Kill Switch

[Mikes91]

Got a bit of time and dollars in my truck and have been thinking about trying to fend against potential fires by installing a kill switch immediately after both batteries, before power goes ANYWHERE.

Can anyone comment on how this could be done? I'd use the switch any time I was not in the truck for more than a few minutes. I've seen at least one car smoking in the parking lot due to a stuck starter (FD got it out) and am aware of many dash fires in these '87-'91 Ford trucks and even up to the '94 model year.

I don't mind resetting my clock or driving with it wrong, but I'd sure mind if my truck became toasty fried--especially if that Cummins "610" goes in it next year.


Mike

 

[wwwabbit]

Well, a constant duty solenoid would do it... from there I would suggest starting a second "hot all the time" fuse panel. You might be able to get away with using an ign. circuit on an alarm to trigger the solenoid. Then have the alarm on the "always hot" fuse panel. When you arm the alarm it turns off the solenoid (like it would disconnect the ign.) and then when you get back to the truck and disarm it, your power is turned back on. Plus it would give you some security.

The biggest part is going to be the constant duty solenoid that can take the amperage that you are going to be putting through it.

 

[L.Wilkinson]

Got a bit of time and dollars in my truck and have been thinking about trying to fend against potential fires by installing a kill switch immediately after both batteries, before power goes ANYWHERE.

Can anyone comment on how this could be done? I'd use the switch any time I was not in the truck for more than a few minutes. I've seen at least one car smoking in the parking lot due to a stuck starter (FD got it out) and am aware of many dash fires in these '87-'91 Ford trucks and even up to the '94 model year.

I don't mind resetting my clock or driving with it wrong, but I'd sure mind if my truck became toasty fried--especially if that Cummins "610" goes in it next year.


Mike

Had a friend route his battery cables up to a manual disconnect switch, the turn handle of which was accessable under his driver seat, cables and switch under the floor boards. This would be your traditional class 8 truck battery knife switch, Cole Hersee, etc.
His reason was as a theft deterent, but it would do the job your interested in without any fancy circuits.

 

[MIDNIGHT RIDER]

We service the local ambulance fleet at the shop I work at.

They have the battery cables routed to underneath the driver seat.

Under the driver seat, on the area between the seat and door, is a big rotary knob.

The switch is under the floorboard, outside the cab; and the stem protudes through the floorboard, into the cab, to the knob.

To preserve clock and radio memory, there is a small fused wire that feeds them.

The ambulance employees must turn off the switch every time the vehicle is parked unnattended.

It is also a pretty good theft deterent; because the uninitiated would not know to turn the switch.

In my area, when the year models of your truck were new, there were several Ford automatic trucks burned to the ground.

Not because of electric problems, but because of plastic transmission lines rupturing and spraying hot transmission fluid all over hot manifolds under high pressure.

We had three burn the same week.

The battery switch is a good idea; as there have been many barns burned due to tractors shorting out. I caught my own just in the knick of time a few years back. I got by with only losing the wiring harness. I could have lost a new barn and everything in it.

 

[Agnem]

The marine industry offers a good selection of battery switches. However, I don't know how many of these are going to come close to carrying the kinds of amps that you need. 500 seems the common max, and you really need 2000, don't you?

 

[highest_vision]

Caterpillars use keyed master switches, and they use them on equipment that would be sending more amperage to the starter than our trucks ever will! This way you'd have your fire protection and theft prevention
James

 

[JPR]

How about a Stancor 586-902 ?

 

[Mikes91]

As these posts have indicated... amperage is key. I don't know what kinds of amps are going where. Batteries are 1000 CCA... I assume the switch would have to handle the max amperage the batteries would deliver in tandem, so 2000 CCA.

I also assume the circuit is dealing with far less than 2000 amps in normal operation (when not cranking the engine).

Mike

 

[Mikes91]

Had a friend route his battery cables up to a manual disconnect switch, the turn handle of which was accessable under his driver seat, cables and switch under the floor boards. This would be your traditional class 8 truck battery knife switch, Cole Hersee, etc.
His reason was as a theft deterent, but it would do the job your interested in without any fancy circuits.

Why not something like this: http://www.jcwhitney.com/autoparts/...Id-100000205696/Pr-p_CATENTRY_ID:100000205696

The marine switches were much lower amperage. I don't know if the 500A constant duty limit on this switch is an issue... not sure what operating load our trucks carry. The 2500A capacity would be fine for starting, looks like.

 

[JPR]

Continous should be less than a 100 amps since that is what our alternators are rated at and any more than that would be draining the batteries.

 

[Mikes91]

True...

 

[kennyd]

I think the majority of the Ford truck fires where from the headlight switch. They are very prone to heating up and catching fire, especially when a bunch of extra lighting is added to the truck, or towing a trailer with a bunch of lights that are connected to the stock lighting circuit on the truck.

The well spoke of "headlight mod" will take the most load of the headlight switch, and can be done for very little money. Also having all accessories wires through a rely fed straight from the battery will get any extra loading off the stock wiring, which is not meant to handle any more than the factory installed items.

Running battery wires under the truck to inside the cab is also a risk, as a small nick in a wire would lead to a instant meltdown, or a careless mechanic prying against the wire while working on something else... Plus, with the price of the switch, cables and proper connectors this would be a very pricey venture...

Just my opinion...Its worth what you paid for it

 

[Mikes91]

I think the majority of the Ford truck fires where from the headlight switch. They are very prone to heating up and catching fire, especially when a bunch of extra lighting is added to the truck, or towing a trailer with a bunch of lights that are connected to the stock lighting circuit on the truck.

The well spoke of "headlight mod" will take the most load of the headlight switch, and can be done for very little money. Also having all accessories wires through a rely fed straight from the battery will get any extra loading off the stock wiring, which is not meant to handle any more than the factory installed items.

Running battery wires under the truck to inside the cab is also a risk, as a small nick in a wire would lead to a instant meltdown, or a careless mechanic prying against the wire while working on something else... Plus, with the price of the switch, cables and proper connectors this would be a very pricey venture...

Just my opinion...Its worth what you paid for it

I assume running wires to the cab would require heavy duty conduit to protect the wires against oopsies. I'll be checking into the headlight switch mod.

Also have an alarm system I wish I could remove from the truck... Have no idea how to do it. It is one of those Viper systems from the early '90s... doesn't work, but still wired in.


Mike

 

[160k87F250]

What about wiring a switch on the pigtail that goes from the r/s positive battery terminal to the starter solenoid. There wouldn't be that many amps going through that circuit, and it would kill all power to the truck except the battery cables going to the starter. It's unlikley a fire would start at the starter, and with all other power cut off to the truck, it would be a good anti-theft device.
John H