1998 Chevy S-10 warm air

I recently bought a use s10 and tried to use the ac and it did not work, only blew warm air. I check the static pressure and it did have r134a in it and the compressor does ingage, but both high and low pressure remain the same and no movement of the pressure gauges where noticed. I vacuumed/recovered the ac system pulled the the expantion valve out to clean and inspect. Reinstalled the expantion valve and recharge system with 1.75lbs of r134 and compressor still iingauges and still same condition as before, warm air and pressure readings are even and no movement of pressure readings. Is the system clogged some where else or the compressor not pumping?