This alternator is built for marine engine applications as a Delco 10SI type conversion unit, supplied to replace the original Prestolite-pattern alternator fitted to many marine engines including Chris Craft, OMC, Mercruiser, Universal, Flagship, Dearborn and Owens Yacht installations. It is the dual top ear version, giving an alternative mounting arrangement to the single top ear conversion.
It is manufactured to OEM specifications for output and mounting, with high-temperature epoxy and grease for durability, an external fan (EF) cooling design and internal regulator (IR). Output on this version sits in the 61-78 amp range depending on manufacturer.
Key Features
- 12-volt marine alternator
- 61-78 amp output (Delco 10SI type)
- Dual top ear mounting
- Designed to replace Prestolite units
- Internal regulator (IR), external fan (EF)
Technical Specs
| Specification |
Detail |
| Voltage |
12V |
| Amperage |
63A (61-78A range) |
| Mounting |
Dual top ear |
| Fan Type |
External Fan (EF) |
| Regulator |
Internal Regulator (IR) |
Vehicle Fitment Guide
Years shown are the overall coverage span for this part. Please confirm against the OEM part number on your original unit before ordering.
| Make & Model |
Years |
| Chris Craft, OMC, Mercruiser, Universal, Flagship, Dearborn & Owens Yacht Marine Engines (2.5L-7.0L) |
1961-1981 |
OEM Part Number Cross Reference
Aftermarket replacement. OEM part numbers are listed for reference only.
| Part Number |
Manufacturer / Brand |
| ADR0395 |
Arrowhead |
| 8903 / 8903N-61A |
Lester |
| 18-5954 |
Sierra Marine |
| 40112 |
Arco Marine |
| 20037 |
API Marine |
Frequently Asked Questions
Will this fit my marine engine without modification?
This is a Delco 10SI type conversion designed to replace Prestolite-pattern alternators with dual top ear mounting - check your original unit's mounting arrangement matches before ordering.
What is included?
One new 12-volt Delco 10SI type marine alternator, ready to fit.
How do I know my old alternator has failed?
Signs include a charge warning light, a battery that discharges even with the engine running, dimming instruments or lights, or a grinding/whining noise from the unit.
Is a higher amp version available?
Yes, a 94 amp version of this Delco 10SI conversion unit is also available separately.
Dispatched from the UK · 12-month warranty · Fitment support from our technical team
