Brass gear pumps are commonly used for pest control applications and weed control spraying. Our favorite brands are Continental Belton & Oberdorfer Pumps. Properly used and maintained, these pumps can provide long-term, effective service. They can be rebuilt to extend pump life.
The photo on the right shows a Continental Belton Gear Pump (brass) that has reached the end of it's life.
You can see the gears are worn down on the ends. If this was the only problem, we could replace the gears to rebuild the pump. The pen is pointing to a portion of the casing that shows uneven wear from the lower gear. This occurred because the bearing that holds the shaft failed.
In our experience, once the bearings in these gear pumps go, it is time for a new pump. When you grasp the pump shaft, if you can shake the shaft then chances are the bearings are shot. It is normally not worth rebuilding the pump. UPDATE: Continental Belton pumps are no longer available. We recommend Orberdorfer Pumps.