Pat Norman
New member
Well recently when I installed a new K7 unloader, I also installed a permanent pressure gauge between the pump and unloader. In the past I've always used a temporary quick connect gauge at the reel and at the end of the hose to occasionally check my pressure. So now I am really starting to understand the back pressure caused by 200 feet of 3/8 hose. When using a #60 orifice with my 8gpm x 3500 psi machine creates 2900 psi at the pump and 1000 psi at the gun (when using a 2.1 injector). Without the injector the #60 creates about 1800 at the pump and 1000 at the gun. With an #8.5 orifice and no injector I am getting 3500 psi at the pump and about 3200 at the gun.
So here is my question, if I change to say 170 feet of 1/2" hose and put a 30 foot "tail" of 3/8" hose so that the end won't be so darn heavy will I gain any performance in psi, gpm, better soap draw (I draw pretty darn good right now using the 2.1 injector), less lag-time in the K7 unloader giving me pressure ? Seems like the combo of 1/2" with a 3/8 tail might be best of both worlds.
So here is my question, if I change to say 170 feet of 1/2" hose and put a 30 foot "tail" of 3/8" hose so that the end won't be so darn heavy will I gain any performance in psi, gpm, better soap draw (I draw pretty darn good right now using the 2.1 injector), less lag-time in the K7 unloader giving me pressure ? Seems like the combo of 1/2" with a 3/8 tail might be best of both worlds.