Master Power MPAC521 manual and testing?

Published Categorized as Alltrade 8 Comments on Master Power MPAC521 manual and testing?

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by william clough
(spray, oregon)

I’m looking for service manual and/or user manual for Master Power air compressor by cooper tools model #mpac521 twin stacked tanks w/150psi max.

Master Power air compressor MAC 521
Master Power air compressor MAC 521

Trouble shooting and testing of condenser and check valve.


Is this it?
by: Doug in

Please copy and past the URL in to your browser to see if it still works, and, is this close to yours?


by: Anonymous

I’m looking for the parts listing/manual for mpac521 t00.


mpac 521 compressor
by: Bill

There is a URL to a compressor by Alltrade Tools in this thread.

If that URL isn’t the manual you want, the only other Alltrade compressor I can find is here:

Maybe visit this page, get the contact info for Alltrade and give them a shout?

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HEY GUYS.. the Alltrade 64376 is similar but parts do not interchange as different Manufactures….

I have one of these I got from job. It had the capacitors removed and circuit breaker disconnected. I would appreciate it if someone would be kind enough to share wiring schematic

Last edited 2 years ago by Juan

There is typically no wiring diagram for these small compressors. The *best* you usually get is the values of the caps.
Try the links above. There may be a parts list you can use. If you can get the right caps, we can probably help figure out how they connect.

Good luck.

Did you find parts for this compressor? I’m looking for a replacement pump. Everything’s else is fine but the pump is not putting out air. Costco purchase about 15 years ago. If you still need the manual I can send pdf. Not much in it though, no parts list and Cooper Tools is just a wholesaler of hand tools (nice tools though) in Apex, NC. I can get any contact information for the operation. As you probably know, Alltrade has nothing to do with these particular Chinese tools.

Sure. The manual would be great. Pls just upload it in a comment to this thread. You can attach it to the comment by clicking the “paper clip” icon. Cheers.

Anyway you can send me the manual for the MPAC512 Air Compressor as well?


Looking for a manifold for a power master mpac521

Air compressor