low voltage when starting

[oddysea1]

This is a 350 mercruiser magnum -when I turn key to on position to start the volt meter barely moves it indicates low voltage on my guage-it starts and runs rough again showing little charging-battery is fully charged.Is there a way to check guage-alternator or any thing else that deals with providing power to the starter and engine-this is a twin screw and the battery switches are on all - Thank you Andy

 

[Bondo]

Ayuh,...... Check all yer Ground connections,......

A multi-meter can cross-check the dash gauge,.....

 

[oddysea1]

Any chance of giving a quick tutorial on how to check volt meter -my mechanic does say his scanner says system is putting out 14.1 volts.

 

[Bondo]

Any chance of giving a quick tutorial on how to check volt meter -my mechanic does say his scanner says system is putting out 14.1 volts.

Ayuh,...... Set yer multimeter to volts, DC,.... Touch the red lead to the positive, 'n the black lead to the ground,....

The multimeter should show the same voltage as the voltage gauge,......

 

[vetting]

I've seen a lot of times that the terminal connectors on the 5.7 alternator fray or break due to vibration - especially the large orange wire. Also, disconnect all of the large black wires from the battery and where they lead and sand down the terminals and reconnect.

 

[achris]

Not clean....



Clean... (enough to eat off!)