Batts questions

The winter killed one of my house batteries.* Port engine wouldn't start, Starboard started right up.* After much testing, port battery isn't cutting it even though it was on a float charge all winter.* Go down to the E/R, flip the switch over to the other batt, and the Port engine fires right up.

My conclusion is the port battery is bad.* I checked the connection, loosed it, cleaned etc to make sure it just wasn't a loose connection.* Tested them separately in different ways and I'm pretty sure the bat is gone, and probably 8 years old or more

So I bought a replacement, but it won't be exactly the same as the batt on the other side.

Question:* If the batt on one side is rated at X:Amps and other side at Y:Amps, then is it OK to run them in parallel as your house system ?* In theory, one batt will be stronger than the other and running in the*1+2 switch mode might tend to make the weaker, older battery draw down the new battery.

Since they are both probably old, I'm thinking I should have just gone ahead and replaced both at the same time.* BTW, they are*plain old flooded bats.

Thanks

Woody

Woody:

I have been told (by the guys at Inlet Marine, who have an interest in selling) that you shouldn't mix old and new on the same circuit, for the reasons you stated. You likely have only a little life left after 8 years, so a pair of new is only going to cost you that remaining few months in the working battery.

An eight year old flooded cell battery is well past its expected life. Replace it. Match the other one you bought.

I should follow the rule of twins, which is replace everything in twos whether the other side needs it or not.

I don't regret it, but my next boat will be a single!* After I learn to drive (pilot?)*this one.

The new battery will discharge into the old battery, shortening its life.* As others have said, replace the other.* Unequal size doesn't matter, but unequal age does with wet cells.

Egregious wrote:

*

The winter killed one of my house batteries.* Port engine wouldn't start, Starboard started right up.

Click to expand...

I agree, replace both, but I question if you really mean that the start batteries double as the house batts?* If that's true, you run the real risk of being stuck somewhere when the overnight house load kills the batts.* You might consider a separate house bank.........Arctic Traveller

*

(Comment irrelevant.* Didn't read the OP post well enough.)


-- Edited by markpierce on Monday 14th of March 2011 01:45:23 AM

Same type, same age batteries and you, your batteries, and your boat will be much happier.

Just curious...
I'm looking to replace the GC-2 golf cart 6v batts on my boat.
Found them at Advance Auto for $100 each (and I have coupons which would drop the price even lower, to about $75)
Also found Interstate for $130 each.
Any suggestions on whether the Interstate is a better battery than the generic Advance Auto?
Or, any suggestions on best brand?

How much do the batteries weigh?* More lead is better.* Are any made domestically?* Warranties?

Most batts in the US are made by only 2 or 3 companies.

Check the warentee and if you will be cruising , decide if trips to Sears or Sams Club would be easier than to the auto supply.