Diaphragm Type Metering Pumps

At Madden we have all kinds of statements that in one way or another refer to great quality. That is the competitive advantage we have chosen to center a profitable business around. Because of this choice we know that great customer service is a critical element when it comes to satisfied customers.

The point of this article is to mention and remind everyone of the services and features that Madden offers to achieve great customer service. We makes statements on our website and our documentation that our products are made to be used 24/7/365 and that they are designed with proven, rugged quality in mind. We’re here to back up those statements and make sure they are a reality when our products are working for your business.

Stocking 99% of Pump Parts

Madden keeps inventory with customer emergencies in mind. If something comes up with the pump, we can have parts boxed up and shipped at a moment’s notice. If 24/7/365 pumping is crucial to your business, we would encourage you to keep a spare diaphragm, valve seats, and gaskets on hand. These are wearable parts that are the only common things needing to be occasionally replaced on our pumps.

Fast Response times to Customer/Rep Questions

Our employees are cross trained in the office. Barring special circumstances (employees on sales calls, vacations, sick, etc.) we can usually respond to any inquiries, questions, or requests for quotes within a couple of minutes. This is a result of great employees who have shown a willingness to learn other’s responsibilities. You will never have to wait for days for us to get back to you with a quote. In the cases that come up where research is needed, you’ll know about it and be continuously updated as we work to find an answer, solution, or final price for whatever the inquiry is.

Inspect and Repair Services

At Madden we encourage customers to give us a call or email if you ever have problems with a product. We’ll do our best to trouble shoot the issue with you. But for those times where it just cannot be fixed, we will inspect and service your Madden product. Ship the item(s) to us and we’ll look it over and let you know what needs to be replaced and all of your options for doing so.

Trouble Shooting Chart for Madden Metering Pumps

Problem Cause Solution
1. Uncontrollable output, pumping 5.2 GPH with a 4 GPH pump Supply tank is higher than pump, pump higher than discharge to open tank, allowing liquid to syphon through the pump Install a back pressure valve in the discharge line, or change the suction and discharge head conditions
2. New pump leaking liquid after a few weeks in service Loose bolts caused by creeping rubber diaphragm and/or plastic parts creeping under pressure Snug up solution head and valve cap bolts frequently during the first few weeks of operation
3. No output control Broken or damaged MP048 flexible stroke adjustment shaft Replace broken part, reset the adjustment knob, prevent damage due to turning the knob when pump is not in operation
4. Oil leaking out of pump at stroke adjustment knob Worn out diaphragm is leaking allowing pumpage to enter the pump body displacing the gear box lubricant Replace the diaphragm. Put diaphragm inspection on PM activity list
5. New JN Series pump won’t suck liquid into pump No foot valve to keep liquid in the suction tube, suction tube too large for the pump Install foot valve on new ¼” suction tubing, replacing ½” tubing
6. Can’t get pump with spring loaded valves to operate Pump needs to be primed, pumps with spring loaded valves often are not self-priming Prime the pump by putting pressure on the suction piping, or by priming from the discharge valve
7. No internal pressure relief valve in the pump Not part of the design of the mechanical type diaphragm Install a pressure relief valve in the discharge piping
8. Cannot pump rated volume even though discharge pressure is only 50 psi Liquid has a viscosity of 2,000 centipoise Consider another type of pump, Madden pumps are good for liquids up to the ball park of 500 centipoise
9. PVC pump leaking Discharge pressure is 250 psi which has caused cracks to develop in PVC parts Switch to metal wetted end when discharge pressure exceeds 150 psi


And as always, if you need anything, please feel free to call us at (574) 295-4292.