windshield washer failure

[RedTriumphTr6@aol.com]

Anyone have suggestions for how to diagnose the cause of my 74's windshield 
washer failure?  I push the washer button and hear the sound of what I think 
is the pump humming, but no fluid comes out of the openings on the 
windscreen.  I have plenty of fluid in the bottle...do you think my jets need 
replacement? How can I tell if they do, and would I also need new wheelbox 
assemblies that the jets are attached to...what do these actually do?         
Bob Pierson