Remove the nozzle using the quick connect as explained here and increase the pressure on the machine to 60 psi. On the bottom of the machine, switch the choke valve to 100 percent air by turning the valve parallel with the hose. This puts the maximum amount of air through the system. Next, hold the hose with a strong grip and turn on the machine. Be aware that this can create static shock due to the high pressure. Finally, step on the foot pedal and blow out all abrasive and possible debris, making sure to run the machine until everything is cleaned out of the hoses. This could take anywhere from 30 seconds to two minutes.
Unclogging the nozzle and/or performing a purge on the machine will fix your clogged abrasive problem 95 percent of the time; however, if these two steps don’t solve your issue, you may need to dig deeper. Additional clogs may be in the bottom of the pressure pot, mixing valve, or in the lines. You may need to disassemble the parts and use some compressed air to make sure everything is cleaned out.
-Wes Barton, IKONICS Imaging
