New Altenator Putting Out 15.25 volts, Is That OK?

I had a new altenator installed and it's putting out 15.25 volts (stbd engine), the port engine original alternator putting out 14.25. Is the 15.25 OK or too high?

Related note, I'm only getting 12.8 to the batteries so I'm looking at connections and cleaning up the corrosion. The starboard engine had salt water sprayed on it when the hose clamps on the entire motor were not properly tightened after the engine was removed for a sterndrive repair, and was cruised 25 miles down the coast before a little voice inside my head thought to stop, raise the engine hatch and have a look to make sure all was ok. It was not, but fortunately we didn't have a hose come off.

I had a new altenator installed and it's putting out 15.25 volts
I'm only getting 12.8 to the batteries

So what is the correct one? 15.25 will cook the batteries but 12.8 means not charging

Do they use a sense circuit and where is it connected?
post a pic of the terminals on the alternator.

louc said:

Do they use a sense circuit and where is it connected?
post a pic of the terminals on the alternator.

Click to expand...

Altenator terminal picture attached. Not sure if there's a sensing circuit.

Also attached is what I think is the negative battery to the engine block. It did not appear corroded but I removed it, cleaned and treated with CorrosionX. Negative battery connection to main DC negative bus is also clean and tight.

After cleaning engine connection charging voltage at the battery is up to 13v.

The smaller black wire on the engine post is significantly thicker than the wire coming off the alternator, so I'm thinking it must be from the starter motor?

Next time at boat I will trace the negative wire from the altenator to where it connects to the engine and/or negative battery path by gently opening up the wiring harness.

I'm thinking that the voltage drop from altenator to battery must be due to corrosion or short somewhere along the line?

Thanks
Jeff