Fuel flow gauge transducer install

[R&T Babich]

I'm installing a Faria fuel flow gauge in our 2000 21V. The fuel filter base has a neoprene hose from the tank connected to an input, a braided hose out to the pump and a braided hose in from the pump. I'm wondering if I can take the two braided hoses off the base and connect them to a tee. Then, I could add the fuel flow transducer between the filter base and the tee. Also, plug the old pump return input.
The original pump return line fed into the filter so the fuel would get filtered a second time. Going back thru a tee shouldn't really be any different on pressures in the system. I wouldn't need a second filter in front of the transducer and there isn't a lot of room on the other side of the filter base for the transducer because it would be very close to the drive belt.

[chpthril]

Having a little trouble visualizing how you want to install this (post a pic or diagram if you can), but I would recommend against changing the designed flow of the fuel. This could create not only an unsafe system, but may have an adverse effect on engine performance such as an over-pressure, which will lead to a rich condition, or a low pressure condition that will starve the engine and it will run lean.

I would stick to the recommended install: pre-filter before the transducer, mount transducer vertical and before the pump so you are not splicing into the high pressure side of the fuel system.

Take some pics, and we can certainly find a good place to mount the transducer. Good luck.

[R&T Babich]

Hi, chpthril,
I'll try to get pics or a drawing. The SS braided hoses connected to the fuel filter base are not the larger SS braided hi-press hose that goes from the pump to the fuel rails up the back of the engine. I don't think the return hose is hi-press because the filter couldn't take it. I think the 2 hoses from the filter base are SS braided because they go under the engine to the other side where the cooler/pump is and it would be safer using that type of line. I'll try asking Merc (350 Mag MPI) about that. Talking about safe, both the battery leads were run down into the bottom of the bilge next to the fuel supply line. Any water in the bilge and the leads are under water. Watch those filters, too. They're in a plastic case out of sight. I had one get a pin hole leak in the side of the shell after 1 season on our last boat.

[spharis]

The recommended install is to cut the main supply line at a vertical location, install a 3/8" metal can style filter (available at autozone), short hose, then the transducer. Regardless, everything is on the low pressure side of the fuel system. This is how mine is setup, and is at least 18 inches before the main filter assly.. I was running a glass filter until I could get by the parts store for a metal one, and after the recommendation of members here.