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Instructions for Replacing the Diaphragm Pump

Applicable to the following units:

SP1
SP1E
SP2
SP3
EstateKeeper
Farm & Home 477 Diaphragm
SP1/C

Step-by-step how to:

Unscrew both nuts which hold the diaphragm crank to the pump handle. Remove both nuts and pressure washers. Pull crank away from the two screws. It is not necessary to remove the aluminum crank from the diaphragm.

Remove the clip that holds the pump handle in the spray pack.

Slide the pump handle slowly to the left, then slip out the screws from the pump handle completely. Slide the pump handle completely from the spray pack. Be sure not to lose the nylon washers.

Remove the hose from the sprayer by removing the 90° fitting and hose clamp.

The diaphragm is now exposed and can be removed.

Place a large rubber band over the circular metal ring that holds the diaphragm together or use a pair of gloves to grip the pump module. Turn the complete diaphragm counter-clockwise until it is completely unscrewed from the spray pack. Discard the old diaphragm.

Once the diaphragm has been removed, you will notice a small mark or protrusion, both on the diaphragm and on the spray pack. When the new diaphragm is installed, these marks must align for proper functioning.

Oil the O-rings to prevent damage and to make threading easier. Place the diaphragm in the proper position and turn clockwise. Continue to turn until the large O-ring on the diaphragm is no longer visible. Make sure that the markings on the diaphragm and the spray pack are aligned.

Replace the pump handle into the spray pack. Make sure the nylon washers are in place. Slide the handle in slowly and immediately replace the screws to the screw holes, one at a time.

Push the pump handle all the way into the sprayer and replace the pin.

Connect the hose by inserting the 90° fitting into its original position and tighten the hose clamp.

Replace the screws through the holes on the aluminum crank. Replace pressure washer and nut. Tighten firmly.

Your sprayer is now ready to use.