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After a Fluid Flow Sensor...

Something that can do at least 1-2L an hour (really low flow) up to about 15L an hour. Probably an inductive pulse type one similar to this...



Needs to be cheap cheap and capable of measuring fuel...

PM Fury, he had a fuel flow meter in his Vortex, but i think he made it himself, from somethying like a Jaycar kit.

Thanks Gannon, will do. You still after the FSM???

If you wanted to be realy sneaky you can read the injector pulse width from the car's ecu and calculate fuel flow that way.

Or is this for the boat?

MechaWagon wrote: Something that can do at least 1-2L an hour (really low flow) up to about 15L an hour. Probably an inductive pulse type one similar to this...

nah, apparently hes up to some other mischief .....

Nah Ben iv sorted out the wiring, thanks anyway.

Peejay, thats a mighty clever suggestion

PeeJay wrote:If you wanted to be realy sneaky you can read the injector pulse width from the car's ecu and calculate fuel flow that way.

Or is this for the boat?

Yeah, the boat. Navman fuel meter might be a better option though...

A lot of the new car trip computers and aftermarkety ones count pulses too.

I made a flow rate sender, by 3 layers of ABS plastic bolted together.
The middle section had a holeabout 35mm, a rotor ( shaped like a paddlewheel to just get to the edges of the hole) a central spindle (about 2 / 3 thou larger than the thickness. 2 tiny magnets ( if only 1 , it is unbalanced) imbedded in the rotor and a hall effect sensor lined up with the magnets on the outer cheek. The centre section also had 3/8 copper pipe inserted along the tangent to the hole, so that the flow runs through the tube, skims the paddle wheel ( which turns it ) and exits on the same tangent.

Glue 1 cheek to the centre section
use a thin gasket paper for the other side and bolt it together, so it is "fuel proof"

Cost ABS derlin plastic scraps - $2 at a plastic / perspex place
hall effect sensor $ 4.45 Jaycar ZD1902 ( will need power supply from meter of 4.5 - 6V)
a few ss bolts $2
Glue and sundry ( pipe, gasket, ss axel pin etc) $3

You can also vary the rate of count with an electronic speedo adjuster, but this setup as is, will at least give you a pulse.

PM me if you want full details. I looked and looked and couldn't find anything under $80

Cool, thanks for that.

How did you make the paddle?

It wasn't as complicated as it is going to sound....

A circle of larger diameter of the centre section hole, where the paddle wheel will fit, ( same thickness) then scribed a hole the same size as the main hole, in the middle section.

I set up a drill bit in a drill stand ( around 5/16 th from memory)

I "pinned" the axel to a timber support, and drilled holes so that the centre of the hole, aligned with the scribe mark, about 2 mm apart.

I calclated the exact distance of drill dia and spaced the exact distance in between the holes. ( sound confusing ) basically hole, space, hole , space etc and when calculated, there is the correct distance for the last hole and space .

Rotate the disk on the pin, till all holes are drilled.
Cut through on the outside of the scribe mark and clean up , while spinning, on a linisher. looks like a fat, bicycle gear sprocket.

I also drilled the 2 magnet holes on the spindle.
cleaned up the "hole" edges with a fine round file.

This fits neatly in the hole, if it doesn't spin it on the linisher a touch more. It needs to be able to spin freely, on its axel. The thickness of the gasket paper is enough clearance, along with the axel, being fractionally thicker than the material thickness and paper together.

The first one I did, the dia of the holes was too small. I was using 3/8 tube, so needed to get a larger than 3/8 hole, as only 1/2 the dia is being used for the outside of the paddle wheel. 5/32 was enough for my needs.

When clearing it on assembly, I blew compressed air through it and it whistled like a top. Plenty of volume.

I got the idea from a wind measuring device. ( totally different in construction and not electronic, but the wind pressure was incremented by a "wind wheel" I had it hooked up to a fuel flow led display ( which, the whole thing has gone missing after my EJ20 conversion Damn ! )