Gm Hei Distributor Wiring: Simplified Schematic

The GM HEI distributor system is an integral part of many General Motors vehicles. It is a reliable ignition system that has stood the test of time and is still used in many vehicles today. The distributor is responsible for providing spark to the engine at the correct timing, enabling it to perform its best.

A distributor in a GM HEI system is essentially a device that takes a signal from the ignition coil and sends it to the spark plugs at the right time. This is done by way of a rotating armature, which is connected to the camshaft. As the camshaft spins, the armature spins as well. This causes the contacts inside the distributor to switch on and off, thus providing spark at the proper time.

The main components of a GM HEI distributor are the body, rotor, cap, pickup coil, ignition module, and ignition coil. The body acts as the mounting point for the other components. The rotor sits on top of the shaft and is what the spark plug wires connect to. The cap covers the rotor and protects it from dust and dirt. The pickup coil senses the position of the rotor and sends a signal to the ignition module. The ignition module then sends the signal to the ignition coil, which creates the spark that is sent to the spark plugs.

Wiring a GM HEI distributor is relatively straightforward. First, the positive terminal of the battery must be connected to the positive terminal on the ignition module. Then, the negative terminal of the battery must be connected to ground. Next, the spark plug wires must be connected to the cap in the correct order. Finally, the power and ground connections on the ignition module should be connected to the corresponding terminals on the coil.

The firing order for a GM HEI distributor is 1-8-4-3-6-5-7-2. This means that the spark plugs in the engine should fire in this order. The number one cylinder should fire first, followed by the second, third, fourth, fifth, sixth, seventh, and finally the eighth.

When it comes to setting the ignition timing for a GM HEI distributor, there are two methods that can be used. The first method is called “static timing” and requires the use of a timing light. This method involves setting the distributor to the desired timing mark and then using a timing light to adjust the timing until it is correct. The second method is called “dynamic timing” and requires the use of a vacuum gauge. This method involves connecting the vacuum gauge to the distributor and then adjusting the timing until it is correct.

Common problems with GM HEI distributors include misfiring, rough idle, poor fuel economy, and failure to start. If your vehicle is experiencing any of these symptoms, the distributor should be checked for any signs of wear or damage. In most cases, replacing the distributor will resolve the problem.

If your GM HEI distributor is having issues, the first step is to troubleshoot the system. Begin by checking all the connections to make sure they are secure. Then check the spark plug wires to make sure they are all connected properly. Finally, check the distributor cap and rotor for any signs of wear or damage. If any issues are found, they should be addressed before further troubleshooting is done.

If you are looking to upgrade your old points distributor to a GM HEI system, the process is relatively simple. Begin by disconnecting all the wiring from the points distributor and remove it from the engine. Once this is done, the GM HEI distributor can be installed using the included instructions. Make sure all the wiring is connected correctly and the distributor is set to the proper timing. Once this is done, the engine can be started and the system should be working properly.

The GM HEI distributor system is a reliable and long-lasting ignition system. It is important to understand how it works and how to properly maintain it. Knowing what each component does, how to wire a GM HEI distributor, and how to set the ignition timing can help ensure your vehicle runs smoothly and reliably.