Battery ?

[NOTGSXR]

Apparently you haven't been part of the countless pages of discussions on this... and compared to some other outboards .. the Optimax engines are indeed power hungry.. Again.. this really is an area where excess is a wise choice...

In other pages on that thread or another thread.. many actually... the Duracell (Deka) from Sams Club was brought up.. it has 800 CCA's. Don has specifically stated that this battery meets the minimum requirements for the engine only... he went further to say using livewells and electronics will cause problems.

But again... more power too you!

[CatFan]

Apparently you haven't been part of the countless pages of discussions on this... and compared to some other outboards .. the Optimax engines are indeed power hungry.. Again.. this really is an area where excess is a wise choice...

In other pages on that thread or another thread.. many actually... the Duracell (Deka) from Sams Club was brought up.. it has 800 CCA's. Don has specifically stated that this battery meets the minimum requirements for the engine only... he went further to say using livewells and electronics will cause problems.

But again... more power too you!

Again, the entire thread is about the digital throttle on Verado engines. Google the service bulletin. Not Optimax at all in any way. Optis crank much easier than Verados.

[NOTGSXR]

I know it was about Verados in the Bulletin.. I'm not trying to argue the point lol.. The 250 Opti's however also require a good bit of juice initially. Here's a snapshot of a post from Don and the poster has a 2004 250xs..
IMG_20171102_23783.jpg

He states:

Re: Low voltage alarm when trimming with motor running (canadablazer)
LOAD TEST THAT BATTERY to confirm it's ACTUAL capacity.

Note: 1000 MCA is the BARE MINIMUM capacity for your ENGINE ALONE. Running a battery of the capacity leaves NO RESERVE for additional electronics (pumps, livewells, graphs, or power hungry side-imaging sonar devices).

I believe you'll find that upgrading batteries will help to solve your problem- see the following post for more information on RECOMMENDED BATTERIES:

http://www.bbcboards.net/zerot...st-in



Dual Mercury Master Technician- for Mercury Outboards, Racing & Mercruiser Sterndrives in Greenville, SC.
Still consider myself a "Marine Apprentice" after 40 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

[NOTGSXR]

It is just a good idea to go big imho.

[fishnfireman]

A 300 XS calls for a (minimum) 1000 MCA - 800 CCA
I've owned two different batteries that failed to start my motor even though they claimed to meet those requirements.. Both times it was on a very cold morning.. Even on warm mornings that first start would make you wonder... After buying a battery that Don's article said (met the requirements) I've had no more failed starts.
This opti takes a lot of right now juice to crank.

[fishnfireman]

Way more than on Opti requires. Merc suggests 800MCA for an Opti. People have misread Don's post, which is for Verados. More is of course better when the charging system can handle it considering the loads on a bass boat, but even an Interstate 24M-XHD is plenty for cranking an Opti.

Not what my Mercury service manual calls for "1000 (minimum) MCA"

[NOTGSXR]

What do you Allison owners know

[NOTGSXR]

A 300 XS calls for a (minimum) 1000 MCA - 800 CCA
I've owned two different batteries that failed to start my motor even though they claimed to meet those requirements.. Both times it was on a very cold morning.. Even on warm mornings that first start would make you wonder... After buying a battery that Don's article said (met the requirements) I've had no more failed starts.
This opti takes a lot of right now juice to crank.

Thank you for articulating something i was having difficulty with!