OEX Alternator 12V 80A Hitachi Style HXA9404

The OEX Alternator HXA9404 is a 12V, 80A unit in Hitachi style, built as a new alternator with an internal regulator and twin leg mount. It is listed with a 74mm pulley outside diameter, 82mm inside mounting legs, a 175mm centre-to-centre mount, and an M8x1.25 adjusting hole.

This alternator is identified as suit Yanmar Marine, with an insulated return and a specific installation note: battery negative must be attached to either of the two M5 insulated studs near the mounting foot. That detail matters on marine applications where the return path and mounting arrangement need to match the equipment exactly.

OEX is sourced from market leading original equipment manufacturers and aftermarket suppliers, with products sourced from ISO certified factories and backed by a one year warranty. For buyers comparing replacement units, the key identifiers here are part number HXA9404, 12V system voltage, 80A output, CW rotation, and Hitachi suit make.

Key Features

• 12V alternator with 80A output
• Hitachi style unit
• Part number HXA9404
• New unit with internal regulator
• Twin leg alternator mount
• Insulated return design

Specifications

• Brand: OEX
• Product type: Alternator
• Part No.: HXA9404
• Voltage: 12V
• Power rating: 80A
• Regulator type: Internal
• Suits unit make: Hitachi
• Rotation: CW

Application and Buying Notes

Before ordering, check the part number HXA9404 against the existing alternator or the machine documentation. This unit is described as a Hitachi style alternator and is listed to suit Yanmar Marine, so the most reliable match is one that agrees on voltage, output, mount layout, pulley size, and regulator arrangement as well as the part number.

The mounting dimensions are important on this unit: 82mm inside mounting legs, 175mm centre-to-centre mount, 10mm pivot hole diameter, and M8x1.25 adjusting hole diameter. If any of those points differ from the unit being replaced, fitment should be rechecked before purchase rather than assumed from appearance alone.

Electrical connection details also matter here. This alternator has an insulated return and the note specifies that battery negative must be attached to either of the two M5 insulated studs near the mounting foot. That is a practical installation checkpoint, especially on marine equipment where the return path must be connected correctly.

The pulley and rotation details should be confirmed as well. This unit is specified with a 74mm pulley outside diameter, A section pulley, and clockwise rotation. Those details can affect belt alignment and whether the replacement is a direct swap or only a close visual match.

If you are replacing a marine alternator, compare the complete assembly rather than only the mounting ears. Voltage, amperage, rotation, pulley section, regulator type, and the insulated return arrangement all need to be checked together. That approach reduces the chance of ordering a unit that looks similar but does not connect or operate the same way.

Before supply, the safest approach is to confirm the original unit details against the listed part number, voltage, output rating, mounting arrangement, and pulley configuration. That checking process is standard practice in the parts trade because visually similar units can still differ in service-critical ways.

For workshop, fleet, and equipment applications, accurate identification of part number HXA9404 helps avoid unnecessary freight, additional labour, and vehicle or machine downtime. Where the application is not straightforward, the original unit, OEM reference, or workshop records should be used as the primary confirmation point.

Relevant published details for this unit include Type ALTERNATOR, Unit of Measure EACH, Warranty One Year, Inside Mounting Legs 82mm, Pivot Hole Diameter 10, Pulley Outside Diameter 74mm, Regulator Type Internal, Suits Unit Make Hitachi, Note To suit Yanmar Marine. Must attach battery negative to either of the two M5 insulated studs near mounting foot., Mount Cnt to Cnt 175mm.

Additional published details for cross-checking include Insulated Return Yes, Product Group 2 ALTERNATORS, Part No. HXA9404, Brand OEX, Description OEX Alternator 12V 80A Hitachi Style, Adjusting Hole Diameter M8x1.25, Pin Code IR15, Power Rating (Amp) 80, Pulley Section A.

OEX Alternator 12V 80A Hitachi Style. Part number HXA9404 should be checked first. Listed voltage is 12. Listed output rating is 80. These details form the core reference points used by parts interpreters when confirming the correct replacement.

Mount style is Twin Leg. Regulator type is Internal. Pulley configuration is A. Those physical and electrical details should line up with the original unit before the replacement is approved for fitment.

For part number HXA9404, the normal identification sequence is part number, electrical rating, mounting arrangement, connector or terminal style, and pulley or drive details. Using those checkpoints helps confirm that the listed unit matches the service requirement rather than only looking similar.

For a alternator in workshop, fleet, trade, agricultural, or construction service, the listed voltage 12 and output 80 should be checked carefully. Incorrect selection can affect installation time, return freight, and equipment availability.

Where no verified application list is available, the part number, mounting details, connector style, and published specifications should be used as the primary selection criteria.

In the absence of a verified fitment list, the safest approach is to compare the removed unit directly with the listed product details. That includes checking the housing style, pulley layout, regulator arrangement, and any visible identification numbers before supply is approved.

The listed warranty is One Year. Warranty terms should be considered alongside correct application and part identification, as warranty does not replace fitment confirmation.

Compatibility note: Confirm fitment using part number HXA9404, the Hitachi style application, and the listed mounting and electrical details before ordering.

FAQ

What is the part number for this alternator?

The part number is HXA9404.

What voltage and output does this alternator have?

It is a 12V alternator with an 80A power rating.

What type of regulator does it use?

It uses an internal regulator.

Is this a new or remanufactured unit?

It is listed as a new alternator.

What application is noted for this alternator?

It is noted to suit Yanmar Marine.

What should be checked during installation?

The note specifies that battery negative must be attached to either of the two M5 insulated studs near the mounting foot, and the unit should be checked for the listed mounting and pulley dimensions before fitting.