Help with anti syphon Perkins 4.108

[jimjimmyjimjim]

I'm replacing the exhaust system on my rebuilt Perkins and I need to install an anti-syphon loop. The loop is usually placed inline between the exit of the manifold and the water inlet on the exhaust pipe. I don't have room there so I'm thinking of putting the loop between the water pump">raw water pump and the INlet of the heat exchanger/manifold (see photo). Is this a bad idea and why? Thanks, JH