Suggestions for new garage compressor

[md21722]

I have air tools that draw 30-40 CFM and have to downrate compressor output about 26% due to altitude. 200 pounds is not as much as some. The Jenny U pump weights about 340 pounds and is rated for 7.5 HP at 610 RPM to produce 27 CFM @ 175PSI. At 10HP at 760 RPM it'd make 35.

 

[Finky198]

I tell you what next time I have the Ir 2475n7.5 runing I will check the ambient temp and 1st / 2nd stage temps and will post some data and see shall see

I really have seen no issues in the higher rpm system it like a gas vs diesel motor they are both reliable in today's day and in the end they both last a very long time...

About the water in the system on average
we see less than a 4oz in a 12hr day

 

[md21722]

That would be some nice data. I have an old dual stage Champion that runs around 175F. It only turns 700 RPM. My single stage Emglo's run around 320-360F and turn 1140 RPM. I'm thinking of replacing the Champion pump with a 2475 for more air. The flywheel of the 2475 is small enough it should fit just fine on the top plate of the tank. I don't have the clearance for a 16-18" flywheel.

 

[volaredon]

I bought a 5hp 80 gallon Emglo about 15 years ago for $500 and it has been about the best $500 spent for garage tools (besides my 2 post lift) It was used when I got it, out of the local paper, bought from private party, 4 cylinder V4 pump, 2 stage, and (don't remember exactly) but about 18ish CFM at 175 PSI. I have never "not" had enough air power for anything I have thrown at it// and just now am replacing the rings and valves in it after ALOT of hard use/// not counting what the PO did with it, what exactly that entails I don't know... other than it was a "backup compressor" in the P.O."s body shop til he retired... mine is a 1987 model (year) I'd be hard pressed to buy a brand new one if and when I have to replace it, I will probably lean on Craigslist for my next one.
Mine is the "W" pump. I see above that you make mention of a "U" Emglo/Jenny pump? I thought all of theirs with a "U" designation were "unloader" models made for a gas engine that stays running while the compressor starts/stops on account of a minibike style clutch on the engine....

 

[md21722]

The W/WU pumps are rated about 18 CFM w/ a 5 HP motor @ 175 PSI and weigh about 175 pounds. With a 5HP motor they turn 750-770 RPM.

The U pump is the next size up. It's rated 27,35 CFM @ 175 PSI w/ a 7.5,10HP motor and weighs 275-350 pounds. RPM is 610,760.

By the time you are up into the U and T pumps there is no constant run so no head unloaders like in the smaller ones.

The "U" in the KU or WU pumps references the head unloaders for constant run operation. In that case there is a pilot valve instead of a pressure switch. The pilot valve has a line to the head unloaders to hold the valves open when air compressor operation is not needed/its just freewheeling.

 

[jonjon1]

That would be some nice data. I have an old dual stage Champion that runs around 175F. It only turns 700 RPM. My single stage Emglo's run around 320-360F and turn 1140 RPM. I'm thinking of replacing the Champion pump with a 2475 for more air. The flywheel of the 2475 is small enough it should fit just fine on the top plate of the tank. I don't have the clearance for a 16-18" flywheel.

I have a brand spanking new 2475 on the crate, lol, actually I think I am going to keep it as a back up. The best way to buy the 2475 is on the 7.5hp 80 gal unit, you can sell the tank for $500 (with the pressure switch, plumbing, wiring, and guard) , the motor for $650, the starter for $125, and sheave and belt for $50, and have the pump for under $500 BRAND NEW!!! (just have to buy the 7.5 from zoro with a 25% coupon)...

You could make a job out of that lol, stripping and parting out that compressor on ebay, I seen pumps sell for $1100, motors for $750 (that weg is expensive), the tank you would have to sell locally, but I know around here for $500 that would be scooped right up by someone looking to build a compressor...

Figure someone buys that tank for $500 off of you, then a kellogg pump for $650, baldor 5hp motor for $275, and starter for $80 they have a nice unit for under $1500...
EVERYONE wins...