Heavy Duty Alternator

Why you shouldn't remove the IMS

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.

Replacing a Starter with an Offset Pinion

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.

Mounting Holes on Newer All-Makes Starters

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.

Dual Input IMS Starter

If you service newer trucks, you may have come across ones equipped with a dual input IMS starter. It is important to be aware of it so you can understand how it’s different so you can service it correctly. The dual input IMS starter has two wiring connection inputs, rather than one. These inputs provide both power (+12V) and ground. Together, they give the vehicle control over the power flowing in and out of the IMS when it is energized. This Tech Tip video reviews the differences between a dual input and single input IMS starter.

Troubleshooting Starter Cranking Problems

When there are starter issues, you may think about doing a current draw test to pinpoint the issue. Yet, on a class 8 truck, a current draw test may not reveal what you need to know to fix your cranking problem. Plus, on these vehicles, a current draw test is more involved and time-intensive. And perhaps most frustrating—you often don’t get an accurate reading. That’s why the BorgWarner technical team recommends another diagnostic route to identify the issue and fix the cranking problem.

Working with Electric Motors

Electric drive vehicles have high voltage electrical systems not found on typical vehicles powered only by gasoline or diesel engines. Because of this, it’s important to be aware of high voltage hazards before you inspect an electric motor. Specifically, be aware of the high voltage interlock switch. In this Tech Tip video, we provide a brief explanation of the high voltage interlock switch and explain how it works.

Measuring Alternator Current Draw

Measuring the current draw is the best way to ensure the alternator has sufficient output for all of the vehicle’s electrical demands. This video walks you through the steps to measure the current draw for a school bus.

Converting an on/off fan drive to a DuroSpeed™ Fan Drive

The DuroSpeed™ K32 Fan Drive is becoming the go-to fan drive for vocational and off-highway truck applications. Designed for harsh vocational applications, DuroSpeed provides reliable performance by having a higher disengaged speed to satisfy cooling demands. In this Tech Tip video, we explain how you can easily convert any BorgWarner K30 or K32 on/off fan drive to a DuroSpeed fan Drive.

Benefits of Oversizing an Alternator

When managing a fleet, the goal is always to get the most out of your equipment. We’ve got an innovative way for you to do just that: oversizing the alternator. Oversizing an alternator is a proven strategy that benefits you in three ways: 1. Fuel Savings 2. Longer Alternator Life 3. Better Battery life In this Tech Tip video, we explore these benefits.