Outdoor Power Equipment and Small Engines - pressure washer need an O ring??

I have the (borrowed) Honda GC160 pressure washer , and all hooked up and gas up and started up.., it is fine until I start the wand and the tip , which d\fits nicely into an opening that pulls down with a ring of 8 ball bearings inside the tip hold any one of four fittings I have here that will give a variety of different sprays., Trouble is all four that fit nicely are extreamly fault in that any one of the four tips leak so bad that the pressure is cut in half due to the leaky fitting.
Are they to have a O ring of rubber in the center of these fittings.? My Rona man says no they don't need them or use them.. but why the leaky head???

The only other option I have to do now is to tape it with heavy rubberized electrician tape and that will hold back some or most of the leak..

It almost sounds like the wrong fittings... If it's borrowed from Rona,, take it back to them & get another.. If the fittings are a Hanson type Quick connect,, Yes there is "O" rings in them... Roger

turns out- the fitting ( brass) with ball beraings inside. is where the O ring goes.., There was none inside,.. I was initally thought the O ring went on the actual spray fitting itself.. (the four quick connect fittings that have difefrnat angles of spray )..