So does your application require a ballast resistor? Quite simply, if your distributor has breaker points the answer is yes; if not, the answer is no. See all 7 photos 2 Older points-style ignition system used a single resistor which reduced amperage to the coil resulting in extended life for the coil and points.

Why is a ballast resistor needed?

A ballast resistor is used in a device to compensate for changes and secure the other components of a network. When the current flowing through the resistor increase, the temperature also increases. And due to the temperature rise, the resistance also increases.

What does a resistor do in an ignition system?

The ballast resistor allows the ignition system to operate at a lower voltage until the engine starts. After ignition, the alternator begins to recharge the battery, restoring the regular voltage.

How do you tell if a coil needs a resistor?

To test your ballast resistor you need an ohm meter or multimeter set to ohms. Remove the connectors from both sides of the resistor. The ohms should read between 1.8 and 5 ohms. You should be getting 9 volts to the positive side of the coil.

Does a ballast resistor reduce voltage?

The ballast resistor, supplies the needed voltage during the start up, and then immediately after the arc is established, it reduces the voltage in addition to regulating the current flow.

What will a bad ballast resistor do?

If your ballast resistor is bad, your vehicle will not run and you will have to have it towed to the mechanic’s shop. … The biggest sign your ballast resistor is bad is your vehicle will start, but immediately stop as soon as you let go of the key.

Can you bypass a ballast resistor?

The duty of the ballast resistor is to limit voltage to the ignition coil. … A quick and easy way to diagnose ballast resistor failure is to bypass it by running a temporary jumper wire from the battery to the coil. If it starts and remains running, you’ve found the problem.

How do you know if a ballast resistor is bad?

Measure the voltage (or check with a test light) the voltage between the single wire and ground. If there is power there, the ballast resistor is likely bad. Reconnect the wires and measure the voltage at the positive side of the coil. If you see 8-13 volts, you may have a bad coil.

Do I need a ballast resistor with MSD ignition?

Late-model electronic ignitions or an MSD Ignition do not require the ballast. If you are looking to upgrade your stock coil, or want to compliment the performance of your MSD Blaster Ignition, MSD 5, 6, or 7, the Blaster Coil line is the right choice. Our Blaster Coils are designed for improved spark output!

Does HEI distributor need ballast resistor?

When using HEI, the distributor requires a 12 volt feed. In order to achieve this the ballast resistor or the resistance wire must be removed from the circuit and replaced with a pure 12 gauge feed wire. … This means that there is no power on the “RUN” circuit when the ignition switch is in the “CRANK” mode.

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What's the difference between a ballast and non ballast coil?

A ballast coil is designed to produce the same spark output, but with only 6 to 9 volts on the input. With a non-ballast coil, the input to the coil is the same, 12 volts, whether the engine is running, or being cranked by the starter motor.

How do you wire a ballast resistor?

1. Step 1: Determine if Ballast Resistor Is Needed. …
2. Step 2: Locate Ballast Resistor along Firewall. …
3. Step 3: Drill Holes for Securing Resistor. …
4. Step 4: Install Ballast Resistor. …
5. Step 5: Connect Wires to Positive.

How many ohms should a 12 volt coil have?

You should have a resistance reading of at least 3-4.5 ohms. A bad coil will show a higher reading then 3-4.5. Next, place the red or black lead from the meter to the centre of the coil , and to either one of the terminals positive or negative. You want 9500-10000 Ohms, a little less is ok but no more.

Does a ballast resistor have polarity?

Resistors are not like diodes or capacitors. They do not have a polarity. The conduct (or resist) current equally in both directions of current flow. In manufacturing, you will often see resistors all installed in the same direction.

Can you hook up a ballast resistor backwards?

Resistors lack polarity. There is no backwards.

What effect does the open circuit have in the primary circuit on the ignition system?

When the points open and close it triggers the primary ignition circuit, which in turn fires the coil. Inside the distributor, there is something called the rotor which rotates and deliver the spark to the correct spark plug wire which ignites the spark plug.

Can you test a ballast with a multimeter?

Test your electronic ballast’s resistance using your digital multimeter. To measure it, set your digital multimeter to around a thousand ohms resistance setting. Connect the black leads to the white ground wire on your ballast. … When you do this test, a good ballast will return an “open-loop” or max resistance.

What Ohm ignition coil should I use?

The 3.0-ohm coil should be used on PerTronix Ignitors installed on four- and six-cylinder engines while 1.5-ohm coils should be used for eight-cylinder applications. … Flame Thrower II coils have lower resistance, 0.6 ohms for use with Ignitor II ignition systems as well as many other high-energy ignitions.

Does a Blaster 2 coil need a ballast resistor?

blaster two Yes, you must have a ballast resistor.

Does MSD coil increase horsepower?

No, unless they’re somehow defective as installed. If you’re asking if aftermarket coils installed in a stock engine will increase horsepower, or reduce emissions, or increase gas mileage, or make the engine run smoother, the answer is no.

What is a ballast resistor for a ignition coil?

A Ballast Resistor is an electrical device that reduces voltage to the coil so that more energy is available for the spark plugs during starting.

Do I need a coil with HEI distributor?

Most—but not all—HEI systems have the ignition coil mounted in the distributor cap. A control module and magnetic pickup are mounted in the distributor, in place of a conventional ignition system’s breaker points and condenser.

How many amps does a HEI distributor draw?

Actually, an HEI draws only 2- to 3-amps, compared to the approximate 6-amps an external oil-filled coil draws. The lower amperage draw results in a much cooler running HEI coil.

How do you tell if you have points or electronic ignition?

It’s fairly simple. If you open your hood, be sure your car has a distributor cap with very thick wires coming out of the top and going to each spark plug. If you don’t have a standard distributor cap like this, you don’t have points. If you do have a standard distributor cap, you can open the cap up and peek inside.

Will any ignition coil work?

Currently most all automotive ignition coils are application-specific and are not interchangeable from one manufacturer to another. If you are asking about a different type or use of an ignition coil then repost the question with the specifics.

How do you check a ballast coil?

To find out for sure, use a multimeter to check the voltage on the positive wire of the coil with the ignition on. Around 9v means you have a ballast, around 12v means you don’t.

What does ballast ignition mean?

The later ballasted ignition system used a modified coil that delivered a full power spark which was reduced by installing a ballast resistor or resistor wire in the power feed to the coil.

Does a ignition coil have to be grounded?

Dear Jackie, Let me disagree with other answers: An Ignition Coil does not need to connect to ground. It needs to be capable of receiving electrical pulses on its input. It is , after all, a transformer and the primary winding is pulsed to make a HV spark on the Secondary winding.

How does a ballast limit current?

The ballast adds positive impedance (AC resistance) to the circuit to counteract the negative resistance of the tube, limiting the current.

Should there be voltage on negative side of coil?

If “no HT or distributes connected” means that thevside which is not connected to the positive has no connection on it, and if the coil is not open, the other terminal should have positive 12 volts on it.

What causes a coil not to fire?

There are a few reasons for no spark, new coil pack could be defective, crank sensor, ignition module or bad wire in primary circuit, faulty ECM/PCM. You may have to have a good technician have a look, diagnose and estimate repair.