I’ve read several threads here lately about wiring and electric fuel pumps. But no one mentions running the circuit threw a safety switch in case of an accident. Is that a thing of the past? I know on a lot of roundy-round tracks, electric fuel pumps are not allowed for safety reasons. Any thoughts on this? Bones
I'd use a safety switch if I were using an electric fuel pump for sure. Easy enough to get one, they're in every late EFI car....
You mean like a late model car's fuel pump inertia switch to shut off the pump after a rear end crash, or say an oil pressure switch to shut the pump off if the engine dies? -Dave
Either one or both, also they have one that shuts off if you turn over. I just never see them mentioned in any of the wiring threads. Bones
My switch fits to a T at the engine adjacent to my oil pressure switch. If in the event of accident there is no oil pressure, the fuel pump automatically shuts down. Apart from being mandatory here on our cars, safety first and keep it simple! My new car has an inertia switch.
They have been talked about plenty on the Hamb, that I know. Specifically in wiring threads ?? When ever we talk intelligently about safety devices you'll get two talking points. One is everyone needs bubble wrap your self and buy a Volvo or any safety feature no matter what is for pussies. Fuel pump cut off is a great one to use
https://www.jalopyjournal.com/forum/threads/pump-off-key.1104979/ for a start, quick search of just the stuff I wrote about using this switch found several other older threads too.
I've been using the impact safety shutoffs in my Studes for a good while. (ford Escort?) they sound like they use a metal ball or plunger inside to trip it. I still haven't found the right Studebaker seat belt buzzer to install, so I haven't installed one of those yet. I'm beginning to lose hope of finding an original one. WHY BE ORDINARY ?
My cars with electric fuel pumps all have inertia switches wired in. I accidentally cut one in half once when replacing a quarter panel on a mustang. It has a ball bearing about 1/2” in a spring loaded cup that moves of you get hit. Make sure or mount it with the red button pointed up. My dad mounted his sideways and when he went over the train tracks it wound trip and shut off his fuel pump. Sent from my iPhone using Tapatalk
Pick a Part is your friend .....Look in the trunk of any Crown Vic or Merc Gran Marquis ....On the left ,(driver), side at the top back corner of the rear wheelhouse ....Two screws..Grab the wire connector & about 6" of the wiring & you are golden ....If you're REAL good, you can peel of & re-use the little fuel shut-off sticker ......
This is common on race cars because of manual transmissions [in 90% of accidents the engine stops dead] Wire the fuel pump via a relay triggered by the oil pressure switch/light Usually they need a button to bypass the oil pressure switch to start the engine ,or you run a wire from the starter solenoid/key/or starter button
When the SHTF and everything goes wrong THEEEE VERY LAST THING YOU WANT for you or your passengers is a fuelpump running AND spraying gas on what ever it wants.
I think most of us are concerned about being pinned in the car after a wreck and having the fuel pump keep fueling a fire. Also the concern would be about the other people in the other car. .
Never read of this topic before. I have a toggle switch on dash for my electric pump but the reasoning had nothing to do with sudden impact. Good idea.
I just wired up an off topic car (rodded Triumph Spitfire) used the Ford inertia switch, then found it also has a cut-out if the key is on and the cam isn't turning. I feel like I'm wearing 2 rubbers!
Adding a no oil pressure switch to the fuel pump circuit: You can use a street elbow with a street tee to install an extra switch using the original sender port on the cylinder block, but a better way to do it is to replace the original sender with a switch that has three prongs, one operating the idiot light and the other two switching the fuel pump. A good part to use is Wells PS 118 as it has the correct threads (1/4 NPT) and pressure switching. On my Ford the stock sender has a 10-32 screw thread on it, so I adapted this to the 1/4" blade terminal of the Wells piece, and to make a really uptown installation use the Wells 1P1606 (or Standard S956) connector. Wells makes tons of switches with different threads etc., I studied their specifications sheet to get this one for Ford. You should be able to find their info on the 'web if looking for a 1/8NPT or other variation. Edit: My pictures didn't come through, so I recopied them, apologies if they now appear twice.
Kid, I didn’t mean to upset you, it’s just that I was a Figherfighter for 33 1/2 years, I can tell you... you don’t want to check out by fire. To each his own. Bones
The oil pressure switch is a good idea, Quick story, Friend had a Hemi powered hot rod project. He started it up and let it warm up while he went in the house for a piss, The float in one of the carbs sank and the engine flooded and stalled, then the electric fuel pump continued to pump gas in to the engine. When friend came back he hit the key with a cylinder full of gas. The engine had been way over bored and he blew a hole in a thin spot in one cylinder. Later he pulled the plugs and cranked it over to clear the cylinders and the coil arced and set the car on fire. Oil pressure switch would have prevented all that. Sent from my iPhone using Tapatalk
I'm surprised (maybe I shouldn't be) that so many of you have thought about this. The roadster I'm collecting parts for will probably use a mechanical pump, but that part of the puzzle hasn't been thought about much. I bristle at the thought of late model technology on a traditional car..., but sometimes it makes sense. Good thread everybody! -Dave
I also prefer mechanical pumps, as I consider them superior for feeding carburetors. But I thought I'd add my two cents about the Wells pressure switches, as they at least look old style. There are sometimes valid reasons for using electric pumps. My investigation into the oil pressure switch was in designing a water injection system. These also need a switch to keep the pump from running when the engine stalls.
No no no , he's in a roadster so none of that matters. His head is pinned between the ground and the deck lid, he got ejected and ran over or decapitaed by the windshield. Anyway you look at this He's dead already and gas is of no consequence.
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