- How to find the right replacement alternator -
1. Robust construction
Marine alternators are usually operated under high loads. To achieve a long service life, they should be equipped with high-temperature grease, large cooling vents, large fans, high strength bearings and high-current diodes.
2. High performance
The alternator output should be between 25% - 40% of your total battery capacity.
3. Structural shape
Most replacement alternators are available in 4 different designs. The structural shape is determined by the width (B), number and spacing (C) of the attachment points (eyes). This can be compensated for with spacers.
4. Belt pulleys
Heavy-duty alternators require different belt widths according to their power. Up to 70A, a 3/8" (10mm) belt is required and up to 100A, a 1/2" (13mm) belt is required. For units above 100A, a double belt is recommended.
Mariusz W. on 24.07.2026
Simply five-star service.
Alessandro F. on 24.07.2026
Everything went smooth. Thanks
Product news, offers & new guide videos. Stay up to date!
New: Get news from SVB straight to your phone!