Alternator for Mercruiser 400-12408

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Overview

DB Electrical Alternators
DB Electrical keeps watercrafts moving forward with quality aftermarket alternators. We work directly with factories to ensure each component is manufactured to our exacting quality control standards. But because there is no middleman, we can offer these exceptional-quality electrical components at low factory direct prices.

With DB Electrical alternators, you’ll get …

Superior Quality Every Time – Our aftermarket alternators deliver performance that’s equivalent to the original.
Direct-Fit OEM Replacement Parts – DB Electrical aftermarket alternators are designed for perfect fitment to replace the ones that originally came with your vehicle.
Engineer-Tested Excellence – Our alternators go through a rigorous testing program to ensure optimal performance. Most alternators are supplied with their final test results and performance curve.

Reasons to choose DB Electrical for your next alternator:

Built to Take the Heat – Most DB Electrical alternators offer high-temperature epoxy, heavy-duty rectifiers, high-quality regulators, top-quality bearings and high-temperature grease for better charging and longer life under high-heat environments.
Corrosion Resistance – Plated fans, pulleys and hardware offer protection against rust-producing dampness.
Flame Arrestor Screens – Where applicable, alternators come with these screens to meet Marine SAEJ1171 Certification as laid out by the SAE.
Brand New Alternator – Never settle for a secondhand one. Many places will try to sell you a used alternator for about the price we’ll sell you a new one.

The DB Electrical Advantage – 1-Year Warranty
DB Electrical delivers exceptional value for products that we stand behind with our total-confidence 1-year warranty. Yes, you have a full year to make sure your alternator meets your expectations.

Item Number: 400-12408

100% Brand New Aftermarket Part From DB Electrical

Product Specs

Item Condition	Aftermarket Part
Part Type	UNIT
Voltage	12
Rotation	CW
Amperage	105
Clock	12
Pulley Class	S6
Regulator	IR
Fan Type	IF
Fits	MARINE APPLICATIONS 6-GROOVE PULLEY 50mm OD
Critical Note	Any High Amp Upgrade Needs to Be Professionally Installed

Applications List

Select Make & Type

MAKE	TYPE	MODEL	YEAR	ENGINE
Mercruiser	Engine	Black Scorpion Ski (Gen +)	1997	350cu in 5.7L 8 cyl
Mercruiser	Engine	Model 350 Mag MPI (Gen +)	1999	5.7L 8 cyl
Mercruiser	Marine	Model 350 Mag MPI Alpha & Bravo	1998	5700cc 5.7L 8 cyl
Mercruiser	Marine	Model 350 Mag MPI Alpha & Bravo	2001	5700cc 5.7L 8 cyl
Mercruiser	Marine	Model 350 Mag MPI Hor Alpha & Bravo	2001	5700cc 5.7L 8 cyl
Mercruiser	Engine	Model 350 Mag MPI Horizon	1999	5.7L 8 cyl
Mercruiser	Engine	Model 350 Mag MPI Ski (Gen +)	1998	5.7L 8 cyl
Mercruiser	Marine	Model 4.3L (Carb.) Alpha & Bravo	2002	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L (Gen +)	1998	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L (MFI) Alpha & Bravo	2002	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L EFI	1999	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L EFI (Gen +) TBI	1998	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L EFI (Gen +) TBI	1999	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L EFI (Gen +) TBI	2000	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L EFI (Gen +) TBI	2001	4300cc 4.3L 6 cyl
Mercruiser	Marine Stern Drive	Model 4.3L MPI	2001	262cu in 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L MPI	2001	4300cc 4.3L 6 cyl
Mercruiser	Marine Stern Drive	Model 4.3L MPI	2002	262cu in 4.3L 6 cyl
Mercruiser	Marine	Model 4.3L MPI	2002	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 4.3LH (Gen +) (4-BBL)	1998	4300cc 4.3L 6 cyl
Mercruiser	Marine	Model 454 Mag Bravo MPI (Gen VI)	2000	7400cc 7.4L 8 cyl
Mercruiser	Marine	Model 454 Mag MPI (Gen VI)	2001	7400cc 7.4L 8 cyl
Mercruiser	Marine	Model 454 Mag MPI Horizon	2001	7400cc 7.4L 8 cyl
Mercruiser	Engine	Model 454 Mag MPI Horizon (Gen VI)	1998	7.4L 8 cyl
Mercruiser	Marine	Model 496 Mag	2001	8100cc 8.1L 8 cyl
Mercruiser	Marine	Model 496 Mag HO	2001	8100cc 8.1L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.0L (2-BBL) (Gen +)	1998	305cu in 5.0L 8 cyl
Mercruiser	Marine	Model 5.0L (2-BBL) (Gen +)	1998	5000cc 5L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.0L (2-BBL) (Gen +)	1999	305cu in 5.0L 8 cyl
Mercruiser	Marine	Model 5.0L (2-BBL) (Gen +)	1999	5000cc 5L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.0L (2-BBL) (Gen +)	2000	305cu in 5.0L 8 cyl
Mercruiser	Marine	Model 5.0L (2-BBL) (Gen +)	2000	5000cc 5L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.0L (2-BBL) (Gen +)	2001	305cu in 5.0L 8 cyl
Mercruiser	Marine	Model 5.0L (2-BBL) (Gen +)	2001	5000cc 5L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.0L (2-BBL) (Gen +)	2002	305cu in 5.0L 8 cyl
Mercruiser	Marine	Model 5.0L (2-BBL) (Gen +)	2002	5000cc 5L 8 cyl
Mercruiser	Marine	Model 5.0L (Carb.) Alpha & Bravo	2002	5000cc 5L 8 cyl
Mercruiser	Marine	Model 5.0L EFI (Gen +)	1999	5000cc 5L 8 cyl
Mercruiser	Marine	Model 5.0L EFI (Gen +)	2000	5000cc 5L 8 cyl
Mercruiser	Marine	Model 5.0L EFI (Gen +)	2001	5000cc 5L 8 cyl
Mercruiser	Marine	Model 5.0L MPI Alpha & Bravo	2001	5000cc 5L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.7L (2-BBL) (Gen +)	1998	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L (2-BBL) (Gen +)	1998	5700cc 5.7L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.7L (2-BBL) (Gen +)	1999	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L (2-BBL) (Gen +)	1999	5700cc 5.7L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.7L (2-BBL) (Gen +)	2000	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L (2-BBL) (Gen +)	2000	5700cc 5.7L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.7L (2-BBL) (Gen +)	2001	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L (2-BBL) (Gen +)	2001	5700cc 5.7L 8 cyl
Mercruiser	Marine Stern Drive	Model 5.7L (2-BBL) (Gen +)	2002	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L (2-BBL) (Gen +)	2002	5700cc 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L (Carb.) Alpha & Bravo	2002	5700cc 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L EFI (Gen +)	1998	350cu in 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L EFI (Gen +)	1999	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L EFI (Gen +)	1999	5700cc 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L EFI (Gen +)	2000	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L EFI (Gen +)	2000	5700cc 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L EFI (Gen +)	2001	350cu in 5.7L 8 cyl
Mercruiser	Marine	Model 5.7L EFI (Gen +)	2001	5700cc 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L EFI (Gen +) MIE	1997	350cu in 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L MIE	1999	350cu in 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L Ski (CARB)	1998	350cu in 5.7L 8 cyl
Mercruiser	Engine	Model 5.7L Ski (Gen +)	1998	350cu in 5.7L 8 cyl
Mercruiser	Engine	Model 500 EFI	2000	502cu in 8.2L 8 cyl
Mercruiser	Hi-Performance Engine	Model 500 EFI	2000	502cu in 8.2L 8 cyl
Mercruiser	Engine	Model 500 EFI	2001	502cu in 8.2L 8 cyl
Mercruiser	Hi-Performance Engine	Model 500 EFI	2001	502cu in 8.2L 8 cyl
Mercruiser	Engine	Model 500 EFI	2002	502cu in 8.2L 8 cyl
Mercruiser	Hi-Performance Engine	Model 500 EFI	2002	502cu in 8.2L 8 cyl
Mercruiser	Marine	Model 502 Mag MPI (Gen VI)	1998	8200cc 8.2L 8 cyl
Mercruiser	Engine	Model 525 EFI	2000	502cu in 8.2L 8 cyl
Mercruiser	Hi-Performance Engine	Model 525 EFI	2000	502cu in 8.2L 8 cyl
Mercruiser	Engine	Model 525 EFI	2001	502cu in 8.2L 8 cyl
Mercruiser	Hi-Performance Engine	Model 525 EFI	2001	502cu in 8.2L 8 cyl
Mercruiser	Engine	Model 525 EFI	2002	502cu in 8.2L 8 cyl
Mercruiser	Hi-Performance Engine	Model 525 EFI	2002	502cu in 8.2L 8 cyl
Mercruiser	Engine	Model 600SCI	2002	502cu in 8.2L 8 cyl
Mercruiser	Engine	Model 7.4L MIE MPI (L29) (Gen VI)	1998	454cu in 7.4L 8 cyl
Mercruiser	Engine	Model 7.4L MIE MPI (L29) (Gen VI)	1999	454cu in 7.4L 8 cyl
Mercruiser	Engine	Model 7.4L MIE MPI (L29) (Gen VI)	2000	454cu in 7.4L 8 cyl
Mercruiser	Marine	Model 7.4LX MPI (Gen VI) (L29)	1998	7400cc 7.4L 8 cyl
Mercruiser	Marine	Model 7.4LX MPI (Gen VI) (L29)	1999	7400cc 7.4L 8 cyl
Mercruiser	Marine	Model 7.4LX MPI (Gen VI) (L29)	2000	7400cc 7.4L 8 cyl
Mercruiser	Engine	Model 8.1S HO	2001	496cu in 8.1L 8 cyl
Mercruiser	Engine	Model 8.1S Horizon	2001	496cu in 8.1L 8 cyl
Mercruiser	Engine	Model 8.2L MIE MPI (LH) (Gen VI)	2000	502cu in 8.2L 8 cyl
Mercruiser	Marine	Model MX 6.2L MPI	2000	6200cc 6.2L 8 cyl
Mercruiser	Marine	Model MX 6.2L MPI Horizon	2000	6200cc 6.2L 8 cyl
Mercruiser	Engine	Model MX BS MPI Ski	2001	377cu in 6.2L 8 cyl
Mercruiser	Engine	Model MX MPI	2001	377cu in 6.2L 8 cyl
Mercruiser	Engine	Model MX MPI Horizon	2001	377cu in 6.2L 8 cyl

Replaces These Part Numbers

ARROWHEAD	ADR0452, 400-12408
J&N Electrical Products	400-12408

Frequently Asked Questions

Q: Do I need a larger charge wire for a High Output unit?
A: The high amp unit will operate better than stock, but not to its full potential without a larger charge wire. It’s the same reason firetrucks do not use garden hoses. It is IMPARATIVE to have proper charge and ground cables.

Q: Does a High Amp unit cause any damage to my battery or my vehicles charging system?
A: As long as it is installed properly with battery in good condition, then no. A High Output unit works exactly like a factory unit and only produces what is being demanded. No alternator works continuously at full output. Higher amperage is not bad and will not hurt a battery, but high voltage will blow one up.

Q: Will aftermarket underdrive pulleys (crankshaft power pulley) have any effect on my alternator?
A: Yes, underdrive crankshaft pulleys slow all the components (power steering, a/c, and alternator) to provide more power to the rear wheels. In some cases, the charging systems will fall totally on the battery at idle and completely stop charging.

Q: Where is the best place to get a voltage reading of the alternator output?
A: You’ll get the most accurate voltage reading from the back of the alternator at the main charge post that runs directly to the battery. This must be done while the vehicle is running.

Q: Why is the pulley on a high amp alternator smaller than my stock pulley?
A: The smaller pulley advances the power curve of the alternator just slightly, which produces a little more amperage around the idle if needed.

Q: Will I need a smaller belt for my high amp unit?
A: This varies by application because not all belts and belt tensioners are in the same condition. The tensioner will always tell you if you need a new belt or not. If it’s in range, you will not. If it is out, you will. Generally, you will need a belt that is one inch shorter than stock. You should have no problem finding a replacement wherever you buy your parts. V belt applications simply re-adjust your belt tensions to 3/8” deflection.

Q: What is the difference between a one wire, self-exciting and a self-energizing regulator?
A: Nothing. They are all exactly the same. Different manufacturers use different terms for marketing. The only wire to hook up is the charge wire to the battery. This does require modification for the alternator charge light on the dash.

Q: My stock unit used a five-groove pulley, and you sent my high amp alternator with a 6 groove. Why and what can I do?
A: 5 groove overdrive pullies are not produced. Install the belt on the back groove of the pulley closest to the fan or body of the alternator. The fan is internal, and this application will work just fine.

Q: Can your alternator be run in dual or triple alternator applications?
A: Yes. When wired and mounted correctly, the alternator can run in either dual or triple applications.

Q: Will I need a new battery with a high amp alternator?
A: If your battery is in good condition, and in spec of its OEM rating, then no. Your battery should work equally well with either the OEM and a High Amp unit.

Customer Reviews

WARNING: California’s Proposition 65

Alternator for Mercruiser 400-12408

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