Clone Electric Start Electric Fuel Pump

[bob58o]

Total Newb to Relays and suck at electronics.

Looking for a way to wire a 12V 1 amp fuel pump so that it turns on and off with the ignition key. That seems easy. A 12V SPST 4 Prong Normally Open Relay should do that.

There should be a wire from the ignition key box thing to power the relay right? What wire do I use?

Ideally, I'd also like the pump to turn off if I kill the engine via remote wired kill switch on handle bars or something. Is there an easy way to accomplish those simple needs?

 

[ezcome-ezgo]

The fabulous yellow wire?

 

[anickode]

If there is a 12v contact on the ignition switch that is closed when in the run position, that's where you will grab your power. If it doesn't have one, you will have to find a lawn and garden ignition switch for a riding mower or something that has a magneto ignition and headlights. It will need the ignition contacts completely separate from the 12v components.

The factory wiring (notice I said wiring, not ignition switch) does not appear to have a 12v lead switched by the run position however. Only a momentary 12v for the starter solenoid. The "run" position contact will be closed in the "off" position and open in the "run" and "start" position, as it is used to ground out the P lead when the ignition is shut off (just like a normal kill switch) and is not part of the 12v circuit, and neither is the yellow wire that goes to the oil sensor.

It's not like a car where the ignition runs off 12v. The ignition switch is just a coil grounding kill switch with an extra set of contacts to turn the starter motor on and off. Everything ignition, oil sensor, and kill switch related is exactly as it would be on a pull start model.

Do do your remote relay, you will need a relay that replicates the function of the ignition switch, minus the starter motor.

So you will need a relay that has NO and NC contacts, so a DOUBLE throw relay. (Will likely be an 8 pin relay unless you find one that is just NC on one side and just NO on the other.) NC will interrupt the P lead, and the NO will interrupt the power to the fuel pump. When the relay is energized, it will run. When the relay is de energized, it will kill power to the pump and ground out the ignition coil.

 

[TT540]

^ he said do do.

Another way is to have a single simple $5 switch on the handle bars that is the "RUN / OFF" switch. This switch will be double pole double throw. Meaning it is two switches with one actuator. No relay needed. Each pair of switch contacts will do the following:

1) Switch contact pair one will serve to provide power to the fuel pump when in the ON position. No relay needed for most any switch other than a micro tiny switch. The path is (+12V battery)----(Fuse)----(Switch)----(Fuel Pump).

2) The other contact pair will serve to cut off a running engine. The switch in the OFF position will ground the yellow wire. The path is (-neg bat gnd)----(switch)----(yellow wire). there is no direction.

To summarize. Get a DPDT switch.
Switch in the ON/UP position sends twelve volts to the pump, and the the yellow wire is "open" and engine runs.
Switch in the DOWN/OFF position removes 12 volts from pumps, and then applies GND to the yellow wire.

I can draw up how to do this when you select a switch. "picture schematics" work a lot easier for most folks. I can help you find the right switch. What are your physical preferences? rocker, toggle, circle hole, square hole...

---------- Post added at 09:13 AM ---------- Previous post was at 08:35 AM ----------

I would suggest this switch be illuminated so that you do not stall out, and accidentally leave the full pump running. but not a must have. I probably have a switch you can use.

 

[anickode]

It doesn't make sense that there would be 12v fed to the ignition coil.

 

[TT540]

Oops. I'll edit that away.

 

[bob58o]

So I can wire a switch that has a line from the battery+ to the fuel pump AND a line from the "yellow wire" to ground.

In one position, the "yellow wire" circuit is OPEN and the Pump circuit is CLOSED?
Pump is pumping and spark is sparking.

In the other position the "yellow wire" Circuit is CLOSED and the Pump circuit is OPEN?
Pump is not Pumping and the Spark is not Sparking.

 

[TT540]

Correcto mundo.

 

[bob58o]

Cool.

We're going to be like three little Fonzies.
Come on Yolanda, What's Fonzie like.

 

[bob58o]

^ he said do do.

Another way is to have a single simple $5 switch on the handle bars that is the "RUN / OFF" switch. This switch will be double pole double throw. Meaning it is two switches with one actuator. No relay needed. Each pair of switch contacts will do the following:

1) Switch contact pair one will serve to provide power to the fuel pump when in the ON position. No relay needed for most any switch other than a micro tiny switch. The path is (+12V battery)----(Fuse)----(Switch)----(Fuel Pump).

2) The other contact pair will serve to cut off a running engine. The switch in the OFF position will ground the yellow wire. The path is (-neg bat gnd)----(switch)----(yellow wire). there is no direction.

To summarize. Get a DPDT switch.
Switch in the ON/UP position sends twelve volts to the pump, and the the yellow wire is "open" and engine runs.
Switch in the DOWN/OFF position removes 12 volts from pumps, and then applies GND to the yellow wire.

I can draw up how to do this when you select a switch. "picture schematics" work a lot easier for most folks. I can help you find the right switch. What are your physical preferences? rocker, toggle, circle hole, square hole...

---------- Post added at 09:13 AM ---------- Previous post was at 08:35 AM ----------

I would suggest this switch be illuminated so that you do not stall out, and accidentally leave the full pump running. but not a must have. I probably have a switch you can use.

You say double pole double throw, but the links in the PM are SPST?
How many wires do I need coming out of the switch?

If you could draw me a picture I would appreciate it.
Something like a lighted rocker switch (or anything).

 

[TT540]

Sorry for the confusion. The links in the PM will not work becauze they are SPST. But they are freakin hilarious! I mean a switch with a stripper dancing as the label... shut the front door!

The switch you want will have 6 terminals. 3 per "side" or pole. You will only use 2 of 3 three contacts per side. I will sketch it up tomorrow while at a computer.

 

[bob58o]

OK I think I'm starting to get it.

So it seems I need a 2 position, ON - ON, 6 pin, DPDT switch.
Or a 3 position ON - OFF - ON, 6 pin, DPDT switch

I'd prefer the 2 Position Switch.
The 3 position switch (if switch to the middle position would kill the pump, but not the engine).

INPUT 1 has OUTPUT 1RUN and OUTPUT 1KILL
INPUT 2 has OUTPUT 2RUN and OUTPUT 2KILL

Input 1 is yellow wire
Output 1RUN is left "Open"
Output 1KILL is connected to ground

Input 2 is from the Batt+
Output 2RUN is to the Pump
Output 2KILL is left "open"

When switch is set to RUN...
Yellow wire circuit is OPEN
Pump wire circuit is CLOSED

When switch is set to KILL
Yellow wire circuit is CLOSED
Pump wire circuit is OPEN

https://www.amazon.com/Power-Rocker-Switch-DPDT-30-10082/dp/B000LDV59Q
Power Rocker Switch - DPDT / On - On : 30-10082

EDIT:
Changed my mind.
In case I want to let the carb bowl run dry, I think I would like a 3 position ON-OFF-ON switch.

So my search is now.

DPDT
6 Pin
3-Position
ON-OFF-ON
Waterproof

 

[bob58o]

This DPDT 6 pin, Three Position, ON-OFF-ON, Waterproof Rocker Switch for Fuel Pump / Ignition Kill Switch.
https://www.amazon.com/gp/product/B001PNMBLM/ref=od_aui_detailpages00?ie=UTF8&psc=1

This SPST, Two Position, ON-OFF, Waterproof, Rocker Switch for HeadLight
https://www.newegg.com/Product/Product.aspx?Item=9SIA1N63ME6792

This switch housing..
https://www.ebay.com/itm/MicTuning-...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

 

[TT540]

Dude. Job well done on the schematic and the idea of a 3 position switch to let the carb bowl run dry.

Just so you know, the switches you are looking at are pretty big in size. Just consider that and the attachment/mounting solution before you order a switch. Great for access and actuation, but maybe an eye sore for a "mini" bike.

Pro tip: When it comes time to install the switch, make sure your orientation is correct for which side is up/run before you snap it into place. Switch can fool you unless you have taken one apart. When the toggle is pushed "away" from you, it is the pair of contacts CLOSEST to you that are actually closed.

---------- Post added at 06:55 AM ---------- Previous post was at 06:21 AM ----------

After some digging, I found the following as an option:

https://www.amazon.com/dp/B01ARJEHUW/ref=psdc_404724011_t3_B071HTWJ6K

Configuration would be:
red button = Kill Switch
Small toggle = headlight
Large winker = Fuel Pump (right on, left off) though I am unsure if this is momentary or not...

Drawback is I cannot find a Double Pole switch in any of these combined handle bar solutions. Winker switch FTW. I never realized switches could be so fun.

---------- Post added at 07:11 AM ---------- Previous post was at 06:55 AM ----------

What switch is going to start the engine? perhaps this solution would be good:

https://www.amazon.com/Motorcycle-H...rd_wg=63KMX&psc=1&refRID=TC66FKZEV6EQ2G7S364T

 

[Texan]

Are you keeping the control key box shown in first post? To keep it simple, you can run constant + to the fuel pump and then use a simple toggle switch to send the neutral.

 

[TT540]

Are you keeping the control key box shown in first post? To keep it simple, you can run constant + to the fuel pump and then use a simple toggle switch to send the neutral.

By doing it this way, you can use a SPDT switch! The common middle post (#3) on the switch would go to Ground/Neutral/Chassis.
Post 1 goes to the Pump's negative (-) connection.
Post 5 goes to the kill switch yellow wire.

With this, you can now use the other more simple handle bar switch like this one:

https://www.amazon.com/Motorcycle-H...=1526566551&sr=8-15&keywords=handlebar+switch

Red switch up = fuel pump on
Red swtich middle = does nothing (starves the carb to dry)
Red switch down = kill coil.

Green switch up = headlight on
Green switch down = headlight off.
*this green switch can illuminate with the key-on position, head light on, or not at all.

 

[Whitetrashrocker]

Keep this conversation up and Bobs gonna start digging on logic control electronics.

 

[bob58o]

If Bob is already sick of switches = TRUE

AND

Bob has already ordered switches that he no longer wants = TRUE

THEN

Bob is going to order another switch

AND

Look into Push Button Start as Well (and maybe a horn - cause why not)

So I'll probably be looking for some Momentary Switches too.
Too many switches, too many options LOL


Thanks so much.
I like the handlebar switch!
So on the above switch, the third wire on the green light? Is that for the light inside the switch? If not needing a light, then I just use the two leads?
If wanting it to illuminate the switch when the headlight is on, then I just tap into the 12V headlight circuit to signal the light on the switch?

 

[Whitetrashrocker]

Simple way to do it.


What's the fuel pump rated at amperage wise?
Gotta make sure switch will handle it. If not then use a relay.

 

[Whitetrashrocker]

Also the fuel pump is just a vane style I believe. If your tank is higher than the pump will the gas leak through the pump and into the carb?