Westerbeke tachometer issue

[Dulcesuenos]

Have twin 12c-2 westerbekes. First one tach was slow to respond. Would come on after a few minutes of running now the other is doing it. If you rev. The engine a tiny bit they start working faster. Any ideas?

[GordMay]

See page 24 ➥ http://www.westerbeke.com/OnlineManu....%20Manual.pdf

[NCboatrx]

This is likely an alternator issue or a bad connection on the wire from the AC terminal at the back of your alternator (may be labeled W) to the tachs. Also check the plugs in the panel harness for corrosion.