mileage computer for a carbureted engine

[consaka]

Originally Posted by dcb

Just for reference, there's 90840 drops in a gallon (re: IV bottle)

so if I figured this right, at 0.1 gph (small motorcycle idling) we are using 1.6 drops per second. and 10gph=160 drops per second. and 10gph is good for maybe 242hp. So not an easy range to fill accurately and inexpensively.

That of course has always been the problem. let me ask you this though.. How hard would it be to build a circuit board that would allow you to say hook 2 or 3 together on the positive side. In other words say you made a flow sensor small enough for a Motorcycle but wanted to use it on a big block so you hook 3 of these up side by side perhaps with small valve resistance so at high flow rates the other two will open and start working.. now we have 3 sets of signals that will need to be combined to send to the mpguino.
speaking of circuit boards how hard would it be to design this with the 3 inputs and an extra return line input to be subtracted from the others? Im a little weak in the electronics area of design.
Of course im looking at the optical sensor design so thats the type of counting input the circuit board would be sensing. Im thinking perhaps something with a small amp and maybe 555 circuit?

[dcb]

You've seen das Durchflußgeber ?

0.396 gph to 39.6 gph for about $60

Problem is that it doesn't quite get low enough for many idlers. If you put that type in parallel then they will see below .396 and get inaccurate. Parallel drip counters might work (how many drips per second can one count reliably?)

re: 555: a $3 pic can replace a whole army of them.

So is there some physics invloved to limit max drips per second before they change volume or otherwise are better described as a stream?

[consaka]

Originally Posted by dcb

You've seen das Durchflußgeber ?

0.396 gph to 39.6 gph for about $60

Problem is that it doesn't quite get low enough for many idlers. If you put that type in parallel then they will see below .396 and get inaccurate. Parallel drip counters might work (how many drips per second can one count reliably?)

re: 555: a $3 pic can replace a whole army of them.

So is there some physics invloved to limit max drips per second before they change volume or otherwise are better described as a stream?

aye .. I think you might have missunderstood me.. I agree this one is too expensive and doesnt register low enough. to start stacking them you need to start out with something that may already be too low of a flow for the bigger engines. Then you parallel them for the bigger engines.

[dcb]

Hey John, that's an interesting approach. I don't know much about machining stuff, but that pic got me wondering about coefficients of thermal expansion and production.

According to About.com: http://www.handyharmancanada.com/TheBrazingBook/comparis.htm there are some ceramics that have low expansion, possibly ceramics are fuel resistant too, dunno. But not hard to imagine making a mold and baking the parts. Have you ever messed with ceramics? I'm a total nube to the idea, except for pinch pots and stuff Maybe that circulating ball and track can be done that way? I have no idea.

[diesel_john]

The whole idea of this concept flow meter on the last page was to create a flow meter that could be built from home improvement type parts with no power tools but a drill. The concept meter was built with common hand tools. The parts were sanded by hand on a flat surface. The size of the engine determines the size of the ball. The smaller the engine, the closer the fit between ball and groove. If a center bolt is needed an o-ring is used to seal it. Drill a hole in the center bolt if it is used for the outlet connection. The plastic BB toleranted both gasoline and diesel fuel. Type of plastics used would determine the temperature range. Use a light source and sensor to count the ball rotations. Your mileage may vary.

[oldbeaver]

Very, very interesting!

Do you think this device can be used for measuring diesel engine consumption?

I looked at the sketch but cannot figure out how it works. I mean, the mechanic part of it. Once we have a mechanic device that rotates with fuel flow, we may convert that to an electronic signal to be used.

Can you explain a little more your 30 yrs old invention? Where can one get such a device?

Congratulations for this nice work!

Old Beaver

Originally Posted by diesel_john

Let's set a price goal of $30 for this flow meter, that should filter the ideas.

we are talking about non OBD engines.
the marble or epoxy ball is pushed around a circular track by the gasoline.
an electronics guy can tell you to make a light tach to count the ball passes(fuel volume)
the distance is pulses off magnet on the axle or drive shaft u-joint with hall effect or other sensor, a junk yard crank or cam sensor.
the calibration is like any MPG meter, count the pulses per gallon, and the pulses per mile. there are other threads on this site that tell how to use an old lap top to do the computation. but since this is just pulses and you don't have to decipher pulse width, the electronic minded can tell you how to use a divider chip (terminology) and display.

Below a very rough sketch. Visualize this stuff stacked up together and clamped with 4 bolts. The holes thur the outside ring are small enough so the ball passes over. So does some fuel, but it doesn't matter just takes more pulses to make a gallon. Next try to think of materails that are gasoline and alcohol proof to make it out of. A 1/2"x3" aluminum plate and ball mill would be nice, but lets try to think of something even more common and less expensive. Like maybe cut a 5/16" length off a piece of 3" seamless tubing for the outside ring. And 2 1/2" for the inside ring.

[oldbeaver]

Do you know where I can get a couple of these Innovatek flow meters?
Do you remember the price?

Tks.
Old Beaver

Originally Posted by diesel_john

the cam pulley or pump pulley bothe have 6 or 8 spokes in the pullies. and they are steel so would be a good candidate for an old cam position sensor.


The only information regarding resolution is "0.1l/min @ 1000rpm." Might be worth a look...they are cheap enough

How cheap are they? my flow range is 0.1 gal/hr to 3.0 gal/hr.
When i get the two cylinder going the range will be about half that.

[diesel_john]

What I have on my diesel rabbit now is an old Zemco mileage computer. The Zemco flow meter has been restored with a 6mm plastic BB and a red LED light source. And because the diesel sends more fuel back to the tank than it uses, i return the fuel to a very small intermediate tank. i have fuel diagram similar to post 61 bottom diagram. Also see post 84 and 73.

For a diesels that return to the tank, I would think that dcb's computer and two less expensive flow meters would be an easier than what I did, because my system has two solenoid pumps to transfer the fuel to and from the fuel bowl. see post 138

[oldbeaver]

Thank you for sharing this.

I am slow to understand your device. The picture shows the home-made meter very clear. There are three rings and a ball between 2 plexiglass panels. Am I ok?

However, where does the fuel enters and where gets out? I mean, how does fuel move the ball? Why there are three rings? By the way, I imagine the ball is a plastic one, very light. Please correct me if I am wrong.

Looking forward to your explanation...

Originally Posted by diesel_john

The whole idea of this concept flow meter on the last page was to create a flow meter that could be built from home improvement type parts with no power tools but a drill. The concept meter was built with common hand tools. The parts were sanded by hand on a flat surface. The size of the engine determines the size of the ball. The smaller the engine, the closer the fit between ball and groove. If a center bolt is needed an o-ring is used to seal it. Drill a hole in the center bolt if it is used for the outlet connection. The plastic BB toleranted both gasoline and diesel fuel. Type of plastics used would determine the temperature range. Use a light source and sensor to count the ball rotations. Your mileage may vary.

[diesel_john]

been busy but I tried to paint in the ports on this pic.