Need help finding Mercruiser alternator

[Gustuv Wynd]

I have an alternator on a 5.7 Mercruiser Thunderbolt 4 engine that looks like the bearing is going out. Figured I'd replace my alternators.

The model number on it is 8EM2003KA...no part number or other important number that I can see.

Of course, I hand that model number over to the Internet along with various other keywords like mercruiser and alternator and such and it tells me that no such thing exists.

I am 99% sure this one will be a replacement:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

...but I don't suppose any one has a look up chart of such things, or just knows from experience, that might let me know for certain?

It's going on 1988 Welcraft St. Tropez if that matters...the date field isn't stamped on the alternators, but I find it unlikely that they are the originals...could be though. The boat hasn't seen a lot of use and I just purchased it late last year.

Thanks

[DougR]

Try Arco Marine.

DougR

[Gustuv Wynd]

Gah! Just found it. That Amazon link should work. 817119A1 is the replacement for 8EM2003KA in case any one finds this post in the future.

Found info here:
https://www.marineengine.com/parts/m...rola-8em2003ka

[Lepke]

You can buy rebuild kits for most alternators and if there isn't a kit you usually can buy the individual parts. The bearings are the easiest to find.

[skipmac]

First, be aware that Mercury does not make alternators. They probably come from someone like Delco or Mitsubiahi or Hitachi and then are marine adapted by adding flame and spark arresting.

As mentioned, you can buy kits to overhaul and alternator but if you don't want to do it yourself any auto alternator shop can do it cheaply. Just make sure they understand it's going on a boat and they don't remove the fire preventing bits.

[a64pilot]

Yes, for sure take it to an alternator shop, it will be repaired for a fraction of the cost, and it won’t be a cheap Chinese knock off.

[wingless]

When my Mercruiser alternator died, I purchased an identical appearance marine part that was listed to fit my engine from eBay.

The dead Mercruiser part and the replacement aftermarket part looked identical.

Each had a “Made in” sticker from a different Asia country.

No issues after several years.