Dultmeier Sales will be closed Thursday, November 22nd and Friday, November 23rd in observance of Thanksgiving

Dultmeier Sales will be closed Tuesday, December 24th at 12pm and all day Wednesday, December 25th.
Normal operations will resume Thursday, December 26th. We wish you and your family a very Merry Christmas!

Dultmeier Sales will be closed Wednesday, January 1st in observance of
New Year's Day

Dultmeier Sales will be closed Thursday, July 4th and Friday, July 5th in observance of Independence Day.
Normal operations will resume Monday, July 8th. We wish you a happy 4th of July!!

We are experiencing some technical difficulties on dultmeier.com and apologize for any inconvenience.
If you are running into issues, please phone your order in to 1-888-677-5054

Customer Pickup Orders: to help reduce exposure for our customers and our employees, if you are placing an order for in-store pickup please call in your order ahead of time or place your order online and pre-pay with a credit card. Be sure to let us know when you plan to arrive. We will have your merchandise ready for you and will greet you outside our facility. Thank you for your help!

How to Service Valves on Plunger Pumps | Video

In this video, CAT Pumps® demonstrates how to service the valves on a plunger pump. This step-by-step tutorial includes the tools needed to service the valves, disassembly of the valves, inspection, maintenance, and repair of the valves, and reassembly of the valves. The techniques shown in the video apply to the 66DX, 6DX, and 5DX CAT Pumps.

View our other Cat Pumps videos here!


Plunger pumps are a type of positive displacement pump that moves fluid by expanding and contracting a cavity. During the contracting of the cavity via a plunger rod, a discharge valve is forced open, expelling fluid. The rod then begins to move backward, closing the discharge valve and opening an inlet valve, drawing in more liquid.

CAT PUMPS® offers a few different designs of piston and plunger pumps, including a direct flow pump, a "Superflow" pump that includes a flow-through ceramic plunger, and a flushing port pump that includes an inlet and outlet pump to circulate a flushing liquid through the pump, extending pump life when operating with special materials.