1998 Force 120 - Cranking Amps

[buzzbomber]

Sup all,

I've got dual batteries set up on a perko switch and have took a wire brush and contact cleaner and cleaned up all connections from motor to switch to battery.

Battery 1: 1000 MCA starting battery, 2-3 cranks engine is up and smoking : )

Battery 2: 870 MCA AGM battery (optima) - 2 week cranks then quits.

The Battery 2 took a trickle charge fine and looks pretty much brand new. It runs the electronics on the boat all day just wont crank more than once or twice.

Main question is if the Optima I have is under powered for the 120 force? or is there something else it could be? would hate to get rid of the battery if I don't need to (sells for $180+).

If it's under powered anyone have a good recommendation for a replacement? something that wont break the bank but reliable and will give me a clean start.


Appreciate any advice.

 

[Cannondale]

Re: 1998 Force 120 - Cranking Amps

I cannot imagine that your 870 MCA battery is underpowered for your motor. The books I have say Force recommended a minimum of 490 MCA/630 CCA for their motors, so your battery is well over the minimum recommendations.

Have you had the battery actually checked by a shop on a tester? Even if it takes a trickle charge, that doesn't mean it's fine. And from what I've read over time, a lot of people are complaining of shorter and shorter life from their Optima batteries....claim the quality isn't what it once was with them.


Just one question, though. What brand of voltage regulator are you running on the motor? Only ask because while looking at a CDI replacement for my 70hp Force, which uses the same CDI replacement as your 120hp motor, CDI specifically mentions NOT to use an AGM battery with it. Probably irrelevant, but just curious.

DO NOT USE A MAINTAINENCE FREE, AGM OR DRY CELL BATTERY WITH THIS TYPE REGULATOR/RECTIFIER!!!

http://www.cdielectronics.com/InstallSheet/194-5279.pdf

 

[buzzbomber]

Re: 1998 Force 120 - Cranking Amps

Thanks Cannon,

Busted out my clymers and saw that big warning sign just now to. So does this mean that it recommends using only flooded batteries? Can't use Gel or AGM?

Looks like i'll take the battery to local shop and see if they can load test it. If it doesnt check out new battery time. But now i'm wondering if I have to swap it out regardless?

What battery make/model are you or anyone else using?

As far as the regulator goes not entirely sure, just picked up the boat/engine about 2 months ago. Only has about 250hrs on it so it's probably just the oem version.

 

[roscoe]

Re: 1998 Force 120 - Cranking Amps

Use any flooded battery, maint free or not, 550 cca = 715 mca

cca x 1.3 = mca

And, your motor has a cdm ignition , not cdi.

 

[Cannondale]

Re: 1998 Force 120 - Cranking Amps

Personally, I'm using a pair of flooded, regular old deep cycle batteries on mine. A group 24 dual purpose for the motor/starting system/electrical system, and a group 27 for my trolling motor. I was just too cheap to buy an Optima and I got more available power for less $$. True, they're heavier, but we're dealing with old tech when using Force motors, so it gets an old tech battery. Yours was one of the last years Force was produced and may be tolerant of an AGM-type battery.....but the old style flooded batteries are appropriate for any situation.

 

[jerryjerry05]

Re: 1998 Force 120 - Cranking Amps

$20 Harbor Freight.I have regular batteries 550CCA I used the boat 2 weeks ago and somehow left the backup depth finder on.
I went out yesterday to do something on the boat(going out today).The motor still cranked over after 2 weeks.

 

[steveclv]

Re: 1998 Force 120 - Cranking Amps

Well although I have a pair of 24's in the boat - I carry a fully charged lawnmower battery as a last ditch emergency - just connected to a solar panel. It's only 145 CCA but it still starts my Chrysler 125 - I'm sure it's not going to run for more than a few starting attempts but it will spin the motor. So your batteries should be man enough by far assuming that they haven't failed internally.

 

[buzzbomber]

Re: 1998 Force 120 - Cranking Amps

Cool, thanks for all the input, will be testing the optima this weekend and if that doesnt check out (I suspect it's bad) i'll probably pick up a group 24 battery to act as my 2nd.

 

[Gone4two]

Re: 1998 Force 120 - Cranking Amps

I have two Optimas, and they are GEL. One went bad, so I took it back to PepBoys. They replaced it for free. The store manager mentioned that these batteries were designed "Not to Fail", and that they have a hard time getting credit from the manufacturer (Johnson controls). He also mentioned that many people do not know that they are gell batteries and try to charge them as a flooded battery. This will cause premature failure in these batteries. Additionally he mentioned that once they stay undercharged for a while, it is very difficult to get them back to full charge. I have not had any problems other than that I also have a force 120.

Gone4two