Advice needed - Navman fuel flow

[mellon]

Can anyone please provide some information as i am thinking about purchasing a NAVMAN 2100 fuel flow meter and installing it to my boat. I have a 75 Hp Mariner 4 stroke on a 5 mt Quintrex.

My only query at this stage is that it is recommended that the Navman fuel flowmeters are installed into motors 90 hp and above as the rate of fuel needs to be over 5 l/ hr or there abouts.

has anyone installed one of these to a motor with less HP than they recommended...

anyway advice would be appreciated.

Cheers

Neil
Darwin NT

[cajunnsw]

It worked great on my 3cyl 70hp Johnno, but when I updated to a Yammie 60HP 4st, it doesn't work any more ...

[Far side]

check out the navman web site I believe they have a fuel flow meter for smaller engines

[Kiktz]

Cajunn,

I think you have just answered my question for me.

We have one on our boat, with the 100ho 2str it worked fine.
Now with the 175 4str, it doesn't work any more. May be it is the flow rate of the fuel that is causing the problem.

Aj

[mark221263]

Fuel flow rates below 2.5 lt/hr will start to give inaccurate readings. Northstar who took over navman claim accurate readings bewteen 2.5 and 130 lt/hr for the f210 unit which is a rebadges Navman fuel 2100.

When at cruise though the meter should still work fine.

Make sure you dont have a fuel return line as the 2100 won't account for the fuel being returned to your tank. Also a some of the 4stk engines dont use a constant feed of fuel as they can pump up the fuel rail to a target pressure and then stop start the fuel pump the flow to the outboard is not constant. You can adjust for this by adjusting the average value the meter usess, mine is set at 10 seconds but you may need twice that compared to my 2 stroke.

I read down to about 5 lt/hr at idle but have syphoned through my fuel line to record values as low as 1 lt/hr and my meter still appears accurate.

As far as the units that stopped working I'd be looking to see if some contamination entered the transducer when the engine swap occured as if it was a low flow problem it should still read above idle.

Cheers Mark

[Kiktz]

Cheers Mark,

That kinda makes sence to me. We have tried to adjust the values
in the fuel matre. But as we bought the boat 2nd hand we dont have any info
on how to use it. Do you know where I can get my hands on the steeing information that I will need to change

Thanks Aj

[mark221263]

you can down load the info manual from the navman site.

go to

http://www.navman.com/upload/Marine/...7A_eng_web.pdf

the time used for calulating the fuel flow is the second option that comes up after calibration and show on the screen as AUG whichis for average. Preset value is 10 seconds and this can be changed between 1 and 99. This is an new revision tot he units software that does not show in the download manual.

But the instructions for this part on a seperate sheet with my unit stated,

New feature Flow filter (Software upgrade V 3.1.) addendum
The Flow Filter sets the period over which the fuel flow is averaged. The period can be set from 1 to 99 seconds.

Normal engines do not draw fuel from the tank at a constant rate. They draw fuel at a higher rate for a short time until the carburettor bowl or injection reservoir is full, then draw no fuel for a few seconds. If the true flow rate was displayed, it would be too erratic to read.

Usually a value of 10 to 15 seconds will give satisfactory results for two stroke naturally carburetted engines.

Four stroke and engines that use electronic fuel injection may require longer periods. If the readings displayed seem erratic you can increase the period. The factory default is 10 seconds.

A larger period means that the fuel flow display will have a slower response time and more stable readings are displayed, while a shorter period means that the fuel flow display will have a quick response time and more erratic readings displayed.

The flow filter period only affects the fuel flow display. It does not affect the accuracy of other measurements.

(E.g. Fuel Used or Fuel Remaining).
How to Enter the Flow Filter menu:
1. Hold down the Flow key when turning unit on to enter the Fuel Calibration menu.
2. Press and hold both the Flow and Total keys simultaneously for 2 seconds to enter the Fuel Filter mode.
3. Fuel flow average period menu AVG is displayed briefly and the value in seconds is displayed.
4. Use the (Flow) and (Total) keys to select a new value between 1 and 99 seconds.
5. Press and Hold both keys for one second to save the new averaging period and return to normal operation.


Cheers mark