Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
ARCO Marine Zeus A275L J180 4" Alternator w/Isolated Ground Regulator [4025]Zeus A275L J180 4" Alternator with Isolated Ground & Regulator The highest power output alternator in its size class. Features: Engineered for high energy production. Suitable for marine, RV, military, and commercial applications. Rapidly charges large battery banks. Coolest operating temperatures for increased performance. Heat shedding coatings Rectifier located on housing exterior Dual cooling fans OEM components Optimized for performance at idle
Zeus A275L J180 4" Alternator with Isolated Ground & Regulator
The highest power output alternator in its size/class.
Features:
- Engineered for high energy production.
- Suitable for marine, RV, military, and commercial applications.
- Rapidly charges large battery banks.
- Coolest operating temperatures for increased performance.
- Heat shedding coatings
- Rectifier located on housing exterior
- Dual cooling fans
- OEM components
- Optimized for performance at idle speeds.
- Reduces the need for a generator by creating additional power with your engine.
- Unleash peak performance with E-Coat/Cerakote, keeping the A275L cooler for sustained amperage output.
- Use the ARCO Zeus Bluetooth Alternator Regulator for maximum performance or lithium battery charging.
- SAE J1171 Certified.
- Models are available with an internal/external voltage regulator.
- Proudly made in the U.S.A.
Technical Specifications:
- Voltage - 12v
- Field Type - P
- Rotor Poles - 16
- Stator Size - 138mm
- Frame Size - Large
- Weight - 14.9 lbs/6.7 kg
- Regulation - Internal/External (Internally regulated with adaptor for optional external regulation.)
- Output Voltage - 14.1v (Default)
- Finish - (Black) Cerakote or E-coating
- Cut-In RPM - 1,061 Alternator RPM
- Maximum Alt RPM - 19,000
- Battery Post - M8 Thread Post, Side Mount
- Standard Pulley - 49K6 (6-groove, 49mm)
- Pulley Mount - 17mm diameter shaft, 25mm long, threaded M17 x 1.5
- Pulley Hardware - M17 x 1.5 x 24mm nut, w/ 18mm ID x 29mm OD washer (Included)
- Diodes - 6 positive, 6 negative, 50A Rated, Avalanche
- Max Output (Cold, 9,000 RPM) - 311 Amps
- Sustained Cruising Output (Hot, 6,000 RPM) - 227 Amps
- Sustained Idle Output (Hot, 3,000 RPM) - 198 Amps
- Max Continuous Operating Temperature - 110°C / 230°F
Mounting Application:
- Replaces most Volvo Penta alternators using a 4” J180 saddle-style mount
Quick Guide (pdf)
Brochure (pdf)
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.5 ★★★★★
Based on 783 reviews
Sort
Product Reviews
★★★★★ 5
Good quality sound deadener at a good price.
Model: NewSLS50_52
Quality sound deadening that adheres to body panels well. You can easily hear the vibration reduction after just the first piece by tapping on the body panel before and after.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 21, 2025
★★★★★ 4
Good stuff at a good price
Model: NewSLS50_52
Works well and sticks well. I used a roller and it has been over a year and everything still sticking as good as day i put it everywhere. I didnt use any adhesive but I did wipe everything down with acetone before I applied. Good stuff at a good price
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 23, 2025
★★★★★ 5
Good value
Model: NewSLS50_52, Model: NewSLS50_52
Working perfectly. Install of stereo equipment and carpet left me wanting some heat and sound resistant materials.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 23, 2026
★★★★★ 5
BUY THIS ONE!
Model: NewSLS50_52
This is one of the good ones. There are other brands just as good, and manny brands are worse, but this handles well, rolls down easily, doesn't come off at all easily, and adapts to dips and curves like a champ.
Appropriately heavy and dead, I'm happy with the way it smothers panel resonances and even at muffling direct sound, like a big hand over my Uncle Harry's eternally noisy mouth. You can rip the foil but you have to work hard at doing that.
Remember to buy a brayer; you can roll overlaps nice and thin. Also remember to pre-wipe the sheet metal with a decent solvent like acetone or Stoddard/Varsol. It should last forever.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 26, 2025
★★★★★ 5
Good stuff, but watch the temp
Model: NewSLS50_52
I used this in my single cab pickup truck (89 ford.) It only took half the box (10 sheets or 25 square feet) to do the floors, but I bought the big box because I plan to do the doors, back wall, and maybe the roof as well. One thing I learned is that the temperature matters when you’re doing the installation. It was around 55F when I started in the evening, and when it dipped down into the 40s the sheets would not stick to the metal, and were hard to compress with the roller. That’s why I ended up only doing the floors and not any vertical surfaces; i will have to wait for a nice hot day. The other thing is that the foil layer on top is razor sharp at the edges, definitely wear gloves! I didn’t notice until after but I have little papercuts all over my fingers. Aside from those things, the install was easy and straightforward. The sheets cut easily with scissors, and any goo that ends up on your hands or scissors can be cleaned up with acetone (nail polish remover), or lacquer thinner. I would use this stuff again.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 16, 2023