loop your return line back into the suction just prior to the lift pump.

You must also valve it so you can manually return fuel to the tank so you can purge any air in the system when changing fuel filters.

I did this with tees and ball valves.

This setup will supply plenty fuel and your filters last longer because you only filter once as opposed to the factory return setup (pumping more than double or triple the rate of fuel burned and returning it to the tank to be filtered again.

trust me this works good, i have been using this setup for many miles.

Filters before the selector valve for fast changover times.

Be sure of your connections for air leaks

Steve

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85 300d in progress