Can I install a kill switch on my truck?

I've looked up a kill switch made by 41twentytwo called the Drop-in Kill Switch, but the years only go down to 1999 and I need one for my 1986 F-250. It's a relay bypass that is described as;

HOW IT WORKS:

1. Our custom Relay Bypass Module replaces your vehicle’s factory Starter Relay (or optionally your Fuel Pump Relay).
2. Hide the wired included Toggle Switch (or use your own toggle/pushbutton) OR the Wireless Remote Switch somewhere in your vehicle only you know. With the Kill Switch activated, your vehicle will not start.
3. That’s it!

What is included in the kit:​

• Control Junction Box
• Relay bypass module
• Pushbutton Switch in Wired Version (OR) Two Wireless Remotes in Wireless Version
• Wiring Harness
• Wire Connectors

Have you used any other types that would work for my 1986 F-250 6.9L IDI?

Seems like it'd be simple enough to wire in a switch to prevent the fuel safety shutoff valve from opening (which happens when you turn the key on).

It might, but I'm not educated in that. This one replaces the Relay Fuse in the fuse box and it appears my truck (1986 F-250-6.9L) doesn't have that fuse, though I'm not positive

Brian VT said:

Seems like it'd be simple enough to wire in a switch to prevent the fuel safety shutoff valve from opening (which happens when you turn the key on).

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Maybe just disconnect the factory connector at the IP and wire in a new circuit tied to a switch tucked under the dash? By creating a separate circuit it would be easy to go back to the original factory setup should there be a need to.

"Maybe just disconnect the factory connector at the IP and wire in a new circuit tied to a switch tucked under the dash?"

The IP?

Old-Red said:

"Maybe just disconnect the factory connector at the IP and wire in a new circuit tied to a switch tucked under the dash?"

The IP?

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There is a wire that goes to the injection pump. There is a valve there that is closed when it does not have power. It prevents fuel from going to the injection pump (probably to prevent fuel spills in the event of an accident or other failure?). It opens when you turn the key on.
It seems you could just wire a switch inline this wire to control if the shutoff valve is open or closed even when power is being sent to it. Just like a light switch in your house.

Several ways this can be done. You could install a switch that would open the start circuit at the starter relay on the right fender. You could install a switch that would open the circuit to the fuel shut off solenoid on the fuel injection pump. Both easy to do, both easy to bypass if someone is wanting your truck.

Same sort of idea but break the power feed that supplies power to the key switch. Much harder to figure out quickly what is going on.

Keep in mind any system can be figured out and worked around, the idea is just to slow them down and get them to move on. I would think what you asked about would work if you use it to bypass starter relay.

Mine already would slow down a thief. Manual glow plug controller and manual starter button. But we don't get many truck thieves around here.

If you have a manual transmission...... no one's gonna steal it...... if its an odd ball truck like say......idk.... a 1986 ford diesel, no one's gonna steal it..... now, if you drive a 2015 White Toyota Taco.......everyone is going to steal it...... but yeah, put a switch on the shut off solenoid........

Brian VT said:

Mine already would slow down a thief. Manual glow plug controller and manual starter button. But we don't get many truck thieves around here.

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If you were driving anything common, you'd have a case for concern...... theres no value in our old junk except to us bunch of weirdos....

A. That harness will not work on your '86.

B. If you are that worried about car theft, buy a mid 20 teens Honda from your local police auction and leave it out as a decoy, preferably with an air tag in it. No proper thief will come with in a Nautical mile of your '86.

A co-worker of mine's son had his 6.0 F250 at a repair shop getting (surprise, surprise) the motor rebuilt. The shop had pushed the chassis back out side after removing the engine while they completed the rebuild on the stand. One morning they noticed the side window was busted out on the truck. Upon reviewing the surveillance video, the watched a "thief" roll up and bust out the side window. He popped the door, climbed in and tried his hardest to get that truck to start. After pulling a bunch of wires out of the dash and not having any luck getting it to start..... He bailed and ran for the hills, most likely disappointed that he couldn't nab that "lifted" F250.

Moral of the story: You aren't trying to fend off rocket scientists. Don't over complicate things.

Maybe he wants a kill switch to stop a runaway engine? (by shutting off the fuel supply)
Not a bad idea. I don't know how often that happens or what causes it.

Brian VT said:

Maybe he wants a kill switch to stop a runaway engine? (by shutting off the fuel supply)
Not a bad idea. I don't know how often that happens or what causes it.

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I think thats basically impossible, because the top cover would have to be put on wrong to cause that...... thus the shut off wouldn't work anyway........ unless theres another "run away" opportunity that I dont remember......not saying you're wrong.... but im not sure your right either....

FrozenMerc said:

A. That harness will not work on your '86.

B. If you are that worried about car theft, buy a mid 20 teens Honda from your local police auction and leave it out as a decoy, preferably with an air tag in it. No proper thief will come with in a Nautical mile of your '86.

A co-worker of mine's son had his 6.0 F250 at a repair shop getting (surprise, surprise) the motor rebuilt. The shop had pushed the chassis back out side after removing the engine while they completed the rebuild on the stand. One morning they noticed the side window was busted out on the truck. Upon reviewing the surveillance video, the watched a "thief" roll up and bust out the side window. He popped the door, climbed in and tried his hardest to get that truck to start. After pulling a bunch of wires out of the dash and not having any luck getting it to start..... He bailed and ran for the hills, most likely disappointed that he couldn't nab that "lifted" F250.

Moral of the story: You aren't trying to fend off rocket scientists. Don't over complicate things.

Click to expand...

Id totally steal your truck....... if you're truck is ever stolen, keep this post bookmarked, because itll explain to the police why your pretty red truck is in hidden behind my barn.....

Brian VT said:

Maybe he wants a kill switch to stop a runaway engine? (by shutting off the fuel supply)
Not a bad idea. I don't know how often that happens or what causes it.

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There are two failure modes that cause a run-away. The first is when the engine starts consuming it's own oil, and this can happen on any style of diesel engine. The oil can come from a bad turbo seal, valve seal, or other damaged component (CDR or crankcase breather) that allows oil to get into the intake track. This is the only run-away mode an IDI is susceptible too, and cutting fuel won't stop this type of run-away. You have to kill the air supply to the engine.

The 2nd mode is when an injector hangs open. This failure mode typically only occurs on engines that have unit injectors, and 2 stroke Detroit's are especially prone to this due to the design of the fuel metering rack. But, it can also happen on common rails or HEUI's when the injector tip becomes damaged and the engine starts fire hosing fuel into the cylinder since one injector now allows fuel to enter under much lower pressure than the rest and all the fuel flow goes to the low pressure point. Due to the way a mechanical injection pump operates, If an IDI (or any other mechanically injected diesel) blows an injector tip, it will almost always end in a hydro-lock, and not a run-away.