Mercruiser 165 alternator mashup?

[FarmYard]

Looking for a new alternator for my 165 I6 4.1L
Numbers on current alternator are 1102479 55 amps
only numbers that match are from a car alternator. could this be a mash up?
will a DB Electrical 400-12007 1-Wire Marine Alternator 42 amp work in its place?

View attachment PXL_20231030_073424203.jpgView attachment PXL_20231030_192621106.jpg

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[flashback]

It should, and count your blessings, the auto alt is a very bad idea..

 

[alldodge]

Your ALT should be part number 78403A2 which is item 11
https://www.mercruiserparts.com/bam/subassembly/30959/1605/2

Never use Auto ALT on a boat

It's no long made by Merc but can be found easy just search "Mercruiser 78403A2" and some will show up. Amazon has one for $140 but suggest going to NLA Marine, they have one for $60

https://www.nlamarine.com/products/...3a2-omc-0982364-delco-remy-3-wire-10si-42-amp

 

[flashback]

The alternator is cooled by a fan and fumes in the bilge will be pulled into it. It has spark from the brushes that could have blown you up. The marine alt has screens in the vents that are meant to dissipate any flame. I believe the aircraft industry uses oil cooled units. Jmho

 

[Bondo]

will a DB Electrical 400-12007 1-Wire Marine Alternator 42 amp work in its place?

Ayuh,...... Welcome Aboard,..... Yes, that'll work,.....
It looks exactly like the one in yer attachments, which is a screen protected marine unit,....

 

[flashback]

I've heard talk of brushless alts that don't spark. Probably cost an arm and leg..

 

[FarmYard]

Thanks for all the replies. Yes, I wouldn't put an auto starter in a boat. I just picked up this boat and am redoing everything. Mabey the last guy mashed 2 alternators together because I ripped out so much stereo equipment and wires. It even had a electric fuel pump wired in totally wrong, not the right carb with a Mr. Gasket carb spacer that did not even cover the manifold hole, no shift switch interrupt, and countless other hackery. The Sealoc stern drive repair manual is getting put to good use. I'm gonna save this 1978 Apollo relic one way or another.