Fuel pump cutoff switch

[pomfritz]

I’d like to install a fuel pump switch inside the vanagon life console. Looking for a suitable switch to use. I’d like it to be enclosed, ie the back can be stuck to a flat surface instead of having connecting pins showing.

I found something that looks good on Amazon:

JIANFA Car DIY Switch Water Drop Shape Button Switch OFF/ON DC 12V For Fog Lights, DRL, LED Light Bar, etc

(Sorry couldn’t figure out how to copy link)

The specs say it is a 200mA switch. Would this be suitable for the fuel pump?

If not any suggestions for another switch? Should I also use a fuse in the wiring to or from the pump?

Thanks. I was planning on just using a battery cutoff but it would stop the clock each time. Looking for an alternative shut off
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83.5 233K. GW 2.3, SS exhaust, My German Frau named her Stefi

[MarkWard]

If you want to disable the fuel pump with a toggle switch, you will want to disable the fuel pump at the power relay, not the actual pump. The pump could draw up to 8 amps and a cheap toggle won't handle that amount of load.

Looking at the Bentley manual page 97.55 on current track 17 there is a ground for the power supply relay pin. With out a ground, that will disable the injectors and the fuel pump relay effectively without seeing a lot of load. I would install my toggle on that leg.
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Or just ground

[0to60in6min]

installing a toggle switch on the ground side of the pump?

[Wildthings]

It would help if you stated your reason for wanting the switch.

[pomfritz]

Theft protection. I also saw that Bostig is selling a inertial fuel pump switch. Looks like that might work and also get some protection in a crash. Though I wonder what type of everyday bump might trigger it.
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83.5 233K. GW 2.3, SS exhaust, My German Frau named her Stefi

[Wildthings]

I remember an idea of having a time delay which would cut the engine off after a minute or so of running. This gave the perps time to get the car into traffic at which point it would die and they would tend to abandon it, whereas if you just keep the engine from starting in the first place they would be more inclined to spend the time to figure out why it doesn't start.

[MarkWard]

[[email protected]]

^^^
Are you saying the ground has amps running throught it? Isnt the current used by the pump?

[Wildthings]

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^^^^
Ok thanks I need to read up on this. Ground wire at pump is tiny. I would think that a small switch would be sufficient. So if my fridge is using 5 amps are you saying that fuel pump is using more? And are you also saying that if you are putting in 8 amps to a motor there will be 8 flowing out as well? I would think that some of the amps are used as force? Or are you saying 8 amps @ 12v in and 8 amps at 1v out. Thanks

[MarkWard]

What I am saying is that toggle switches are better suited to operating relays. They can be used without a relay, but must be rated for the load they will carry. Most quality toggles are rated for continuous amps at specific volts. As the voltage goes down, the amps go up. No load difference if the switch is in front of the load or after it. There is an advantage to switching grounds with toggles. The consumer will absorb the arch when the switch is opened. This does save the switch contacts, but negligible.
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[Wildthings]

[Paulbeard]

So what's the consensus here? A toggle switch from the fuel pump ground (and if so, how beefy?) or one from the fuel pump relay? I have some open time coming up and this is one of the jobs I was considering tackling but want to tap into the collective wisdom first.
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Currently -> Frida: 87 Tizian Red (mostly) Vanagon GL Westfalia w/ 2.0L ABA conversion
Formerly -> Steward of a 73 Super Beetle (Beater) and 67 Beetle 1300 (Little Max) both names by POs

[dobryan]

Interrupt the wire with the smallest load, the relay ground....
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

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https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
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[[email protected]]

Either hot or ground just use apropriate size wire and switch. I would use ground as at most you are using 8 watts. Ground switched could also be easily reversable.

So hot. 12v X 8 amps =96watts
Ground. .10v X 8 amps = 8 watts

[dhaavers]

^^^ Sorry to say, but your responses here indicate that you are still working on
understanding basic electrical theory. Please stop before someone gets hurt...

Check it: http://www.autoshop101.com/forms/elec11.pdf

- Dave
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86 White Wolfsburg Westy Weekender
"The WonderVan"
<EDITED TO PROTECT INNOCENT PIXELS>

[Wildthings]

[MarkWard]

I suggested what I feel is the proper way to interrupt the circuit in my first post. The electrical diagram is clear which wire to add the interrupt switch to. If you want to still swim against the current, add the toggle you originally asked about to the fuel pump ground wire and see how long it lasts. 6 month updates will be nice. Install the switch in such a way that you can easily bypass it in case it fails.
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[dobryan]

And the problem with fooling with the fuel pump is that when the kill switch fails it will leave you stranded on the side of the road, possibly in a dangerous place. Also makes trouble shooting a pain since you have added another failure mode.
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794