[C320-list] No charging until engine is revved repeatedly

[sholdr at aol.com]

it is not unusual for an alternator not begin to generate a charging amperage until the rpm are great enough to charge the coils enough to do so -- once tis level is reached it will continue to create a charging voltage unless turned off...  -----Original Message-----
From: Bob Hoyt <rehoyt at gmail.com>
To: c320-list <c320-list at lists.catalina320.com>
Sent: Wed, May 1, 2019 7:44 pm
Subject: [C320-list] No charging until engine is revved repeatedly

I posted this problem two years ago without resolution and since then
nobody seems to have the answer. I have a 1994 320 with a Perkins M30
engine and Lucas Marine alternator 55 Amp.

When I start the engine there is no output from the tach or voltmeter
unless I "goose" the engine up several times (after a minute or two of
running) then that wakes up the alternator and it reliably puts out 14.2
volts. The idling speed is 1050 rpm and the green charge light stays on
until the alternator kicks in. The voltmeter usually reads 12 volts. I have
four new golf batteries and they are topped off with a solar panel and MPPT
controller.

This week I took the alternator off and took it to a marine alternator
specialist who claimed everything tested normal on his testing workbench.
He wanted me to be sure that the small brown wire that is the "exciter"
registered at least 2 volts and it registered 12.9. I confirmed that this
wire goes to the charge light in the engine panel and that is exactly where
it is supposed to go according to the schematics. I can find no other
problems and none of the marine electricians have a clue. There is a
disconnected pink wire that leaves the engine panel and runs down as far as
the voltage regulator of ? significance. It does appear that over time that
I have to rev the engine at even higher rpms several times for the
alternator to work. I would appreciate any thoughts.

Bob Hoyt
Hull #58 Ikigai
Pensacola, FL

-- 

*Robert (Bob) Hoyt MD FACP*

*CAPT (Ret) USN*

*Associate Clinical Professor, Department of Internal Medicine*

*Virginia Commonwealth University*

*Richmond, VA*

*---------------------------------------------------------------------------------------------*

*Adjunct Associate Professor, College of Allied Health Professions*

*University of Nebraska Medical Center*

*Omaha, NE*

*Diplomate, Clinical Informatics*

InformaticsEducation.org  <http://InformaticsEducation.org>
rehoyt at gmail.com

robert.hoyt at unmc.edu <robert.hoyt at unmd.edu>

robert.hoyt at vcuhealth.org

Cell: 850-384-5235