Navman fuel flow reading when engine is stopped

[rustymarlin]

I have the navman 5500 gps and have installed the fuel flow transducer. It works spot on when travelling with the motor running flow looks like i would expect but when I pull up and shut the motor down the fuel flow continues to read and its saying im using 20 litres an hour. As soon as i start the motor back up down it goes to the right reading can anyone give me an idea of what is going on with this unit have i missed something .

Rusty

[Steven78]

How is the Transducer mount? I is mounted virtical? It could be a problem with the fuel primer bulb leting the fuel flow backwards to the tank.

[rustymarlin]

the fuel transducer is mounted vertically and the primer bulb is new and is always hard when you squeeze it .

[garman1]

Have a look at your navman manual and find the section about "auto power", there is a different wiring setup for navman unit with a fuel transducer.

In the power/data cable there are 8 wires, black neg, red main power and the yellow wire is connected into the ignition circuit. I also think in the main menu you have to select "auto power" as well.

I have a navman 8084 and do not have the wiring setup properly and the unit will not show engine hours, because the yellow wire is not hooked up to the ignition circuit yet.

I think that this may also be your problem, have a look at the wiring harness.

I would be very interested to find out if this cures your problems ??

[John Buoy]

I have the navman 5500 gps and have installed the fuel flow transducer. It works spot on when travelling with the motor running flow looks like i would expect but when I pull up and shut the motor down the fuel flow continues to read and its saying im using 20 litres an hour. As soon as i start the motor back up down it goes to the right reading can anyone give me an idea of what is going on with this unit have i missed something .

Rusty

It's quite possible that a whole heap of fuel is rushing back into your tank
when you switch your engine off.
Rusty what engine are you running and does your tank have a return fuel flow?
If not you might need to control the flow with a non return valve in your line!
The wiring part of it will only dictate how your unit switches on or off!
If you want your unit to switch on/off with your ignition then hook up the Yellow
to your ignition +
Regards Frank

[John Buoy]

Have a look at your navman manual and find the section about "auto power", there is a different wiring setup for navman unit with a fuel transducer.

In the power/data cable there are 8 wires, black neg, red main power and the yellow wire is connected into the ignition circuit. I also think in the main menu you have to select "auto power" as well.

I have a navman 8084 and do not have the wiring setup properly and the unit will not show engine hours, because the yellow wire is not hooked up to the ignition circuit yet.

I think that this may also be your problem, have a look at the wiring harness.

I would be very interested to find out if this cures your problems ??

The wirng set up only dictates how you want your unit to switch on or off.
With a fuel flow transducer it is wise to set up the unit to power on or off with ignition switch.
This is achieved by connecting the yellow NMEA connector to your ignition +

Regards Frank