12V Alternator Kit for Sprinters
12V Alternator Kit for Sprinters
Here's a great RoamRig Guide to Regulator & Alternator Charging.
If you are building a van with a large lithium battery bank, a second alternator is KEY to realizing the full capabilities of that bank. Imagine having an electric car with a 1000 mile range when it is charged, but charging it takes 2 days of being plugged in? That is what it is like when you have a large lithium bank without a second alternator. A second alternator will help you realize the full capacity of your battery bank. Full product description below.
Each kit features a Balmar brand 250XT alternator. RoamRig has used literally hundreds of these in the field with no known alternator failures. Each alternator is equipped with a custom Litens pulley that is unique to RoamRig kits and not available on ANY other alternator from any manufacturer. This pulley ensures that the belt drive will remain stable and quiet across all operating conditions, and also that you will have a long life of the entire belt drive. It is critical for all Sprinter alternators to use a Litens brand OAD pulley, and NOT any other style of clutch pulley or you risk having belt drive stability issues that cause noise, may damage components, and can leave you stranded.
Note: if you have a 4cyl engine on the new 2023+ Sprinter, the kit will come with a bracket regardless of whether you have N62 or not so that a tensioner can be used instead of the risky stretch belt that Mercedes specs for N62 OM654 engines. Please email us for more info if you would like more details.
See the Installation Instructions.
RoamRig's second alternator kits feature Balmar alternators with Balmar regulators. Balmar regulators are simple, proven, robust, and very configurable. We include custom bespoke harnesses that connect the alternator harness to a vehicle harness which will then connect to power and engine run signals under your driver seat. All you have to do is connect this to a fused 12v source on your battery bank for voltage sensing and to your battery bank ground. Our harness sets use Deutsch connectors and other weather tight automotive connectors at the alternator itself.
All RoamRig alternators come with a very important custom Litens pulley. This pulley is not available anywhere else. It ensures long life of all belt drive components (belt, tensioner, etc) and ensures that there will be no adverse noises or NVH concerns from unstable belt drive behavior that happens with other pulleys used by other alternator kit manufacturers.
Balmar alternators produce well over 100A at idle with an appropriately sized battery bank and 250A at cruise speed. The competition claims their alternator produces 280A at cruise speed, but their alternator is just a rebranded 220A GM alternator that only produces 280A when cold and quickly loses output when warm due to increased internal resistance and other inefficiencies. Please see the data sheet below for test data.
If you purchase a bracket set, it will be a Techni brand bracket that closely emulates a Mercedes N62 option bracket. If your Sprinter came with an N62 bracket, this alternator will bolt right in.
• 1x Balmar alternator (250A for 12V systems)
• 1x Balmar APM12 alternator surge protector
• 1x Custom Litens Pulley (installed on alternator)
• 1x Balmar MC-618 regulator, regulator bracket, and Sprinter specific harness set (if kit is configured with regulator)
• 1x Techni brand bracket set (where applicable)
• Installation instructions