after reading the searched threads, i've come down to a conclusion. thank god i'm not an EE major. but being a bio major, means i don't understand jack **** about a relay versus a kill switch. a relay sounds much safer, but waaay more complex than a kill switch so i think i will stay with a basic switch [2 wires connected thru a 30A switch]. I have a couple questions that were never answered in the posts as well as some i would like to be clarified.

I have 14 gauge wire, threaded, a 30A switch [12V], and a 1 amp diode.

I am a little confused on where i place the diode. diagrams would be nice...

car---#a---[switch]----#b---fuel pump

does it go in #a or #b? i know it matters which way u put the switch and the diode so which way? maybe i got the wrong switch...it asks me for the power line, something else i forget, and a ground.

does it affect performance w/ a 190lph pump?

 

anyone know where i can find that 1 amp diode? it has to be 12v, right? what if it's 1w 12v?? can it be 11v? and if i can use a resistor, what ohms does it have to be? quite confused..

 

ttt

 

On the fuel pump kill switch, its much easier to just take the ground wire, disconnect it from its stock grounding location (where other wires along with the fuel pump ground meet) at a bolt which gives them the connection.

Just disconnect the fuel pump ground and then extend it to one side of your switch, and ground the other side of the switch. So when the switch is closed, it gives the fuel pump a ground feed and it works, when disconnected, it wont have ground and thus wont work.

This is the safest since you arent running wires of normally "hot" wire. You wont need a diode or anything.

 

>----(+)---->----PUMP---->----(-)---->----(SWITCH)---->----(-)---->----GROUND @ FRAME

 

can anyone else vouch for him? i really want to do this right, i have no clue about electronics.

 

I don't see why it wouldn't work. Just match up wire gauges.

 

match up wire gauges? well, i decided to use 14 gauge instead because i don't want any of the power lost in running thru the current. however, i installed a fuse after the switch in case any surges occur and the fuse will go, not the switch or the fuel pump...

i'd have to say, the basic kill switch is pretty damn easy to install, but matching up all the wires again to blend in with everything...that took a lil more time.

 

I use 12 guage wire for all my electronics. I also have one of those fuseholders which I think you mentioned.

 

The fuse holdes are awesome little things.

Ive stuck them under stereos, behind stereos, under steeing wheels, behind kick panels, behind glove compartments mounted to AC structure, and under seats. Very quick and easy way of getting a fused power source.

 

Sorry to bump such an old post but better than starting a new one (I think).

I'm about to try to install this kill switch tommorow. I purchased 14 gauge black wire, female/male connectors, and a 16 amp switch. I plan on disconnecting where the ground wire connects from the fuel pump and connecting my wire/switch there. This is correct and will work? On the switch, it has two metal pieces sticking out with holes in them. I'm guessing I just put some wire through each hole and twist it around a few times then tape it up?

My last question... people suggest using relays. Is this worth getting or will a regular switch without a relay be just as reliable if you're using a good switch + wire. Thanks!

 

that 16amp switch might not be enough, i believe you need a 30amp. also those holes at the bottom of the switch are to be used so that you can solider the wires on there, i would NOT recomend just sticking the wires through there and taping, they will pull off in no time and then you probally be stuck some where with a car that wont run

 

hm... a 16amp switch might not work or will not work?

What about running a relay? I saw a picture of one, looked like a small black square with 4 metal pieces w/ holes (like on the switch) sticking out. How would I go about installing that?

I was guessing you would connect the switch to two of the metal pieces and the other two would go to the fuel pump wire.


[Modified by Eluzion, 4:55 PM 2/9/2003]

 

i talked with a friend and got a little more info... if you are going to put the switch on the 12v line you definatly need a 30amp switch, but i dont believe so if you just use the switch on the ground that it matters... but what is the price difference between the two switches? if its only a few bucks why not goe for a 30 amp?

as for using the relay... you cut the power line going to the pump, either end of that gets connected to the relay, then another wire from the relay just gets grounded, the last wire goes to the switch... on the switch then, one of the wires goes to the relay and the other just gets grounded.

how it works... when the switch is off the switch wire and ground wire on the relay are not making a circut and keep the relay open. when the switch is on it then completes the circut between the two lines and then completes the power line running to the fuel pump

basicly the relay is safer for running power through, the switch then just controls the relay

if you just run a switch on the power side without a relay, all that power goes through the switch itself

If it were mine i would just run a 30amp switch on the grounded side and call it a day


[Modified by bikeboy80, 12:54 PM 2/9/2003]

 

Yeah I'm going to run it on the ground wire (black). Problem is, I already purchased the switch and it's a 16amp.

I have a solider... but I have no idea how to use it. =/

Anyone wanna give me a quick overview on connecting the 14 gauge wire to the switch using the solider (or however you spell it)? I'm guessing you just sort of melt them together or what? Me = electric newb... unless it's computers.

The solider kit I have, has a big spool of metal wire I'm guessing I use to melt and connect the wire to the switch. It also has some liquid stuff in a tube I think I'm suppose to put on the ends I'm connecting? Thanks.

btw, thanks a ton for your help bikeboy80.


Another thing... I have these tube shaped male/female connectors. I thought you're suppose to put the wire in them and crimp them. Problem is, these aren't crimping very well (plastic). I tried using pliers on the flat part and squeezing them but they don't seem to be crimping, more like breaking. Do I have to solider these too some how?


[Modified by Eluzion, 8:12 PM 2/9/2003]

 

Eluzion, from what I've read, I would not suggest tackling this project for yourself. Read up on soldering all over the web (www.howstuffworks.com, etc.).
Bikeboy80 is correct when he said 16 isnt enough. The pump can easily use 15 amps, its a lot better to have a fuse fail rather than the switch. The fact that the switch is on the normally ground wire has no affect on the current flowing through it. So just because its on the ground, doesnt mean you can use less.
The connectors have to be soldered, there is no other way to get a good connection for this junction. In addition, you also want to use wire ties, double sided tape, or self adhesive wire mounts to secure your wire where ever you run it. Id suggest every 8 - 10 inches.

 

The pump uses only 15. It doesn't go higher than 15 because your fuse under the dash is set at 15. Higher settings can blow the fuse. Or at lease, mine is. I'm using a 20 amp and it's totally fine. YOU DO NOT HAVE TO SOLDER. I used female female connectors and clamped the hell out of them. Since the wiring and switch is out of sight, I'm not worried about it jiggling around because all I do is flip it, and leave. The way I did it you'd need:

2 female to female connectors for the orginal fuel pump wires
4 wire to metal connector [2 for switch, 2 for fuse]\
something to mount the fuse
something to mount the switch
*impt, this is the MOST IMPORTANT THING YOU NEED*
good place to HIDE the switch.

 

don't use 16. use 20 at least.

*edit - make sure u clamp them so they ain't going anywhere. or u can solder. either or, make sure u tape them up after.*


[Modified by all stock, 3:51 PM 2/13/2003]

 

The switch connections must be soldered.
Using any other type of crimp on or slide on crap is not safe. It can fall off after milage since the car has constant vibrations from the road and from the engine itself.