From the manual here:
http://www.fourwinns.com/uploads/2017/2/318-Vista.pdfPort Engine Battery Switch:
“ON” - Turning the switch to position “ON” will use the port engine battery to power the port engine and 12 volt engine related equipment. The ships system battery will not be used for any engine related equipment, but will power all other 12 volt equipment on the boat. The isolator will allow any alternator to charge all three batteries. “ON” is the recommended switch position for normal boat operation. This position allows maximum use of 12 volt equipment on the boat.
Starboard Engine Battery Switch:
“ON” - Turning the switch to position “ON” will use the stbd engine battery to power the stbd engine and 12 volt engine related equipment. The ships system battery will not be used for any engine related equipment, but will power all other 12 volt equipment on the boat. The isolator will allow any alternator to charge all three batteries “ON” is the recommended switch position for normal boat operation. This position allows maximum use of 12 volt equipment on the boat.
Emergency Start Procedures:
If one of the designated engine batteries fails to start its respective engine, engage the “EMERGENCY START” switch at the helm and attempt to start the engine. Current is drawn from the other batteries to start the engine. Once engine has been started return the “EMERGENCY START” switch to the “OFF” position. Once back at port, be sure to have the failed
engine battery checked out for possible service or replacement.
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Chris and Alicia
Las Vegas, NV
ALTIVA
1996 Four Winns 238 Vista Dlx 5.8Fi