[aliyilmaz]

Hi
I want it to see if any one had a same problem with my alternators . My belt keeps snapping . Tech told me bad alternator and i had it rebuild . My engine battery is not charging full and while engines warm i get this screaming bearing sound then belt snaps . Some one told me alternator may be locking up due to isolator being bad ? Does any body had a same type of problem?

Thx

[Chris Burkard]

What engines and what year is the boat.

Clearly the alternator is bad or some component of the charging system is causing the alternator to lock up. I'm guessing the sound you hear is not bearing noise, but the alternator magnetic field overpowering the belts ability to turn the pulley and causing slipping of the belt. When it gets hot enough, the belt fails.

Early 31s used a traditional alternator and flooded cell batteries (lead acid). I'm not sure of the year, but at some point, Tiara switched to GEL batteries which require a different charging rate, so the standard internally regulated Alternators were removed from the engines when purchased and Bal Mar Alternators with external regulators were installed by Tiara. These alternators tend to have more issues than the standard internally regulated variety as they age. If you have a GEL battery system, you can't go back to a traditional alternator unless you convert the complete system.

Do you have GEL Batteries? This will tell us how you should proceed.

Sincerely,

[bilgerat]

Another possibility to consider is the conditon of the pulleys. Sounds as though ( from the post) there is charging taking place, then the noise and finally the belt breaks. How long does this process take? If it starts charging and the pulleys are rusted and damaging the belts, then with the alternator under load the belts start to slip until failure. I've got a 31 open and if it's the port alternator removing it for service aint no picnic.