Grumpy gits and useful tips: KARCHER LOST PRESSURE?
SIMPSON Complete Bypass Manifold Replacement Kit for AAA 540001 and 540005 Axial Cam Pressure Washer Pump, Black in the Pressure Washer Parts department at Lowes.com
Bypass Valve, K4-k5 Karcher 9.002-164.0 Spare Part For Mini Washers, Accessories For Mini Washers, Accessories And Spare Parts - Pressure Washer Parts & Accessories - AliExpress
Karcher K5 Control Head
Karcher K5 Pressure Washer Control Head 9.001-800.0 - Genuine Karcher Part | eBay