SUPER SUN AP-25
Plastic Knapsack Sprayer
(Piston Pump Model)

Maintenance & Repair : When severely worn, the piston, cylinder and #44 piston collar in the model AP-25 sprayer will lose pumping efficiency and can leak liquid. Repair immediately. Do not use when leaking. --Avoid excessive wear by : 1) Regular lubrication of #44 piston collar, cylinder, and piston with non-water grease* 2) Petroleum Jelly works well... 3) Prompt and thorough cleaning and flushing of sprayer with liquid detergent soap and water work well. Pump Disassembly and Service: Remove the nut and bolt from the #50 blue protective cup (not shown in figure one). Next, remove the two #2 stud bolts from the #42 chrome plated lever (A). By holding on to #42 lever, pull the piston out of the cylinder (B). Apply a coat of non-water soluble grease around the top edge of the #44 piston collar and the inside of the cylinder (see figure two). Re-install in reverse order, being careful not to damage the #44 piston collar. When? Every 30 days for commercial users or end of season for infrequent users. Pump Worn or Leaking : If liquid seeps through the small hole in the #50 blue protective cup over the piston pump, the #44 collar must be replaced. Look for wear! Disassemble as above in Figure 1 and push the #44 piston collar off the #43 piston. Then push on a new #44 collar onto the #43 piston. Lubricate and reinstall (see figure II). Examine the inside of the cylinder for scratches (scoring). If the cylinder is scratched, it also must be replaced as the scratches will cause rapid wear of the #44 collar. Also, check the outside of the piston for scratches. Scratches are caused by abrasive material, contaminated spray mix or lack of lubrication on the #44 piston collar. SOLUTION! INSTALL #100 PISTON PUMP KIT: If the #40 cylinder and #43 piston look OK, we recommend replacing all old worn parts on the #40 cylinder assembly (including the #44 piston collar on the #43 piston as described above) with the #100 piston pump kit.  Use channel locks, etc., to unscrew the #40 cylinder ass'y from the #39 pressure dome tank.  Then remove and replace the #12 and #13 o-rings and the (2) #20 check valve plates (one inside and one on top of the #40 cylinder).  The larger #11 o-ring goes on the bottom of the #39 dome tank.  Loosen the #16 clamp and drop (tap down from inside main tank) the #39 dome tank for installation of the #11 o-ring.  Re-install pump ass'y and you are ready to spray again. REPAIRS WILL SELDOM BE NECESSARY IF YOU ALWAYS FLUSH OUT THE SPRAYER'S TANK WITH SOAP AND FRESH WATER IMMEDIATELY WHEN THROUGH SPRAYING, AND CONTINUE TO LUBRICATE THE #44 PISTON COLLAR ACCORDING TO HOW MUCH YOUR SPRAYER IS USED!!! This advice should be followed with any other brand of sprayers as well as the AP-25. | HOME |