[cmccuist]

Those oil-less compressors will fail after awhile. You can buy the whole piston/sleeve assembly for about $40. That should get you back up and running again.

I bought a 5 HP Craftsman compressor at a yard sale the other day for $20. It was the vertical tank, 20 gallon. The owner said it stopped building pressure. I broke it down, bought the piston/sleeve kt - it even has the o-rings and got it running again pretty quickly.

You just need to take off the cover, unbolt the valve/reed assembly on the top and see what parts need to be replaced. You can type in the model number on the Sears web site and pick them up at the parts counter.