Flow sensor
 

Got a couple of the old Zemco DCS 310 Car Fuel computers, only problem is the old fuel flow sensors, especially late model high pressure fuel systems.

So looking for fuel flow sensors for high pressure systems.

Rich

Here is a link to a picture of one:

https://www.facebook.com/photo?fbid=...30978023627450

https://www.facebook.com/photo?fbid=...30978023627450

Hey there mate,

Can you elaborate on anything you're looking for? Maybe what model car or what fuel measuring you're trying to achieve?

Is this for a diesel or petrol application?

Cheers

glen

Back in the 70s or 80s Emeco or ENCO made a device kind of like the MPGunio called a Add on “Driving Control System” travel mileage computer.

It worked by mounting two small magnets to your drive shaft, and mounting a small coil on an arm next to the shaft to produce an early version of VSS.

Then you placed in your fuel line near the carb the flow sensor.

Like the MPGunio once calibrated it then gave MPG, Miles left in tank, miles per hour, avg.MPG, MPG on Trip and perhaps a thing of more.

One great thing is as it makes its own signals it is unaffected by anything done to the cars computer and to the injectors. And there is a couple of features that the MPGunio does not do.

The main problem is the flow sensor was made to handle carb and early fuel injection pressures, which in a carb is under 5 PSI and in say TBI systems are under 20PSI.

My Fords with their Port injection run as high as 30/60PSI and higher.

So I fear fuel leaks from these old fuel flow sensors, and it has been reported the BB inside were out so I cannot expect a long life as well.

So thought I would once again look for better newer low cost flow sensors.

My cars are gasoline burning.

Here is a link to a picture of one:

https://www.facebook.com/photo?fbid=...30978023627450

https://www.facebook.com/photo?fbid=...30978023627450

Ah! as I suspected

Well sir, unfortunately unless your fuel injection system is 'returnless' a flow sensor will just return the entire volume of fuel the fuel pump flows through the fuel rail past the injectors and back to the tank.

What features does your other system do that the MPGuino doesn't? I have the ability to add almost anything to the MPGuino Colour to do with fuel usage, milage or trip information.

“Well sir, unfortunately unless your fuel injection system is 'returnless' a flow sensor will just return the entire volume of fuel the fuel pump flows through the fuel rail past the injectors and back to the tank.

First my I figured out how to add aftermarket fuel pressure regulator with a fuel return right next to my TBI system so from it to the injectors is a one way trip. Problem solved. Plus I can then manually change pressures as well.

My o2 Ford Explorer and my 03 Crown Vic are already “Returnless”


What features does your other system do that the MPGuino doesn't? I have the ability to add almost anything to the MPGuino Colour to do with fuel usage, milage or trip information.”

OK I do want a flow sensor so that I can do things to the injector’s pulses and not throw the MPGunio off.

And I want to be able to do things to the PCM and again not throw MPGunio an ScanguageII off, I learned early mess with the PCM and you can get false readings, like 45MPG..when it is only doing 27MPG.

As for other features:

Fuel in tank, by telling the computer the size of the tank and that you just filled up it can tell how many gallons are left at any point.

Told how far you going it can tell you how much fuel will be need to get there and farthere is to get there.
Even est time to get there.
Fuel left in tank and how many miles that will take you on your current MPG.

Granted not really needed, just I really want the real time fuel flow sensor.

One other good feature is you can really calibrate this, Miles Per Hour is done by starting as zero and driving 10 + miles and then correcting its read out, the longer reading will give a more accurate MILES driven and from that MPH.

The MPG is calibrated by the same kind of system for the first 5 to 10 tanks of gas you keep correcting its readings for MPG by calalating the MPG and then correcting the computer, it can be come very accurate with that system.

All I know is that accurately measuring small flow volumes can be tricky. I remember a sensor that used a 'vortex street' of pins the fuel flowed through.

So I put a search term into DuckDuckGo and selected a block from the first page.

Stuff that jumped out at me bolded.

These are features in the MPGuino colour version, which are features i use the most. Distance to empty is extremely useful.

I hope you can find a good flow sensor! I didn't even know such systems were accurate enough for this use! I would be interested for a carburetor application.

Cheers

Well as I am working on tight budget, I try to keep my cost as low as possible.

One good part of this old computer is its dead simple programing, drive a set amount of miles and correct the computers counting of its VSS and the miles traveled and thus all readings using miles traveled is set, speed, MPG etc.

Then with a few fill ups and correction of the systems counts of the flow sensor and your miles per gallon is set and all the fuel readings are also set.

For some of my testing where I am fooling the PCM, I found I get false readings from a Scan GaugeII, and if I do my planed messing with the injector cycles I fear that could mess up the MPHunios readings, as it is set to figure things from the injector duty cycles.

With this set up it is totally totally independent of any of the cars systems. I believe I am just about the only person that could need such a system, and even I may not really need it, but will not know until I test my ideas and see.

I am sure the MPGunio can also be programed about the same way.

The only things it needs is the magnets on the drive shaft and a flow sensor made compatible to its system.

And I think the cost will not be too bad.

Rich

Zemco Fuel injection interface
 

Greetings Gentlemen

Are you aware Zemco made a conversion box for Fuel injection usage ?

It is a relatively basic circuit ,it has already been reverse engineered on www.airforums.com ,just search Zemco.

Tp

First thanks, found the threat: https://www.airforums.com/forums/f15...rs-184587.html

BUT you missed my reason for wanting a fuel flow sensor.

Some of my ideas and plans are to interfere with the systems controlling the fuel injectors directly, lower supply voltages, signals changes etc.

Such acts could mess up the readings.

AS I was using a Scan Gauge II. I was tuning the MAF sensors and the scan gauge II showed I was getting 45 MPG and better.

It was false data, I learned it could not report accurate data when the cars PCM was fooled. A 200 mile test drive from fill up to fill up showed that.

This flaw lead me to this site and the MPGunio which as long as I do not mess with the injectors reads accurate MPG.

BUT it too is dependent of the signals from the injectors so I want to by pass that weakness with a system that reads the real fuel flow used to power the engine.

Rich

Yes ,I now see your need ,although finding such a sensor with a reasonable price might be
a challenge ,I had been experimenting with various cheap sensors ,but their limitations pushed me in the direction of ultrasonic time of flight detection ,I gave up on this when my carbureted T100 engine broke & then went EFI for my subsequent vehicles since.
The paddle sensor that I had some useful results from was the flowfuel 30L02 from futurlec.com rated at 85 psi ,this sensor has a magnet in the paddle wheel and from memory a hall sensor ,very similar operation to the original zemco sensor.
The data sheet is not exactly correct , but at $10.00 !
Tp

Great 85PSI will cover my current cars, a 93 Chevy TBI at under 20PSI and a 03 Crown Vic with under 60PSi.

It is ideal: https://www.futurlec.com/sensor/flowfuel30l0.shtml

2 Liters is .5283 Gallon per hour

30 Liters is 7.92 Gallon per hour

Ideal would be low reading of 1 Liter which would be around .26 Gallons. There is a good chance it will read lower, just they cannot be 100% sure of its accuracy at that rate.

Which is faintly possible if I can ever get a 100% vapor system up and running.

Per my Scan Gauge II and MPGunio I have seen gallons per hour at idle of around .5, and at cruse around 3 to 6 gallons per hour.

Realistic I can only hope for somewhere around 1 gallon per hour goal.

A good cruse of 35 MPG and 1700 RPMs can run around 2 gallons per.

Thanks.

Rich

cheap fuel flow sensor
 

An internal of the sensor in question ,you can see two 3mm magnets in the paddle crossbar ,normally it comes with one ,i have added the second for better sensitivity, I did at one stage spot mill the the top cover and fit 4 hall effect devices (one magnet fitted) to give more sensitivity , the four outputs were joined together & fed into an mpguino with some success, although low speed was an issue due to sticktion(is that a word?),I did have the engine idle at 15;1 AFR ,cruise ratio 15:5 (2.2 litre 4y toyota),with a larger engine like your Crown you may get better results withe an overall higher fuel demand.
I will have a dig for my notes & post anything else that may be useful.

Tp

They are reported to accurate at .52 a gallon per hour....

So two magnets should cut that to .27 gallons per.

I did not fully understand, did you have to cut into the body to get to the fan to add more magnets??

Are they the two black dots?? Which looked like small allen head screws??

And/OR did you add four hall effect sensors?? That could quad the readings getting down to .1320 or .132 gallon per.

So with two magnets as well, that could lower that to .066 Gallons per...

Well IF I was able to get a system (I do have a plan of one) to run with 100% vapor conversion of the gasoline, then I hope to be using 30% of the fuel normally used, then it is possible to only use .14 a gallon per hour.

This number is based on cursing at 65MPH at 1700 RPMs and normally burning 2 Gallons per hour and IF the claim of needing only 30% of that 2 gallon so 2 times.07= .14 gallon...

So again a totally insane maybe ...Then I might want that low a range...

But I suspect such a count range will be beyond the Zemco system, but at that point I would be most likely happy with a MPGunio OR just add a divide by certain number ICs to lower the range for the Zemco.

So please do share.

Rich

the two black dots are the magnets ,one was fitted when purchased and the hole for the second one was already formed ,can't remember but i had some small cylyndrical magnets from RS or Digikey that fitted (1/8 x 1/8")pushed in with no work.

The rotor sits on a shft with the end sharp like a pencil to reduce sticking from too much surface area drag between the shaft & rotor.


The top of the sensor is held on by four screws sealed with a o ring ,I purchased four sensors units from futurlec over two years & they all were the same.
Initially I tried the two magnets fiitted to the rotor & the original single hall sensor fitted to the lid ,when this showed promise , I machined the lid of a second sensor assy for four hall effect devices & used one magnet in the rotor ,it worked ok except at idle ,where there was not enough fuel flow to rotate the rotor reliably.
I should also mention the Zemco sensor suffered from reading fuel vapour bubbles ,it was almost a full blown r&d project back in the 90's to get around this problem with smaller low flow engines ,this problem wasn't apparent on my 308 & 327 cid engines ,but otherwise the Zemco units were good.

Tp

Great I think I will just add the second Magnet.

Also I believe there maybe some count doubler ICs that might work...

Thanks.

I plan on ordering four as well from the start.


Rich