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fuel pump cutoff switch

S

sixditch

NAXJA Forum User
Location
Snellville GA
I am getting ready to install a fuel pump cutoff switch on a 98, just wondering if anyone knows which wire to cut. (I don't want to cut the ground, I want to cut the power/ignition wire) I know it's not the same wire colors as earlier models.
Please help
thanks
 
I run two kill switches, one for the ignition, one for the starter, very far apart, undetectable. Even if they found one, only half their "job" is done. At least two, I feel, are mandatory. It would be an idea to disable the fuel pump, too. Three would really drive 'em nuts.

I toyed with the idea of installing a easily-found "decoy" connected to a few radio shack piezos' in the cab that are laying around the garage, but have so many other more important projects/maintenance issues, its' way down on the list.

btw, am almost finished installing a Viper remote start/door opener, so if I want to use it, say at work where its' safe (but cold n the winter) the switches are moot.

sv
 
Not trying to hijack the thread or anything, and it may sound kind of retarded but once I finish a project I like to know for sure it works. Will it damage anything to kill the fuel pump while the engine is idling?
 
Dvipercop said:
Not trying to hijack the thread or anything, and it may sound kind of retarded but once I finish a project I like to know for sure it works. Will it damage anything to kill the fuel pump while the engine is idling?
Click to expand...

If you install a fuel pump kill switch, an easy way to check it is to flip the switch and try cranking it. It may run for a second or two on gas in the lines, but not long. Don't test it too much or you may kill the pump.
If you flip the switch while idling it will cut the motor off(if you wired it right). I'm sure if you do it once or twice it won't hurt anything.
 
Dvipercop said:
Not trying to hijack the thread or anything, and it may sound kind of retarded but once I finish a project I like to know for sure it works. Will it damage anything to kill the fuel pump while the engine is idling?
Click to expand...
No
 
One more thing to ponder, just remembered. Last August I ran out of fuel but it turned out the sender went bad on my '98 and I thought I still had about 1/4 of a tank left.

In +90* temps w/dual Optimas I must have cranked a dry fuel pump for five - ten minutes, easily. Was told by numerous individuals, including my friend the parts manager at Jeep and a respected forum member that lack of fuel in the tank probably overheated the pump motor and possibly significantly shortened the life of the motor.

I still have not reinstalled the skid plate and a few days ago priced a new oem pump out the door w/my discount at about $313. I need a reliable xj to run from Long Island, NY to northern NH on a regular basis, have no choice but to replace the pump for "insurance" sake.

Maybe interrupting the ignition wire is a better bet...

sv
 
mikeny59 said:
One more thing to ponder, just remembered. Last August I ran out of fuel but it turned out the sender went bad on my '98 and I thought I still had about 1/4 of a tank left.

In +90* temps w/dual Optimas I must have cranked a dry fuel pump for five - ten minutes, easily. Was told by numerous individuals, including my friend the parts manager at Jeep and a respected forum member that lack of fuel in the tank probably overheated the pump motor and possibly significantly shortened the life of the motor.

I still have not reinstalled the skid plate and a few days ago priced a new oem pump out the door w/my discount at about $313. I need a reliable xj to run from Long Island, NY to northern NH on a regular basis, have no choice but to replace the pump for "insurance" sake.

Maybe interrupting the ignition wire is a better bet...

sv
Click to expand...

hmmmmm...
you got me rethinking this mod and maybe doing the ignition kill switch instead.

Where did you tap into your ignition wire? (what color is the wire?)

Any info. would be great! Stolen rig stories are getting too close to home.

thanks
 
Well I got the fuel pump shut-off switch all done, but now I'm intrigued by the idea of an ignition kill switch as well. Sixditch already asked, but I spose I'll ask again. What would be the best place to splice into the ignition wiring? What are we looking for?
 
Dvipercop said:
Well I got the fuel pump shut-off switch all done, but now I'm intrigued by the idea of an ignition kill switch as well. Sixditch already asked, but I spose I'll ask again. What would be the best place to splice into the ignition wiring? What are we looking for?
Click to expand...
I put a tip-over switch in mine that kills everything if the dirty sides up.
 
For the starter kill I literally ran 10 gauge through the fiewall and interrupted the wire running directly to the solenoid - and used a heavy switch rated for the circuit. I was lazy but it worked.

Give me 'til tommorrow a.m. to fish through my fsm and I'm sure I'll find the page/schematic on which wire I interrupted for the ignition.

Fwiw I'm in the process of installing a Viper remote start, according to their generic instructions - and they're correct - most of the wires can be found bundled nicely in the steering column. I can't remember the color, but I believe the ignition wire shows B+ when the key was in the run AND start position, dropping off a couple of hundredths of a volt when cranking.

I used a test light, but the manual said use a digital multimeter or risk whacking out the cpu, I didn't bother though.

sv
 
mikeny59 said:
For the starter kill I literally ran 10 gauge through the fiewall and interrupted the wire running directly to the solenoid - and used a heavy switch rated for the circuit. I was lazy but it worked.

Give me 'til tommorrow a.m. to fish through my fsm and I'm sure I'll find the page/schematic on which wire I interrupted for the ignition.

Fwiw I'm in the process of installing a Viper remote start, according to their generic instructions - and they're correct - most of the wires can be found bundled nicely in the steering column. I can't remember the color, but I believe the ignition wire shows B+ when the key was in the run AND start position, dropping off a couple of hundredths of a volt when cranking.

I used a test light, but the manual said use a digital multimeter or risk whacking out the cpu, I didn't bother though.

sv
Click to expand...

thanks
 
mikeny59 said:
Was told by numerous individuals, including my friend the parts manager at Jeep and a respected forum member that lack of fuel in the tank probably overheated the pump motor
Click to expand...

Yes, but this is because you cranked it over and over--with the fuel pump running--when the tank was empty. That's not a good thing to do. That is completely different, however, from cranking it over and over when the fuel pump is NOT running and/or when there's fuel in the tank.
 
Right you are, d-man.

And I bet/hope any miscreant worth his I.Q. would quit cranking the starter motor within fifteen seconds or so before realizing he's been hoodwinked :laugh3:

I know I did, but I had to learn that in juvy :gag:

Ignition circuit seems the best still, nothing to wear except the switch.

Still intrigued though by those devices that lock the pedals together, anybody's garage must have enough scrap metal to make one.

sv
 
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