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  • *SALE* 80A Yanmar Marine Alternator - Externally Regulated

    $346.00 $329.99


    I Do Not Ship Alternators Internationally


    IMPORTANT:  All CMI Alternators are hand built and may require a 3-4 week lead time.

    The CMI-80-ER: 

    This is the first and only Hitachi/Yanmar case alternator I know of that is available & set up for external regulation. I started with the finest aftermarket parts I could source & then built this from the ground up as a better alternative to the stock Yanmar/Hitachi alternators. You will not find a better price on a Yanmar specific externally regulated entry level alternator.

    External Regulator: 
    If you select the drop down menu you will see that I can package this alternator with either a Balmar MC-614H or ARS-5H regulator. I recommend setting the Belt Manager feature to level three or four when setting up the regulator. It is also mandatory that an alternator temp sensor be used. I only recommend using Balmar regulators with this alternator.

    Core Charge: 
    I will refund a core charge of $35.00 for a returned working Hitachi 80A alternator.

    CMI-80-ER Specifications:

    This is not a cheaply built re-badged automotive alternator with a dumb internal regulator. This is an Yanmar fit, dual foot, externally regulated 80A alternator intended to replace the Yanmar / Hitachi LR180 series, and other Hitachi's, found on many small Yanmar engines.

    I worked with my manufacturer for many months to source the right parts, test it, and ensure it could perform at the price point I desired. Some of the components we tested for this alternator failed in less than an hour at full output.

    This Hitachi cased alternator is hand assembled in the USA to Compass Marine's stringent specifications. This ensures a quality product at a fair price. Some of the components are made overseas but we sourced the best components we could possibly find, and we tested them, to meet the value to performance ratio I was looking for.

    This alternator fills the gap between a true high performance alternator (see my other alternator offerings) and the factory alternator. It was designed to meet a price and performance niche not available to boaters previously. This is a what I consider a medium/light duty alternator intended for smaller banks that just need healthier charging profile. It is not intended to drive large AGM banks, large flooded banks or large GEL banks. See my other alternator offerings for this type of use.


    The CMI-80-ER comes standard with a tachometer output wire (stator tap) for Yanmar diesels that run the tachometer sense off the alternator. Not all Yanmar engines drive the tachometer from the alternator, but some do. The CMI-80-ER is set up for external regulation only. It has no internal regulator. The vertical plug of the "T" connection is the FIELD terminal to be driven by an external regulator. The cross of the "T" plug is not used.

    Special features:

    • Intended to fit to the Yanmar engines that use a 3.15" saddle mount alternator.
    • 80A cold rated, with good high idle performance.
    • Machine wound stator of 14GA top quality magnet wire means better cooling and higher temperature tolerance.
    • Precision machined rotor and slip rings for greater contact at all RPM.
    • Tighter tolerance of stator/rotor gap for better performance. The specs are better than the very expensive Hitachi branded alternators..
    • Rotor is precision balanced to .035 ounce inches. Industry norm is .050 - .090. This means smoother operation and less harmonics.
    • Upgraded higher performance diode rack.
    • Brushes are high copper content not run of the mill carbon brushes. This yields superior conductivity and considerably longer brush life.
    • Ready to accept an external regulator (I recommend only Balmar regulators).
    • 1/2" / 13mm single v-pulley (3/8" / 10mm available upon request).
    • Billet machined pulley not cheap stamped steel.
    • Isolated ground for steel or aluminum boats or for using a shunt in the negative path..
    • Hand assembled in the USA (Note: some internal components are non US made but carefully chosen)