The C-Brats Forum Index
HomeForumsMy TopicsCalendarEvent SignupsMemberlistOur C-DorysThe Brat MapPhotos

Dual motor start batteries

 
Post new topic   Reply to topic    The C-Brats Forum Index -> Electrical and Wiring
View previous topic :: View next topic  
Author Message
pcg



Joined: 31 Aug 2018
Posts: 405
City/Region: Sherwood
State or Province: OR
C-Dory Year: 1999
C-Dory Model: 22 Cruiser
Vessel Name: C-Quest
Photos: pcg
PostPosted: Sat Apr 16, 2022 2:27 pm    Post subject: Dual motor start batteries Reply with quote

So for a dual motor setup - like two Honda 60s, how many start batteries are used? Can a single battery be used to start both engines, one at a time? And both motors then charge the single battery?
_________________
Paul
Back to top
View user's profile Send private message
C-Wolfe



Joined: 16 Sep 2020
Posts: 241
City/Region: Anchorage
State or Province: AK
C-Dory Year: 2006
C-Dory Model: 22 Cruiser
Vessel Name: C-Wolfe
Photos: C-Wolfe
PostPosted: Sat Apr 16, 2022 5:14 pm    Post subject: Reply with quote

I don’t think it is good to have two alternator charging the same battery, they don’t play well together and tend to fail early/more often on this kind of setup.
_________________
Stephan B.
C-Wolfe 22 C-Dory cruiser 2020- present
No Name; Bayliner explorer 26 2012-2015
sparkle; Ericson 25 CB 2008-2012
Sculpin; Drascombe Drifter 2005-2008
Back to top
View user's profile Send private message Send e-mail
thataway



Joined: 02 Nov 2003
Posts: 20778
City/Region: Pensacola
State or Province: FL
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: thataway
Photos: Thataway
PostPosted: Sat Apr 16, 2022 10:01 pm    Post subject: Reply with quote

I would rig the setup for one engine to charge the start battery and one the house battery if dual 60's. If you have more than one house, then the second off the motor charging the start battery with a automatic charging relay.
_________________
Bob Austin
Thataway
Thataway (Ex Seaweed) 2007 25 C Dory May 2018 to Oct. 2021
Thisaway 2006 22' CDory November 2011 to May 2018
Caracal 18 140 Suzuki 2007 to present
Thataway TomCat 255 150 Suzukis June 2006 thru August 2011
C Pelican; 1992, 22 Cruiser, 2002 thru 2006
Frequent Sea; 2003 C D 25, 2007 thru 2009
KA6PKB
Home port: Pensacola FL
Back to top
View user's profile Send private message Send e-mail
Hunkydory



Joined: 28 Mar 2005
Posts: 2652
City/Region: Cokeville, Wyoming
State or Province: WY
C-Dory Year: 2000
C-Dory Model: 22 Cruiser
Vessel Name: Hunkydory
Photos: Hunkydory-Jay-and-Jolee
PostPosted: Sat Apr 16, 2022 10:58 pm    Post subject: Reply with quote

We have twin Honda 60’s & before them, back to 2003, Honda 40’s. Same simple set up, which was done originally by the then factory & then used for both sets. Each motor has its own start battery & for the house, either starting battery #1, #2 or combined can be used, which is chosen by using a Perko 1, 2, combined or off switch.

With the Honda 40,s when doing a lot of rpm changes with the batteries combined it twice caused a charge coil on one motor to burn out. I was told when switching to the Honda 60’s the burning out of the charge coil problem when batteries were combined had been corrected. Not wanting to find out again in a remote location if that was true, I now only combine the batteries to the house, when running the windless or if batteries on the low side to start the Wallas. The Honda 40 only had 10 amps of output, so when doing mostly displacement speed on one motor, the Honda 2000 generator was a big help. I still carry the Honda generator on a long cruise, but now it’s very seldom used with the Honda 60’s putting out 22 amps apiece.

The two batteries are AGM size 24.

Probably better ways as Bob suggest to do it, but I'm satisfied with the present set up.

Jay

_________________
Jay and Jolee 2000 22 CD cruiser Hunkydory
I will not waste my days in trying to prolong them------Jack London
https://share.delorme.com/JuliusByers
Back to top
View user's profile Send private message Send e-mail
bridma



Joined: 13 Sep 2011
Posts: 1155
City/Region: Comox
State or Province: BC
C-Dory Year: 2009
C-Dory Model: 22 Cruiser
Vessel Name: Nomad
Photos: Nomad
PostPosted: Sun Apr 17, 2022 12:48 pm    Post subject: Reply with quote

[quote="Hunkydory"]We have twin Honda 60’s & before them, back to 2003, Honda 40’s. Same simple set up, which was done originally by the then factory & then used for both sets. Each motor has its own start battery & for the house, either starting battery #1, #2 or combined can be used, which is chosen by using a Perko 1, 2, combined or off switch.


That was my set up with twin 40 Yamis. Worked just fine. I thought that was the normal set up.

Martin.
Back to top
View user's profile Send private message Send e-mail
hardee



Joined: 30 Oct 2006
Posts: 12632
City/Region: Sequim
State or Province: WA
C-Dory Year: 2005
C-Dory Model: 22 Cruiser
Vessel Name: Sleepy-C
Photos: SleepyC
PostPosted: Mon Apr 18, 2022 3:35 am    Post subject: Reply with quote

Jay and Marti's set up is the same as mine for twin Yami 40's. BUT, I am running 2 Group 29, FLA RV Deep Cycle batteries. I run on both most of the time, but each engine charges its own battery and they start off the both switch.

That was the original setup buy the original owner. I was his 43rd and last boat. I think he knew what he was doing.

Harvey
SleepyC Moon


_________________
Though in our sleep we are not conscious of our activity or surroundings, we should not, in our wakefulness, be unconscious of our sleep.
Back to top
View user's profile Send private message
pcg



Joined: 31 Aug 2018
Posts: 405
City/Region: Sherwood
State or Province: OR
C-Dory Year: 1999
C-Dory Model: 22 Cruiser
Vessel Name: C-Quest
Photos: pcg
PostPosted: Mon Apr 18, 2022 10:43 am    Post subject: Reply with quote

hardee wrote:
each engine charges its own battery and they start off the both switch.

This sounds like the best setup. Thanks everyone.
Back to top
View user's profile Send private message
T.R. Bauer



Joined: 17 Nov 2007
Posts: 1726
City/Region: Wasilla
State or Province: AK
C-Dory Year: 1993
C-Dory Model: 22 Cruiser
Vessel Name: C-Whisperer
PostPosted: Mon Apr 18, 2022 5:59 pm    Post subject: Re: Dual motor start batteries Reply with quote

pcg wrote:
So for a dual motor setup - like two Honda 60s, how many start batteries are used? Can a single battery be used to start both engines, one at a time? And both motors then charge the single battery?


Some people will say it's ok if the outboards are identical. I do not agree - I say a battery for each engine and completely isolated from each other.
Back to top
View user's profile Send private message Send e-mail
kaelc



Joined: 19 Jul 2017
Posts: 411
City/Region: Saanich
State or Province: BC
C-Dory Year: 2007
C-Dory Model: 25 Cruiser
Vessel Name: Island Magic
Photos: Stil-Afloat
PostPosted: Wed Apr 20, 2022 12:04 am    Post subject: Reply with quote

I’d do a group 31 AGM marine combo deep cycle starting for the house battery and a 24 marine starter for the other. If you want to have an onboard charger go agm for both. That way if the house gets drawn down it can still start and will also last a long time vs a flooded lead acid deep cycle. That’s what I have.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    The C-Brats Forum Index -> Electrical and Wiring All times are GMT - 5 Hours
Page 1 of 1

 
     Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum



Page generation time: 0.0837s (PHP: 83% - SQL: 17%) - SQL queries: 27 - GZIP disabled - Debug on