressure gives the snap to start a bolt loose or if you remember spraying out of a partially closed garden hose -at first the stream was fast and far -but then fell short quickly, that is because the voltage didn't have the amperage backing it up to keep the power or voltage up enough to do the job. The air or water didn,t have enough volume to maintain the pressure to shoot the stream of water very long,or keep hitting the impact wrench to loosen the bolt,since there wasn,t enough volume to keep the pressure up.
So as previously said you need to know how much pressure and volume you need to do the job.
I hope I made sense in this explaination please correct or add thoughts if necessary.

 

[1994IDI]

You are making sense here. But are you referring to the amperage as the volume in the air compressor, or the scfm the air compressor produces?

 

[Shadetreemechanic]

amperage would be cfm.

 

[1994IDI]

Thanks a lot. I need a bigger compressor.

 

[Shadetreemechanic]

impact wrenches are air hogs. Do a little window shopping for the tools you want to run, then size your compressor to your tools. Most tools list the cfm requirements on the box or in the catalog.

 

[bbressler]

I got it's big brother. 16770, it's weak. I can get 8 nuts off, and have to wait.

 

[1994IDI]

Thanks for all your help guys. I picked up a Campbell Hausefeld. 15 gallon, 125 psi, direct drive, oiled. Over 4 cfm at 90 psi. Ran it last night, and think I will be satisfied.
Thanks for all your help.