Introduction: Failed Car Alternator Work Around

About: There are some things you should just NEVER do.....

Failed Car Alternator Quick Work Around

So you car's alternator has failed and you have no time to get it fixed... Your battery under the hood may even be dead from running your car without a functioning alternator. You need to drive your car NOW!.... What to do?

My solution was to add a second battery in the passenger compartment that could be easily charged or swapped out to keep the car going and get you to your destination. You don't have to wait to charge the dead battery and you don't have to swap out the battery under the hood.

Add a second battery on the passenger floorboard. You get twice the capacity with both batteries charged. Remember your car electrical system is running only on battery and is not being recharged by the alternator -- ultimately the batter(ies) will be exhausted and your car will not drive, so having more battery capacity is a good thing.

This quick 'fix' gets you up and driving as fast as possible with minimal work on the car.

CAUTION / DISCLAIMER: Although I have used the method described to drive a car with a broken alternator, I do not recommend it. This Instructable is mainly for entertainment purposes. There are many hazards that can be introduced and many that may be unforeseen. So don't do it. If you do, you are responsible for your actions and not me. In other words, I don't want to hear from your lawyer! Be safe and smart.

Step 1: Materials


1. Second Automotive Battery (Fully Charged - You keep it charged all the time just in case, don't you?)

2. Long Heavy Duty Jumper Cables

3. The All Important Duct Tape

Step 2: Position Your 'Secondary' Battery on the Passenger Floorboard

Place the second battery on the passenger floorboard, making sure it is level and stable. You don't want it falling over and spilling electrolyte (sulfuric acid).

Step 3: Run the Jumper Cables Through the Window

Open the passenger's window and run the jumper cables through the window.

Make sure the jumper cables are not shorted together. You can do this by clamping one of the jaws onto the insulated cable so they don't touch. Only do this if the teeth on the jaw will not damage the insulation on the cables.

Step 4: Open the Hood and Run the Jumper Cables to the Battery

Snake your jumper cables across the engine compartment to the existing car battery. Make sure that the jumper cables will not get caught in any moving parts, especially belts or fans. Make sure the cable insulation will not contact hot parts and melt. Make sure the cables will not bounce around and get caught in moving parts or contact hot parts. You might have to use some duct tape here.

Step 5: Connect the Jumper Cables to the Car Battery

Connect the jumper cables coming from the passenger compartment battery (not connected) to the car's battery under the hood. Position the jumper cable clamps/jaws to that they can lay as flat as possible so that the hood could be closed. Make sure that the clamps don't short against each other or the opposite battery post or to the car frame or other metal.

Step 6: Gently Close the Car Hood Until the Safety Catch Engages

With the jumper cables positioned as near to the front of the hood as possible, gently close the car hood making sure that nothing shorts out and nothing gets pinched. You won't be able to close the hood all the way because of the jumper cables leaving the engine compartment. But gently close the hood until the Hood Safely Catch Latches onto the hood.

Reposition the jumper cables if necessary to get the hood to close enough to engage the Safety Catch. This catch keeps the hood from flying off in case it was not closed properly or the main latch fails. In this case the Hood Safety Catch keeps the hood closed while driving.

If you're Hood Safety Catch is not there, is damaged, or doesn't function properly don't use this Instructable.

Step 7: Tape Down the Jumper Cables

Duct Tape the Jumper Cables in place from the engine compartment back the the passenger compartment.

Carefully roll up the passenger window so that the window is as closed as it can be without pinching the jumper cables too much.

Step 8: Connect the Interior Battery

Connect the Jumper Cables to the passenger compartment battery.

Your are good to drive off to your destination!


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