Wont hold pressure - Stanley Spray N Go Deluxe Poly 2-gallon Sprayer With Shield 20410m

my pump does not hold pressure when the water is running cuts on at 20psi and the pressure keep droping.

Press the 2nd key, and RELEASE the pressure.
Press the Up Arrow and HOLD pressure.
The screen contrast will increase. Release the pressure of the Arrow key when contrast is to your liking.

40 psi

EXPLAIN WONT HOLD PRESSURE , IF YOU HAVE NO LEAKS AND NO FLUID LOSE.THE MASTER CYLNDER MAY BE BYPASSING INSIDE????

have the fuel pump checked, if its not holding the pressure your gonna get stuck someplace someday,, replace it while its still being nice !!

where does it leak?? and does the pressure rise above 3bar when the heating is on

is your tank filled with water

try force feeding the pump first, this can help to clear any dirt which might be in the valves.
you have 6 valves which are all the same , but 3 are suction and 3 are for pressure.
just take them out and put under a slow dripping tap and fill with water, if the water holds inside the valve will be ok, if it leaks just check for dirt.
hope that helps

hi you say it wont hold pressure aftwer 50 psi /do you mean it wont make more than 50 psi
take air cleaner off get a piece of plastic pipe that will fit in your ear /braided fuel pipe is ok ,run the comp up ,put one end of pipe in inlet manifold /other end in your ear ,if you can hear escaping air valve is shot do the same with outlet valve if air escape is mimimum rings and piston are shot hope this helps silk090

your fuel injection system isn't holding residual pressure.  The valve in the fuel pump that holds the pressure is defective.