Atlas Copco compressor

[herbiethemisfit]

Got a lead on an older Atlas Copco SF4 scroll compressor for a very good price. Has over 10,000 hours on it. Guy has been running it in his small CNC shop for the past 7 years. He is selling because he bought a larger compressor.

I currently have a ~25 gallon Husky compressor that is not heavily used. Mostly air tools when working on the vehicles, but I do occasionally do some media blasting and grinding and it definitely does not keep up. And it's louder than you-know-what.

I'm thinking this is pretty overkill for my needs but it's hard to pass up a scroll compressor at this price.

Anybody have experience with these older scroll compressors with a lot of hours on them? Am I crazy to want this thing?

 

[930dreamer]

Is it single or three phase power?

 

[SGKent]

I would make the assumption that the scroll will be worn out soon. Price out and find the availability of the scroll. If they are NLA then consider that. I bought a used twin cylinder craftsman made by devilbiss for about $200 then changed the filter and lowered the air pressure to something less stressful on it. It needed a motor too so the whole cost was about $300. I put that with the other one like it I had, and ran a line between the two tanks. Now I have a 4 cylinder 45 gallon compressor for a total cost of about $600 that will keep up with anything I throw at it. Single phase 240 (or 120 if I want to go back to that). There are other options out there if you look. 10000 hours is 3 hours a working day running time for 10 years. 75% to 95% of that scroll life is used up.

 

[herbiethemisfit]

The motor has been swapped out to a single phase, 240V, 5HP motor. I believe he also replaced the starter to accommodate the 3-phase to single phase conversion.

They still make this series compressor, so I'm guessing parts would be available. Dug around their website, and they do offer a service kit for it but can't find a price on it.

 

[SGKent]

The motor has been swapped out to a single phase, 240V, 5HP motor. I believe he also replaced the starter to accommodate the 3-phase to single phase conversion.

They still make this series compressor, so I'm guessing parts would be available. Dug around their website, and they do offer a service kit for it but can't find a price on it.

I'd consider making some calls to see what is in the kit and what price. If I bought the unit I would probably buy a kit and stash it once I determined that the unit would meet my needs. That way you have the parts before they go NLA. Some of this stuff cannot be replaced once it goes NLA, and it is always a shame to lose a good piece of equipment over replacement parts. The scroll on our AC unit went out after 15 summers and it was hard to find someone who would replace it. But the cost of $2,000 in repair parts and labor was certainly a lot less than the cost to replace the whole system ($15,000 - $20,000). Had I anticipated the repair sooner before the scrolls became scarce, it might have only cost $900 parts and labor. In your situation there is no charging, carrying off old refrigerant etc., so you should be able to repair it just for the parts cost when it wears out.

 

[Jvvmusme]

the theory says that the scroll unit never touches so the scroll unit should never wears out and therefore never has to be replaced

 

[LS6 Tommy]

the theory says that the scroll unit never touches so the scroll unit should never wears out and therefore never has to be replaced

The seals wear.

Tommy

 

[koditten]

10k isn't a lot of hours for a scroll compressor. If its not leaking oil, its good for a lot more hours that that.

I maintain machines with 70,000 hours...and I know those Hobbs hour meters have rolled over at least once.

 

[Jvvmusme]

The seals wear.

Tommy

correct !!!

but changing seals is easy and cheap

 

[purediesel]

I would stay away from this style compressor if you aren't going to have a load on it most of the time. A friend of mine had one as an automotive hobbyist and the screws built up condensate and pitted the screw faces and also ate a bearing. Had it rebuilt and got rid of it because the repair costs. Could have been a isolated case, but still something to note.

 

[LS6 Tommy]

I would stay away from this style compressor if you aren't going to have a load on it most of the time. A friend of mine had one as an automotive hobbyist and the screws built up condensate and pitted the screw faces and also ate a bearing. Had it rebuilt and got rid of it because the repair costs. Could have been a isolated case, but still something to note.

A screw compressor is a totally different animal from a scroll.

Tommy

 

[purediesel]

A screw compressor is a totally different animal from a scroll.

Tommy

Thanks, didn't know that. Guess I have some research to do.

 

[MacMcMacmac]

Copco parts are notoriously expensive. Look before you leap.