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Welding Off Car Battery. Here is what I have read lately about welding on vehicles. Sure you can weld by using your car battery.
Modern vehicles use a control circuit which regulates the voltage in and out of the alternator to prevent over charging. Welding the body is the same it is often isolated from the frame and engine. At the same time having too much power can force your hand in the opposite direction.
The exhaust is on rubber isolator mounts and has a rusty connection to the engine.
Your welds will melt too far and youll have an entirely new problem on your hands. The battery of the car should be divided on the negative side. I hear about welding with car batteries but can you weld off your running vehicle. Your welds will melt too far and youll have an entirely new problem on your hands.