Electric motor to drive compressor?

[freepowder]

I've got this old air compressor that runs on a 110v motor that weighs about twelve thousand pounds. I'd like to convert it to 12v and use it for on-board air.

What sort of 12v motor would be adequate to turn the compressor?
Preferably about 11,990 pounds lighter. Thanks.

 

[GeologistFelix]

The only thing that really puts out serious torque, is relatively common, and runs on 12V, is a starter motor, and they don't like to run continuously. A smaller 12V winch motor might work better, but they're harder to find and/or more expensive than an old starter. You wouldn't need anything like the 3-5hp motor in a proper 8-10k winch, though. Something from a 1200LB winch would probably have plenty of horsepower, but I don't know how much you'd spend on it, compared to getting a 12V compressor.

I wonder if you could plumb a little radiator into a starter motor to keep it from overheating, or fill it with holes and blow air through it with a strong fan...

 

[rusty_tlc]

Look at the HP rating on the electric motor, I think you will find that a comparably rated 12V DC continuous duty motor will cost more than buying a Viair or other 12V compressor.

 

[TS888]

Why not just mount it so it will run off a belt from the engine?

 

[Cpalmer]

I work in a motor shop and I agree with everyone else, a 12 volt motor to pull that compressor would probably not be feasible. Plus, the amp draw of a motor like that would require two large high amp alternators and two batteries. To me the best air compressor setup would be an old Chrysler air conditioner pump. They were about the size of a twin cylinder air compressor pump, and probably decent CFM! And you can switch it on and off via the electric clutch.

 

[freepowder]

Why not just mount it so it will run off a belt from the engine?

Thought about that but it would need an a/c clutch on the pulley and I don't know if I'm capable of engineering that. There would be some serious fabrication involved in mounting too.

 

[Leona74]

The only thing that really puts out serious torque

 

[freepowder]

I work in a motor shop and I agree with everyone else, a 12 volt motor to pull that compressor would probably not be feasible. Plus, the amp draw of a motor like that would require two large high amp alternators and two batteries. To me the best air compressor setup would be an old Chrysler air conditioner pump. They were about the size of a twin cylinder air compressor pump, and probably decent CFM! And you can switch it on and off via the electric clutch.

I'm getting that. I guess that compressor needs to be portable and run nail guns and such.

Who made the Chrysler A/C? How old? Model year?
Would the Chrysler fit in the hole where the smog pump is now?
Does it lube via a crankcase or need to be oiled through the air?
How hard would it be to adapt an a/c clutch pulley to something else, like that compressor in the pic?

 

[Elbert]

Look for an old York compressor...there are a number of writeups on the board.

I don't think there is a reasonable motor solution that would work for the compressor mentioned in the 1st post.

 

[freepowder]

Look for an old York compressor...there are a number of writeups on the board.

I don't think there is a reasonable motor solution that would work for the compressor mentioned in the 1st post.

Will a York fit where the smog pump is?

 

[rusty_tlc]

York is not the only option.

Grungles Homepage

I have a Sanden and someday I will figure out a mount for the 2F, I suspect it would fit where the smog pump is but it would be tight. I think it would work better piggy backed on the alternator.


Meanwhile Spressomon has actually installed a Sanden on a 100 series LC.

 

[freepowder]

York is not the only option.

Grungles Homepage

I have a Sanden and someday I will figure out a mount for the 2F, I suspect it would fit where the smog pump is but it would be tight. I think it would work better piggy backed on the alternator.


Meanwhile Spressomon has actually installed a Sanden on a 100 series LC.

Agreed my exisiting compressor isn't going to work.
But, found these:

Product : Extreme Outback
VMAC | Products | VMAC Products

The Extemeaire looks like a modified Sanden. So effectively you're pay for someone doing the lube and other mods. Retail $415 +/- Looks like it would be close to a bolt in installation w/8 mounting ears.

The Vmac looks to be their own design, correct me if I'm wrong. I'm thinking it's pricey as they're very coy about mentioning price. They also have a hydraulic-driven compressor. There are other hydraulic compressors out here as well and that would seem an elegant solution to mounting issues. Again, no price info without a 'quote' which screams $$$$.

 

[freepowder]

Thanks all for your input. Wish I coulda made that old compressor work, but alas.
What I think I'm gonna do is buy me an Extremeaire V-belt compressor--all the hard work's done on that 'un and it comes with a warranty.

Thanks again!

 

[Kurtis]

How many amps is the AC motor pushing it now? By the looks of it (looks fairly small) you could probably get an inverter off ebay for cheap and run it AC just fine. I can run a compressor much larger than that off my inverter and a couple deep cycle batteries in my race trailer.

 

[rusty_tlc]

How many amps is the AC motor pushing it now? By the looks of it (looks fairly small) you could probably get an inverter off ebay for cheap and run it AC just fine. I can run a compressor much larger than that off my inverter and a couple deep cycle batteries in my race trailer.

The surge current to start an AC motor usually exceeds the running amps. Looking at the physical size of the starter caps on that motor, I'd say the starting amps draw could be significant.

 

[TS888]

Will a York fit where the smog pump is?

No, a York is quite big. About the size of the compressor in your original post. Which I still think could be run off the engine.

 

[ntsqd]

It has pumped air

but not for very long. Got it to this point about 3 years ago and kind of lost interest. Current plan is to revisit it and possibly put it on the CTD.

That is the Chrysler V-twin A/C compressor. It's all iron, so a York is considerably lighter. Unlike the York it can't be mounted any way but 'V' straight up as it has a bolt-on cast aluminum oil sump with a crank driven gerotor oil pump. York's are splash lubricated. Displacement is something like a cubic inch bigger than the biggest York. The fabricated flange most easily seen is discharge, I think. Suction is opposite it. Details of how I made the coupling inside the tube, as well as all the rest of it, is the topic of not yet dead magazine article.

 

[lovetoski]

SOR has had rear PTO's from time to time, not too expensive. Plenty of torque to drive that compressor. Last time I checked, they were less than $200, but fabbing linkage, and connection to your compressor would be extra...(of course this would be super cool too...)

 

[jc43089]

Check out my writeup for some ideas that may help. I used the factory A/C one and it works fantastic. https://forum.ih8mud.com/60-series-wagons/586422-c-compressor-board-air-writeup.html

 

[freepowder]

SOR has had rear PTO's from time to time, not too expensive. Plenty of torque to drive that compressor. Last time I checked, they were less than $200, but fabbing linkage, and connection to your compressor would be extra...(of course this would be super cool too...)

Oooohhh, never thought of that. . . that would be super cool. Locating and mounting would be a bitch though. . .