Question i bought from you mytee 1003 dx. and the cat pump c313a works not so good recently . it takes a few seconds until the pressure goes up again when i am working with my hand wand sprayer . does it has a silling kit pump ? what i have to do to fix it ?

Answer: Please note that 99% of pump issues are operator caused and not a pump issue.
3 items need to be addressed.
1. You need to clean both stainless water filters and re-install. One is located inside the fresh water tank and the other inside the motor box.
2. You must lubricate and or rebuild and lubricate the pressure regulator.
3. You must vacuum prime the pump.

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Under the hood pump water filter
Pumptec Strainer Water Filter for Carpet Cleaning machine and similar B175 1 2 Barbed X 1 2 Barbed 25-186, LSP-1 2B-B-80SS-CB, Water Filters - Low & High Pressure, Filters, Parts & Accessories, by Pumptec, DESC LINE STRAINER, Dual ½ BARB...

rebuild pressure regulator
Pumptec Brass Pressure Regulator Repair Kit for 200 to 500 psi regulators, 250-33A, Repair Parts, Parts & Accessories, by Pumptec, A repair kit for Pumptec brass pressure regulator. The most common repair kit for Mytee, Century 400, Ninja, Speedste...

Vacuum prime pump

Mytee 1003dx

Cat C313a Pump
Cat 1XP150.051 Mytee C313A Masterblend 720450 500psi 1.5Gpm 1 2Hp Ac Motor Water Pump Carpet Cleaning Machines Powrflite CP500AC, 1XP150.051, Cat Pumps, Pumps Water Pumps , Parts & Accessories, by Cat Pumps,  Cat 1XP150.051 Mytee C313A 500psi ...

After you completed steps one through 3 the next step would be to bench test the pump.