What size starting battery is standard ?

[QBhoy]

Guys

The manual might be able to tell me, but it?s not to hand.
What size (AH and CCA) battery are most using to start their small block v8?s ? Mine seems very small in size, but seems to do the job. It?s a 85ah and can?t remember the CCA, but it is purely a starting battery.

 

[bman440440]

here is what the manual states for my 4.3 v6 "Minimum Battery Requirements 375 cca / 475 mca / 90 Ah " it shows the same for the 305/350 non FI engines as well... however IMO never run less than 550 cca / 650 mca battery... the AH are not as important for a starting battery... I personally run two grp 31 AGM's (800 cca/ 1000 mca) 1 for starting 1 for house with an ACR

 

[alldodge]

Seem to remember you have a 350MPI (should put it in your sig) and the manual calls for minimum of 550CCA, 825MCA and 150Ah. When I look for a bat I get the largest capacity I that will fit in the bat box. Always get AGM's now

 

[QBhoy]

Cheers Guys. I?m pretty sure the CCA on this battery is 700 and something. I just worry that the small AH won?t provide enough sustained juice should I ever need it.
I serviced it mid season and for some reason my head was in carb mode and not MPI mode. The engine took a big slug of air from the empty fuel filter and I kept turning key for pump and then cranking (until I remembered about the bleed/gauge valve). It don?t take long for it to start sounding weak at cranking.

The reason I ask is that I?m probably going to put a split charge system in over the winter. Either going to keep a proper starting type battery and have a deep cycle leisure battery as no.2.....or perhaps even have two of the batteries that claim to be dual purpose, starting and leisure.
Thoughts on that ? I think I feel that it should be one or the other ?

 

[alldodge]

A true deep cycle may not have enough amp output to crank the motor over if needed, but it can be drained lower without damage. If you use a lot of power floating around on battery, then may be a good idea, but otherwise a dual purpose or two starter bats. Use a Add-a- bat ACR and it will take care of the charging for you

 

[isaacs]

I like to run two marine starting batteries. No dual charging system--get a dual battery switch and alternate batteries every time you go out. That way you can shut both batteries off when the boat sits and always have a fresh "tested" starting battery as a standby if you sit around listening to music for too long.

My problem is that my current boat doesn't have a good space for a second battery.

 

[QBhoy]

I like to run two marine starting batteries. No dual charging system--get a dual battery switch and alternate batteries every time you go out. That way you can shut both batteries off when the boat sits and always have a fresh "tested" starting battery as a standby if you sit around listening to music for too long.

My problem is that my current boat doesn't have a good space for a second battery.

That?s exactly the plan ! I already have the switch fitted, but nothing else. Haha.

 

[QBhoy]

Ok. Here is another battery question. Aimed towards the boat and the jet ski...
With my wee marine CTEK smart charger on low 0.8a maintenance charge....is it really nesessary to disconnect the battery ? Not so worried about the boat, but I know that the ski has sensitive stator and rectifier ?

 

[alldodge]

Don't know
Will say if its a lead acid bat, it won't last that long, 2 to 4 yrs (mine were 2 yrs until switching to AGM)

 

[Lou C]

I've run Deka gp 27 dual purpose batteries with a simple 1,2,both,off switch for years and have had few issues. One thing I can advise is don't trust the dash gauge 100%, check the actual charging voltage at the batts with a digital voltmeter. Should be about 14.2V or so.
I've been getting 5/6 years from these batts. I just make sure when the boat is put in storage they are both fully charged...

 

[QBhoy]

You are dead right Lou. The voltage indicated on my dash voltmeter is a fair bit different from what the smart craft says. Seems to be compromised by load variations.
I?m in two minds about taking the batteries out the boat and ski or just leave them connected and stick the wee charger on every now and then.
Worried about doing this with the ski though. I learned of the electrical sensitivity on these the hard way. Years ago with an old ski I once jump started it from the boat. I blew fuses and rectifier. Doh !
Hopefully the wee 0.8a smart charger wouldn?t damage anything....

 

[achris]

I have 2 marine batteries (N70ZZ) and a simple off/1/2/both battery switch. When the boat is at home I leave the switch on both and put a 150mA charger on to one of the batteries (doesn't matter which). When I head out for the day I simply remove the charger and go. If I'm camping out overnight and have a fridge with me, in the evening I switch to one or other of the batteries. That way I know I have a full fresh one if the fridge draws too much overnight. To date, never flattened a battery to the point it won't kick the engine.

Chris. .....