some quick info on optima's please

[gcurtis]

As a battery distributor I shy away from Optima. I've seen quality severely drop in the past three years and now only recommend the Odyssey line of AGM batteries.

 

[Vince]

We have a 2.8CRD JK Unlimited and it came new from the factory with a yellow top Optima. My XJ has an Odyssey PC1200-MJT, when the Optima dies in the JK I will replace it with an Odyssey.

 

[EMSJEEP]

Yes the yellow top has side posts...mine has been fine for going on 3 years now...

 

[BlueCuda]

I use a yellow top, its been great for a few years now plus two (2) 7-cell blue tops in the trunk for house batteries. Also have a great warranty service, 18 months free replacement, 3 years prorated (for the blues at least).

Bieng an Optima vendor I am curious about these 7 cell Optimas. A battery with 7 cells is a battery with 14 volts...explain. Are you sure you don't mean the group 31 Blue Tops? Very large but still 12 volts with 6 cells.

Just to clarify, There is two blue top marines. The cranking marine is a red top with marine posts and marine warranty. The Deep cycle marine(light greay bottom) is the same as a yellow top but with marine terminals and marine warranty(which is better than a yellow top).

 

[Starscream]

Another good choice to look into: Odyssey PC1200

 

[5-90]

I know some people have melted the side terminals on Redtops overloading them with excessive loads.However, alot of GM vehicles come from the factory with side terminal batteries and battery cable connectors.Would it be safe to use the redtop's side terminals along with the GM battery cables?I have not run into this scenario, but I am curious.Do yellow tops have side terminals as well? I was not aware about the blue top's configuration.

BTW I think optimas carry a 4 or 5 year warranty from the date of purchase. And if you lose your receipt, it goes back to the date of manufacturer. Can't really beat that.

Using a highly intermittent duty cycle for high loads, you can usually get away with the side terminals (GM did for about ten years - the highest load was the starter motor. I don't think GM does that anymore, tho...)

I actually talked to Optima, Exide, and Interstate about that a few years ago, and the common consensus for "constant duty" load was (adjusted downwards slightly by me) 75-80A. More than that, and you'll run the risk of melting the side terminal pads right out of the battery case!

So, you can run some auxiliary lighting, radios, light electronics, inverters, whatever off the side posts without too much trouble, as long as you stay below that figure.

As far as connections go, the side posts accept a 3/8"-16 thread, so just use a short 3/8"-16 screw (1/2" or 5/8") and stack washers on it until you can snug it up, if you don't have enough lugs. Or, you can use the silly GM side terminal post and screw combination, or use the GM side terminal post and a 3/8"-16 screw (either way.) Just don't overtorque the thing - the side terminal is, after all, lead, and it's depressingly easy to pull the threads out...

 

[EMSJEEP]

Bieng an Optima vendor I am curious about these 7 cell Optimas. A battery with 7 cells is a battery with 14 volts...explain. Are you sure you don't mean the group 31 Blue Tops? Very large but still 12 volts with 6 cells.

Just to clarify, There is two blue top marines. The cranking marine is a red top with marine posts and marine warranty. The Deep cycle marine(light greay bottom) is the same as a yellow top but with marine terminals and marine warranty(which is better than a yellow top).

It has 7 round chambers where my yellow top has 6, is there something else in the 7th?

 

[BlueCuda]

You sure its got 7? I am pretty sure they have 6, they are offset to there is a gap on the opposite corners.

 

[jeepme]

Using a highly intermittent duty cycle for high loads, you can usually get away with the side terminals (GM did for about ten years - the highest load was the starter motor. I don't think GM does that anymore, tho...)

I actually talked to Optima, Exide, and Interstate about that a few years ago, and the common consensus for "constant duty" load was (adjusted downwards slightly by me) 75-80A. More than that, and you'll run the risk of melting the side terminal pads right out of the battery case!

So, you can run some auxiliary lighting, radios, light electronics, inverters, whatever off the side posts without too much trouble, as long as you stay below that figure.

As far as connections go, the side posts accept a 3/8"-16 thread, so just use a short 3/8"-16 screw (1/2" or 5/8") and stack washers on it until you can snug it up, if you don't have enough lugs. Or, you can use the silly GM side terminal post and screw combination, or use the GM side terminal post and a 3/8"-16 screw (either way.) Just don't overtorque the thing - the side terminal is, after all, lead, and it's depressingly easy to pull the threads out...

I just picked up a yellow top and the spec sheet says you can run starting duties off of the side posts and starting and eccessories off of the top posts. So I guess its safe to say you could hook up the starter to the side posts, and the winch, commpressor, lighting etc.to the top.

 

[5-90]

I just picked up a yellow top and the spec sheet says you can run starting duties off of the side posts and starting and eccessories off of the top posts. So I guess its safe to say you could hook up the starter to the side posts and the winch, commpressor, lighting etc.to the top.

You can, but you really shouldn't. The side posts have the problem of being at the bottom of a plastic well.

As you may already know, conductors do heat up when they are conducting electricity - the more electricity (current,) the more they heat up. Also, there are issues with using a conductor too small for the current - but we'll leave those aside for the moment.

With top posts, they're out in the open, so it's no trouble to keep air moving about them. Problem solved.

Side posts, as I mentioned, are at the bottom of a plastic "well." Also, they're capped with what is essentially a lead "plate" - the terminal. Lead ain't the best conductor of heat, so that's a bit like putting a lid partway over a pot while it's boiling.

If you just use it for starting loads only, you've got an agreeably low duty cycle (as a comparison of overall life - down around 0.5-1.0%) and the terminal should survive that indefinitely. That's why they say you can use it as a starting terminal - wire everything else up top.

However, you'd actually be better off to do it the other way around - wire the side posts for light accessory duty (which would use copper or tinned copper lugs - better conductors of heat, and smaller - and you're likely to run a lower load on them...) and wire all the heavy stuff up top. This includes charging current - since most of us run alternators somewhere well north of 100A rated output, and have enough electrical accessories to use that current!

That's my argument against side posts in Jeeps - given the electrical loads we tend to use, and the electrical sources we tend to have, the odds are better than even that you'll end up melting the lead pads enough to not hold a screw anymore inside of a year or so, if you use them for "full duty" with side terminal pads on the cables.

I'd probably consider the "ideal" of accessory attachment on side posts to be using an "extension" side post screw (the one that has the piggyback stud for accessories above the standard contact pad,) and use the extension stud to connect the terminals. Then, you've got airspace over the lead pad to work with - assuming it's a fairly standard Pb/Sb alloy they're using (no reason not to - antinomy makes the alloy a little harder and increases the melt point slightly) you're still looking at a MP of about 700*F - which isn't hard to hit if you're pushing over 100A through the thing for any length of time, and you can't get any cooling air over it. Oops.

And, you don't even have to get it hot enough to melt. Lead and lead alloys will usually soften down around 300*F - which is far easier to hit, and will allow a screw to pull out of the thing with minimal force. Oops.

These are the things that don't make it out past the marketing people - which is why I'm persistent about getting to talk to Engineering, instead.

 

[EMSJEEP]

You sure its got 7? I am pretty sure they have 6, they are offset to there is a gap on the opposite corners.

OMG...have I been totally enveloped in my own little delusion for the past 2 days??? I'm affraid to go look now....

 

[Stumpalump]

Optimas can be brought back to life with a trickle charger. 10Amp chargers don't work well. You may think it's charged but only a long slow charge will actually charge them so the charge will hold. http://www.naxja.org/forum/showthread.php?t=922445&highlight=optimas+suck
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[jeepme]

You can, but you really shouldn't. The side posts have the problem of being at the bottom of a plastic well.

As you may already know, conductors do heat up when they are conducting electricity - the more electricity (current,) the more they heat up. Also, there are issues with using a conductor too small for the current - but we'll leave those aside for the moment.

With top posts, they're out in the open, so it's no trouble to keep air moving about them. Problem solved.

Side posts, as I mentioned, are at the bottom of a plastic "well." Also, they're capped with what is essentially a lead "plate" - the terminal. Lead ain't the best conductor of heat, so that's a bit like putting a lid partway over a pot while it's boiling.

If you just use it for starting loads only, you've got an agreeably low duty cycle (as a comparison of overall life - down around 0.5-1.0%) and the terminal should survive that indefinitely. That's why they say you can use it as a starting terminal - wire everything else up top.

However, you'd actually be better off to do it the other way around - wire the side posts for light accessory duty (which would use copper or tinned copper lugs - better conductors of heat, and smaller - and you're likely to run a lower load on them...) and wire all the heavy stuff up top. This includes charging current - since most of us run alternators somewhere well north of 100A rated output, and have enough electrical accessories to use that current!

That's my argument against side posts in Jeeps - given the electrical loads we tend to use, and the electrical sources we tend to have, the odds are better than even that you'll end up melting the lead pads enough to not hold a screw anymore inside of a year or so, if you use them for "full duty" with side terminal pads on the cables.

I'd probably consider the "ideal" of accessory attachment on side posts to be using an "extension" side post screw (the one that has the piggyback stud for accessories above the standard contact pad,) and use the extension stud to connect the terminals. Then, you've got airspace over the lead pad to work with - assuming it's a fairly standard Pb/Sb alloy they're using (no reason not to - antinomy makes the alloy a little harder and increases the melt point slightly) you're still looking at a MP of about 700*F - which isn't hard to hit if you're pushing over 100A through the thing for any length of time, and you can't get any cooling air over it. Oops.

And, you don't even have to get it hot enough to melt. Lead and lead alloys will usually soften down around 300*F - which is far easier to hit, and will allow a screw to pull out of the thing with minimal force. Oops.

These are the things that don't make it out past the marketing people - which is why I'm persistent about getting to talk to Engineering, instead.

I see your point. That sums up my thinking of running low draw accessories off the side posts and heavy draw (starting, winch, commpressor) off the top.
Thanks

 

[four_shot]

great work 5-90...

 

[5-90]

great work 5-90...

A man does what he can. I just figured that, with what I'm trying to do, I might as well start really finding out what's going on with this stuff...

Once I've found out, I write it down - after all, this stuff can be important!

 

[xj4fun]

great work 5-90...

X2