A cement fountain is made to last for decades with proper maintenance, but even the best maintained fountains can develop issues that require repair. There are two main areas of repair with a cement fountain: the pump and the stone. Most issues short of replacement of the fountain you can fix yourself, and due to the robust nature of the materials used to create the fountain, these fixes are generally inexpensive and quick, accomplished with supplies found at any home improvement store.
Turn off the fountain and drain the water basin completely. Clean the fountain, including the water feed hose and the drainage system. Clean fountain pumps using a mixture of two cups vinegar with a gallon of water. Remove dirt and debris from the pump, then soak the pump in the vinegar mixture, running the pump for 30 minutes.
Examine the fountain for any breaks, cracks or holes.
Repair broken stone using a quick patch epoxy. Quick patch epoxy is a two-part adhesive that when mixed forms a quick-binding material that immediately binds the stone pieces and cures in 24 hours. Mix the epoxy and spread a layer on both pieces of the broken stone using a putty knife. Firmly place the stone pieces together and hold for at least two minutes to allow the pieces to set. Wipe away excess epoxy on the surface of the fountain using a cloth. Allow the epoxy to cure.
Repair small cracks and chips in the cement by filling the areas with a quick-setting anchoring cement. Mix the cement to a pastelike consistency and completely fill the cracks and chips with the cement using a small garden trowel. Allow the cement to set for 15 minutes.
Repair larger holes or restore a pitted surface using the quick set cement. Mix the cement and fill the holes with it, shaping the top of the patch. To smooth the patch's surface, mix a second, smaller batch of cement to the consistency of paint, and apply a layer of the thinned mix to the surface of the patch using a paint brush.
Seal the repaired fountain by spraying the fountain's surface with a concrete sealer. If the fountain was painted previously, remove loose paint and scrub the old paint surface with a wire brush to texture the paint. Repaint the fountain and allow to dry completely.
Reinsert the pump into the fountain and attach the hoses. Turn on the fountain for use.