flow scan

We bought an older boat that has a single 5.9 Cummins 210 HP. This boat came with a flow scan, which appears to not be operable. My question is: Is a flow scan worth the trouble and money to repair? Never had one before and do not know how it would help me that much.

Had one on a gas boat and extremely accurate, and can be calibrated on rear with little switches. On a diesel engine there are two sending units, one is the supply and one in the return lines. Either of those may not be working or it may be the gauge itself. Possible you may find a troubleshooting guide for FloScan on line

They are an easy company to work with - give them a call Monday.

Floscan Instrument Co. Inc.

I have that exact same engine and a FloScan as well.
My sender failed and I called FloScan to order another.
They told me to try connecting a wire from the case of the sender to ground.
It worked! Give them a call and see if there is a cheap fix. If not, buy a new one. It's worth it.

Gotta love those Floscans. Once properly calibrated they are much more accurate than fuel gauges, give you best MPG or GPH in real time etc etc. Not a necessity but are sure nice to have.

Depends, if you run your boat at 7 knots it will not be very useful. If you run at 12 knots you may find it more helpful. I had one on a boat with a 454 gas engine and it was very helpful.

I have one pulled off the old engines during refit. Oddly, although used on a diesel it had only one sender. There was no return fuel line sender. The mechanics removed it, and it must have been installed after the fuel return. I think it might have been a gas (petrol) unit. But it worked really well the way it was installed. I really ought to sell it, if anyone in Australia is interested then PM me.

Insequent said:

I have one pulled off the old engines during refit. Oddly, although used on a diesel it had only one sender. There was no return fuel line sender. The mechanics removed it, and it must have been installed after the fuel return. I think it might have been a gas (petrol) unit. But it worked really well the way it was installed. I really ought to sell it, if anyone in Australia is interested then PM me.

Click to expand...

I'd love to know how that could work, those are pricy units with two senders.

boatpoker said:

I'd love to know how that could work, those are pricy units with two senders.

Click to expand...

Yes, we were surprised. But the mechanic was looking for a second sender during removal and did not find it and I searched after the engine was out as well. I agree, it doesn't seem right.

If my boat had one I would certainly look into repairing it. I think knowing actual fuel consumption would be much more useful than two needles bouncing around on the dash.


I don't use enough fuel to make a new installation cost effective or I would do it.

The Flow Scan monitoring system is like a two pronged fork. The good side of it is that you know exactly how much fuel you're burning. The bad side is that you know exactly how much fuel you're burning.

Although the FloScan can be very accurate, calibrating it is not as simple as is implied here. I've had two FloScans in the past & getting them to agree with what I took on at the pump, vs, what they said I burned, was no easy matter. I never did get them to agree with what I had actually burned. I have no ax to grind with the FloScan people.....I would prefer a fuel monitor that is much easier to calibrate.

I don't recall having to calibrate mine, but I installed it more than twenty years ago. I might just not remember doing it. Mine was very accurate. If it said I'd burned 50 gallons I'd put back within a gallon on either side of fifty. It finally gave up a couple of years ago and a new one is on the list.

Codger2: "Although the FloScan can be very accurate, calibrating it is not as simple as is implied here. I've had two FloScans in the past & getting them to agree with what I took on at the pump, vs, what they said I burned, was no easy matter. I never did get them to agree with what I had actually burned. I have no ax to grind with the FloScan people.....I would prefer a fuel monitor that is much easier to calibrate."

I also struggled with the calibration issue - they recommend 3 tank refills in order to make the system accurate. Didn't install for 4 years after purchase, so my fault to start with.

After install, couldn't get the system to work. Had to buy a new meter. After 2 refills, the other meter quit. After re-install, got through 3 refills and found the calibration settings were not sufficient (they only adjust to 8%?). Took the meters/gauge into FloScan, ended up buying a new meter. After 3 more refills, was able to get the system calibrated and it was very accurate for about 18 months.

Then it stopped, and was advised that a meter needed to be replaced, and that it would not work with the other meter, so would need two new meters.

So - After 10 years, $1300 and a large number of hours, I gave up on it. However, I was able to record very accurate consumption rates at varying speeds that serve me well today. 6BT5.9 210hp.

Awesome support - I had mine rebuilt a few years ago, very convenient behind U Village in Seattle.


Keith

I have two fitted to Liberty, that were on it when we purchased her. I am like Codger2 , they just don't make sense, and fuel usage is well and truely overstated. May be they require re calibration?. I have done enough miles now , and with that some long legs, so have a close idea from our logs exactly what we are burning on a selected RPM and speed over ground, so probably won't worry about replacing them. I have heard mixed reports regarding the flo scan units, much the same as this thread.
Any way that's my experience for what it is worth.

Chris D Liberty 2015

After the initial setup , the calibration is simple.

The tank is refilled and the gauge gallon readout is matched to the actual fuel burn

A little rotary switch on the back of the gauge usually will get you Almost there.

After another tank fill 80 to 200+ gal , not 10 gal the process is done again.

3rd time the gauge will frequently be so close you wont care.

If you have a mechanical sender the included tach is very accurate.

The flow scan is very useful if you care about fuel use , as you can ,with a GPS make a simple chart of MPH vs GPH .

Speed cost money , even at the trawler crawl .

The newest units have a GPS hookup and will readout in NMPG as you wish.

When I installed one the problem was air bubbles getting in will mess up the readings was hard to track down wear the air was getting in

Pure pleasure said:

When I installed one the problem was air bubbles getting in will mess up the readings was hard to track down wear the air was getting in

Click to expand...

Air bubbles mess up the reading? Enough air and you fill a filter and kill the engine. Getting rid of air is critical.


Keith

Which reminds me, my calibrated sight tubes never need recalibration. Even worked well on a 30' SeaRay.

Ya got it to work will use sight glass from now on will not do that again

I have installed them on two outboard fishing boats and my previous trawler, a Camano with a 210 HP Volvo diesel. I didn't find them difficult to install especially on the gas units. Calibrated per manual and after a few fillups found the "totalizer", fuel consumed, accurate.
This Monk 36 has sight tubes on the tanks so it is easy to keep an eye on fuel available.
I haven't installed one here yet, maybe a future project.

I've set up a few boats with flowscans. They work well on engines that burn LOTS of fuel. On a trawler with a B210 running hull speed, you are down around 1-3gph and that low on the scale it is a pretty coarse reading. Also with two flow meters, you are calculating gph by subtracting two numbers close to each other, and each with an accuracy. Total "inaccuracy" then can be quite large.

My preference is dipsticks or sight level gauges. In the number of tanks needed to cal the flowscans, you can determine burn rate using sticks or sight level.

Also, the cal on the flowscan can be made accurate at one power setting, that does not mean it will be accurate at some other power setting. This is a concern down at the low end of gph flow, not so much on the mid to upper end of the instruments range.

Sticks and sight tubes rule!!

A stick is what I had in mind instead of using the FloScan. We will seldom run over 7 or 8 knots.

But a fuel flow meter tied to your MFD can calculate your most efficient fuel burn RPM. A dipstick cannot do that.

Wes, IMHO on my boat WLL rules. The desire for greater efficiency than an approximate 1.1 factor in terms of NMPG is well down my list of important issues. Just me I'm sure.

WesK said:

But a fuel flow meter tied to your MFD can calculate your most efficient fuel burn RPM. A dipstick cannot do that.

Click to expand...

Sure it can. I take a leg of a trip at 1800rp/17kts, dip tank and log hrs and nm. End of run do a dip and a calc. Repeated for 1900/18kts and 2100/21kts. Also did for 950/7.5 and 1050/8.0.

Each leg was at least a few hours to get the granularity out of the numbers. I now know burn rate for each power setting.

It took about as many tank fills as a flowscan cal. And I check it periodically. Numbers are very repeatable.

950 1.9gph
1050 2.3
1800 8
1900 9
2100 12

Those are the only speeds where the boat feels happy, so I'm not too interested in other power settings. 2000 gives me an annoying prop tip vibe, so I avoid that. Got all the numbers I need with a wooden stick. And a gps, clock and calculator!!

Ski in NC said:

Sure it can. I take a leg of a trip at 1800rp/17kts, dip tank and log hrs and nm. End of run do a dip and a calc. Repeated for 1900/18kts and 2100/21kts. Also did for 950/7.5 and 1050/8.0.

Each leg was at least a few hours to get the granularity out of the numbers. I now know burn rate for each power setting.

It took about as many tank fills as a flowscan cal. And I check it periodically. Numbers are very repeatable.

950 1.9gph
1050 2.3
1800 8
1900 9
2100 12

Those are the only speeds where the boat feels happy, so I'm not too interested in other power settings. 2000 gives me an annoying prop tip vibe, so I avoid that. Got all the numbers I need with a wooden stick. And a gps, clock and calculator!!

Click to expand...

Damn Ski, 21kts@12gph is pretty damn awesome!!!...any of those numbers are pretty badass. I am pretty much a gallon a mile up on plane.

I do need to do something though. When my 108 gallon tanks read 1/8 of a tank, they have every bit of 1/4+ in them. I don't have the cojones to run them down to "E" so I switch over too early. Having 3 identical tanks I end up with about 80 gallons of fuel when I "think" it is time to get fuel....ie all tanks reading 1/8 of a tank. I would like to burn those tanks down a little lower with peace of mind.

Fuel transfer pump, make your switch overs then pump two previous tanks
empty into the last tank.
I had a single tank on my tractor-truck, changed the sending unit three times
in the first year. They all failed. Ran it on the trip meter (same daily run with
minor variations). Won't trust them in boats or major trucks.

Ted

Never bothered to calibrate my FloScan. Based on engine manufacturer's theoretical information and observed usage, I merely multiply the reading by 70 percent.