Golf cart batteries for the starting battery

[anm]

I've been wondering, is there any reason I couldn't replace my starting battery with say two t105s? And use the one battery for everything? I know I'd have to be careful not to run it too low since it would be nice to be able to start the van, but is there any other reason not to?

 

[blars]

True deep-cycle batteries, such as golf cart ones, are not designed for the short high current of starting an engine. They should work as such when fully charged and at warm temeratures. Marine batteries are a compromise, and not great at either.

 

[SternWake]

A pair of t 105's, when healthy and fully charged, will have somewhere between 800 and 1150 CCA, which is more than enough to start most engines.

Can you fit a pair of t105's where the engine battery goes?

They are much taller than a regular battery.

I am not sure how well a pair of depleted t105's would crank the engine.
I have a Northstar group 27 AGM which starts my engine easily when it is depleted down to 30%, but my deep cycle flooded group 31 battery depleted to 50% turns the engine slowly, and my engine always starts very easily. So this leads me to believe that a discharged flooded deep cycle battery struggles to provide enough current to crank a starter motor.

But my flooded 31 weighs 64 LBS(620CCA), your paired t105s are basically double that amount of lead.

A group 31 battery Size was originally designed as a starting battery to achieve in excess of 1000 CCA. When Deep cycle internals are stuffed into this starting battery jar, there is not a good electrolyte to lead ratio and the battery needs a rather intense recharge regimen with high voltages and durations to reach full charge, and these parameters actually are hard on the battery.

T-105s and golf cart batteries were designed around deep cycling duties, and no compromises were made in achieving this, and they do not need as much loving to get back to full charge.

But while they were not designed to start engines, they certainly can. I would just be leery of doing so if they are drained below 50%, as the high current required might knock the sulfate off the plates where it drops to the bottom of the cell, where as if it were recharged it would be redissolved into the electrolyte.

Not sure about that last sentence. Just a hypothesis.

 

[akrvbob]

I almost always switch to Marine batteries as my starting batteries, but I wouldn't use golf carts.
Bob

 

[TucsonAZ]

Yeah, different kind of battery with different plates inside, you can use either for the other but it will be to the detriment of the battery.