15974 Meyer 1 Piece Cross Over Valve Power Angling Block Plow Pump Diamond Crossover

As of 10-22 Meyer has Discontinued these and you will have to look for an aftermarket solution once sold out. 

A New Genuine Meyer 15974 One Piece Crossover Relief Valve. Most of the earlier pumps used the multi piece 15606 crossover, but this one is a preset and a direct replacement. This can be used on many of the Meyer plow pumps, including: E-45, E-47, E-48, E-50, E-57, E-60, E-58, E68, E88 and E61. It comes with the seals. Below are some rebuild manuals to show you how to install. This valve is designed to let fluid bypass if you hit something. When they go bad, the plow will often drift without much weight against it.

E-47, E-46 Complete Service Rebuild Manual.

E-47, E-46 Parts Break Down.

E-47H, E-46H Parts Break Down.