1998 Johnson 200HP high voltage

[184champ]

Took the boat I bought a couple months ago out yesterday and the volt gauge reads 18 volts running full throttle, but tach read only 4000 rpm is this a bad voltage regulator??

Thanks

[SEAHORSE]

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 184champ &raquo;</TD></TR><TR><TD CLASS="quote">Took the boat I bought a couple months ago out yesterday and the volt gauge reads 18 volts running full throttle, but tach read only 4000 rpm is this a bad voltage regulator??

Thanks</TD></TR></TABLE>

Possible regulator, but what does the voltmeter read with the key ON and the motor OFF?

If there are wing nuts holding the battery cables, get rid of them ASAP and use stainless steel nuts and lockwashers.

[184champ]

12 volts key on engine off, 13 at idle, 18 high rpm.

[SEAHORSE]

To double check the accuracy of the gauge, put a digital voltmeter on the battery terminals and run the motor. A weak or partially sulfated battery can also make a higher than normal voltage. Check all the obvious items, and then replace the rectifier if needed.