Heavy Duty Alternator

There are many different alternator mounting positions and belt configurations on heavy duty diesel engines today.

A starter engagement system is responsible for engaging the pinion with the ring gear, keeping the pinion engaged while cranking, and disengaging the pinion after the engine starts. There are three different types of starter engagement systems that can be used in vehicles: positive shift, soft start, and indexing drive. In this tech tip video, we walk through how each works, as well as where it's most likely to be used.

Some of our newer all-makes starter models have larger mounting holes—this makes them more versatile as they are able to fit engines with either size bolt. The mounting holes on newer models are five-eighths of an inch. That’s slightly larger in diameter than the nine-sixteenths of an inch on the older models. That difference, though, doesn’t limit if and where you can use the starter. The solution to accommodate the larger holes is quite simple and inexpensive. All you need are flat washers. We recommend a grade 5 or better washer for each of the mounting holes. This flat washer accommodates the change in bolt hole size without needing anything more.

If you are unfamiliar with the IMS, you may try to remove it—not realizing its many benefits. Many of the Delco Remy brand starters come equipped with an Integrated Magnetic Switch, or IMS. The IMS provides a higher current draw for the motor. It does this by reducing voltage drop and controlling battery current. This ensures the solenoid receives the maximum available voltage in any starting condition. If you are unfamiliar with the IMS, you may try to remove it—not realizing its many benefits. However, doing so would result in significant control circuit problems. It will also void your warranty. If an IMS is part of your gear reduction starter, you should never remove, bypass or uninstall it. This video provides two options for you to consider.

This Tech Tip reviews how the use of Remote Sense can impact diagnosing voltage complaints.

In this Tech Tip Video, we explain why you can replace a starter with an offset pinion with one that is centered. Despite the new starter having a different pinion size, tooth count and placement it may still be able to be used. Starters are designed to match the engine ring gear for proper mesh and performance. Most starters—including Delco Remy branded starters—have a centered pinion. However, some manufacturers use an offset pinion. If the old starter’s pinion is offset and the new one is centered, you will notice the pinion on the new starter is larger in size. The larger pinion is needed in order for the pinion to reach the ring gear when it is centered. Additionally, you’ll likely notice a higher tooth count. An offset pinion, on the other hand, has a smaller pinion size. So, in order for it to reach the ring gear, the pinion is offset and moved closer to the ring gear. Frequently, an offset pinion will have fewer teeth.

In this Tech Tip, we’ll review how starter spacers are utilized as well as how to measure the starter flange to flywheel so that during any maintenance, the starter is properly mounted and performs as designed.

Experiencing problems with your alternator charging system? Squealing noises under the hood. Headlight bulbs that blow out repeatedly or dim. Dash voltmeter gauge out of range—either too high or too low. These are common indicators that something may be wrong with the charging system. If any of these symptoms are evident, then this video is for you. This video will walk you through five steps to pinpoint potential issues.

Have you ever installed an alternator that won't charge? The Flash the Field Tech Tip video will show you how to easily fix this alternator problem. This strategy only applies to the following Delco Remy alternator model families: 20SI, 21SI, 22SI, 23SI, 26SI, 30SI and 36SI.