I am trying to help out a friend in setting up his fuel system for his new N.A. 540. He has a Gen V block with no provisions for mounting a mechanical fuel pump to the block. He will have to rely on his belt driven seawater pump to mount the pump. He has an electric pump which will be hooked up the usual way with the check valve but he wants a back up mechanical as well.
What pump are you guys running that will fit on the seawater pump and have a decent gallons per hour rate?

Hardin Marine makes a kit to update the stock pump.

I've got a Merc fuel pump, brand new in the box, that will fit that application. It was originally for my HP500 but is the same part number as that used all the way up to the supercharged 600hp engine. How's $100 sound?

As I said, it is not for my motor. I finished mine up a while ago, but I will pass on the information.

I use the CV Products' billet pumps with extra valves on my 540 sea pumps.

Ttt

If you have the Merc pump you can bolt that arm onto a Holley Marine Pump. Bolts right up..