What to do when your Snapper gas pressure washer won't mix detergent with spray
Using the wrong spray tip to apply detergent can prevent the detergent from mixing properly with the spray. Use the low-pressure spray tip (usually the black tip) when applying detergent.
A clog in the detergent siphon tube can also inhibit proper detergent mixing. Check the siphon tube for a clog and clean the tube if necessary.
If the siphon tube is clear, then you'll likely need to replace the chemical injection valve on your pressure washer using a chemical injection valve replacement kit.
What causes a Snapper gas pressure washer to spray too hard
A failed unloader valve can cause high pressure at the nozzle. The unloader valve recirculates water to the pump inlet when the pump is running but the spray wand isn't in use. If the unloader valve sticks shut, outlet water pressure builds up until you trigger the spray wand or the pressure relief valve trips to release excess pressure. Replace the unloader valve if excessive pressure builds when the spray wand isn't in use.
Some pressure washers have a pressure regulator that limits the water pressure. A defective pressure regulator can cause high pressure at the nozzle. Replace the pressure regulator if it doesn't regulate outlet water pressure properly.