FYI-Fuel pump-6v electric

[bob_amos]

Safety switches do come as standard equipment on newer vehicles. The computor has a few second prime when the key is turned on pressurize the system. Then once the engine oil pressure comes up the pump relay is activated by the computer. But this safety device is not to protect an engine with low oil pressure. It actually is a device that the computer watches. If the car is in an accident and the engine stops the pressure will drop and when the computer sees no RPM and no oil pressure it turns off the shut down relay so as not to feed a possible fire. I can see where wiring one of these into our cars to protect against no oil presure might be of interest. But try to resist that idea as a vehicle that is running in traffic that looses oil pressure could cause the vehicle to stop in an unsafe manner. This might end up in someone's life being at jeperdy. I'd prefer an engine developing a knock than loosing my or someone elses life. Ya gotta always think safety. An engine can be replaced but a life cannot.

[Plymouthy Adams]

the computer fires the pump to pressurize the fuel system...the pump is then controlled by the presence of ignition..no ingition to burn the fuel in the cylinder..no pump...engines with distributorless ignition must wait sometimes up to two full engine turns for the computer to sync the cams sensor signal with the cransk position sensor so to fire the correct injector and spark plug...this is the same with a single coil..coils that split between two cylinders or the most prevelant today..one coil per cyclinder directly on the plug.. as for accidents..todays cars are equipted with roll over valves that does shut off the fuel..you would be surprised at all the people in denial that thaink when a fuel pump quits working, that the roll over valve has failed...maybe..but gravity will fail first...

[Normspeed]

Bob, I think the idea of using oil pressure has the same goal. If the motor stops running (due to a crash) the oil pressure drops and the fuel pump shuts off. I see what you mean about the low pressure possibly causing a stall though. For me, I'll take my chances without the safety cutoff.

I do like the idea of hidden or camoflaged kill switches, to deter theft. The car runs til the carbs are empty then shuts off, hopefully in traffic. The thieves, rather than start searching for a cutoff switch, leave the car and get outta the area before a helpful policeman stops to assist.

It's fun thinking up ways to hide one or more cutoff devices.

[bob_amos]

Todays cars do mostly have a roll over device of some type. Vehicles of just a few years ago did not have such devises and used the lack of RPM coupled with the lack of oil pressure to shut things down. Ford, as much as I hate to admit, was the early leaders in a collision/roll over valve use. The problem with theirs was if you hit the valve with something like a foot or vacuum cleaner the valve/switch tripped. Most people did not read the maunal to know it was there. The local car wash tows lots of cars to our shop to reset the valves/switch. They just cannot seem to understand what I tell them about these valves. These are actually good devices to retrofit to any car and are not voltage sensitive.

[old woolie]

Had a couple of Fords towed into the shop where I used to work with those switches tripped. Right after one of those big thumpin' sub woofers was installed next to the switch in the trunk.

[bob_amos]

Really? I haven't seen that one yet but the guys and myself have actually joked about that happening. We have a number of vintage cars on our lot as well as modern vehicles. Many have been modified and have thumpers that actually hurt our ears from the sounds. Wouldn't that be exactly what they deserve? The guys will be happy to hear that you had some in your shop.