Connected Battery backwards...ouch!

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wwwfora

wwwfora

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I have a 1973 Dodge Dart Sport. Connected battery backwards, hit the ignition and saw white smoke. I found the wire that burned out, but the fuel pump stopped running, so I bypassed it directly to what looks like a solenoid connected to the engine block at the back of the engine? I'm trying to trace the route of the electric fuel pump wires. What is this, metal thing screwed into the back of the engine block? The care cranks over and fires about 2 cylinders and then just cranks? Any suggestions on what else I could have burned out? Relays, ballast, solenoid, MSD timing? Any help would be great, I feel like a total #$% A$#!
 
the thing screwd in the back of a small block v8 is the oil preshure sending unit. wouldn,t hurt it. your just going to have to look at things one at a time.The electronic things possibly could be damedged but not nesesarily.do you have spark. If not check to make shure the modual has power.If it does and you don,t have spark your in trouble.i douwt you would hurt the fuel pump but if its not pumping folow the power path.check fuseable link.good luck
 
Thanks for the response, I connected the electric pump directly to the battery and started the car, and it runs fine. Idle is a little high. For some reason the pump won't kick on when the key is starting the engine. Either the relay is bad, or the oil pressure switch is bad. Reason I think this, I put a test light on the side of the oil pressure switch when the key was in the on position and it lit up, when you turn the key, the other side of the switch does not light up. This means the current is not being passed through it. hence it could be friend. Strange this guy never put a fuse between the batter and the rest of the circuits. Plain stupid.
 
oil preshure switch word doesn,t make sense to me.The oil preshure sending unit is for the gauge or light only.it has nothing to do with the fuel pump or motor running. it just tells you when you don,t have oil preshure.a good place to power the fuel pump relay if you have one is the dark blue wire that goes to the electric choke and ignition.Do not run the pump directly from it with out a relay in between or run it from a seperat switch.I persanally don,t like ad on electric fuel pumps for moderate hp motors.They don,t no when to stop pumping and are a grate way to burn a car to the ground.
 
Cudaman, I followed the electric pump to the Oil Pressure Safety Switch, this then goes up under the steering column, probably to the Ignition, which runs then to relay and so forth. The sending unit is below the safety switch. It's just a brass fitting with copper tube running inside the firewall to the guage.
I don't have a chock on my Carb, some reason he took it off. This car is setup for drag, and I want to tone it back down. True about the pump, it holds a constand 6 psi to the carb, and when i'm gently accelerating it sputters and spits and bucks like a horse, probably because of the fuel pump. What are my options to take this thing out? And like you said, if something breaks this is going to shoot gas everywhere. Thanks for your ideas.
 
The dark blue wire that comes from the ignition switch runs the ignition ,choke and alternator field is the one to triger the fuel pump relay.It sounds like you had a safety feature on your fuel pump. I am not familiar with it.Maybe some one else has one and noes more about it.That blue wire will turn the pump on
 
Thought from the cheap seats: Dad always told me that hooking up your battery backwards could reverse the polarity in your alternator too. Good luck!
 
well i had a little time to think about what you could have.One way to make an electric fuel pump safer is put in a timed relay with a preshure switch.the relay would have NCTO on it.normal closed timed open.the presher switch would be N.O. normal open hooked across the normal closed contact on the timed relay.the relay would be closed when you first put the key on and then time open. by then the moter should be running and the presher switch would be closed maintaining power on the fuel pump as long as motor is runing maintaining oil preshure.Thats one way to do it.Thats the same concept thats used in modern cars.My circiut is just a little on the primitive side.I hope i didn.t confuse you but its posible thats what you have and when you reversed the polarity you damaged the timer. Hi cuda chick.That reverse thing is a caryover from the old days with generators. It would not apply to alternators for they generate ac and then use bridge rectifiers to change it to dc.have a nice day everybody.
 
Just a thought. The pump relay may have a reverse diode in it that got fried from the battery being hooked up backwards. Some relays have a diode to prevent back current when the power is removed since the coil will have a kick to it when the power is cut. The collapsing electric field generates a reverse current from the relay coil and the diode stops that. If you fried the diode, you may have an open circuit in the relay and it won't close.
 
Thanks Cudaman! I guess that's just showin my age now huh??? Ah, well ... any excuse to think about dad is a good one.
 
I bet you hit the nail on the head dartnewbie that makes sense. I no what you meen cuda chick. My dad just went from the hospital to the nerseing home with alzheimers and it,s tuff.
 
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