Jump Start Packs

[2iar]

Hi Ausfishers,

Does anyone have any advice on the following. Here's the background:

1. I've got a Heavy Duty Jump Start Pack. It's probably about 3 years old, and I think the sealed battery *may* be on the way out. It's supposedly "1200 Amp" (though I don't know the CCA's)

2. I fully charged the pack, and had a go at starting my Suzuki DF70 from it (not jumping ie the main was diconnected), and it just doesn't seem to have the required oomph.

3. The manual says the outboard requires a 500 Cold Cranking Amps battery - my main battery has 650CCA.

4. I tried starting the motor off a cheap $40 car battery. I'm sure this would only have 300CCA's max, and probably less. It worked no problem.

So, is it more likely that the jump start pack battery is dying (the guage shows it to be 100% charged before starting the exercise), or is this pack not big enough in the first place? It's the most expensive one from SC Auto, and I bought it originally for the 4WD. I've just no way of knowing how to convert this "1200 amp" to CCA's...

Either way, it doesn't seem that this particular pack is any good on the boat - I'd like to know if I buy a new battery for it, whether it will be able to kick the engine over in the event that the marine battery fails, or whether I just take the $40 one out for insurance.

Thanks for any advice,
Mike

[krazyfisher]

at a guess 1200amps could be 400cca. I just bought one that is 1500 amps and 500cca. 3yrs is not a bad life out of a battery it could be on its way out even though it tells you that it is full. some of these packs do state that they will not start a dead flat battery.

[trilogy]

2iar
If the jump starter worth saving ,drop it in to a battery specialist shop and have the battery tested under load,this will tell if the battery is correctly holding a charge or not. If the battery is at at fault Stupid Cheap Auto have replacments for about $40 the amazing thing is they are just the batteries that back up alarm systems.Or after 3 years it could be time for a new one.

Regards
Adrian

[al-straddie]

cheaper just to take your spare with you But if youv'e got room for it, wire in a dual battery set up.

brings plenty of peace of mind, knowing you've always got starting power.........now if only I'd changed the spark plugs......

[2iar]

2iar
If the jump starter worth saving ,drop it in to a battery specialist shop and have the battery tested under load,this will tell if the battery is correctly holding a charge or not. If the battery is at at fault Stupid Cheap Auto have replacments for about $40 the amazing thing is they are just the batteries that back up alarm systems.Or after 3 years it could be time for a new one.

Regards
Adrian

Thanks Adrian (and everyone else who has replied),

A replacement battery is $99, since it was the biggest one they carry. That's really my issue: I like the packs as they're useful for camping and running lights and generally handy to have. However, if they're no good for jump startting, I'd be better off with a cheap car battery for backup and would be better off putting the money towards a dual system on the boat...

I also had a closer look at the pack, and it's only 2 years old. If it is faulty, $129 every couple of years doesn't represent decent value for money IMO.

Good luck,
Mike

[2iar]

at a guess 1200amps could be 400cca. I just bought one that is 1500 amps and 500cca. 3yrs is not a bad life out of a battery it could be on its way out even though it tells you that it is full. some of these packs do state that they will not start a dead flat battery.

Thanks mate,

Can anyone confirm the CCA's for sure? This would immediately indicate whether it's useful for the boat or not. Has anyone tried starting their motor for one of these packs (ie not jump starting, I'm looking to worse case scenario and a completely dead primary battery)?

I didn't know about them not starting a dead flat battery, perhaps that's the case?

Good luck,
Mike

[krazyfisher]

you would be lucky to start a dead flat battery on a 70 with anything under a 500cca jump starter. I would be thinking that two years is about all you would get out of a battery.
I will be setting up dual batteries sometime this week but I will still keep a jump starter pack for camping and for just in case

[bidkev]

Mike, I don't know too much about 'em but I've got the el cheapo (49bucks) jumper.

I know it's rated less than 1200 but I can't remember exactly what. Never had need to use it in anger until the other day. It's about 18months old and has been used for running lights when camping. I haven't recharged it for over 2 months and last week it jumped a completely dead battery on the Prado no worries.

As for batteries only lasting 2 years, The better ones come with a 2 year warranty. The one on Kingtin was 31/2 yrs old and still working fine when I sold it.

For peace of mind, I'd go the dual battery system if poss.

kev

A rich person is not the one who has the most, but the one who needs the least.

[Oldyella]

You need to keep those jumpers charged and don't let them run down too much.
A friend had a flat battery in a 6 cyl car and tried to jump it.. but the 600 amp jumper had been sitting for months and was near flat. He charged it up fully and it wouldn't even rotate the motor 1 rev. I think that they deteriorate if left flat for too long.

[Alan_L]

Number 1 rule with lead acid batteries. Do not let them sit in a discharged state. Here's why.

All lead acid batteries will begin to "sulphate" at approx 1/2 charge. This is small sulphate crystals begin to form on the plates, lowering the battery rating. The deeper the battery becomes discharged the more crystals form, eventually covering the plate. Once the battery is fully discharged the plates are completely covered rendering the battery unusable. If the battery was in good condition a slow charge (do not fast charge) will often bring the battery back to a usable condition. If the battery had been discharged for a long period of time, the suphate crystals will start to harden, making it very difficult and in most cases impossible to completely remove them with standard charging. Any sulphate crystals that are left on the plates after charging will reduce the battery output.

You can keep a fully charged battery for approx 3 months without recharging, providing it is in good condition. (Good condition means no lost material from the plates due to overcharging, vibration)

[Dignity]

Mike, took this issue up with my battery supplier - he also sold these things - his basic philosophy was take alook at the size of the battery you currently use, put one of these jump start packs besdie it - obviously it wont have the same punch. Bought a spare HD battery instead and added on the extras myself, much cheaper. The batteries used in these are not meant for any real sustained work.


PS: you around for a drink friday night.

Sam

[2iar]

Thanks Sam,

It kind of makes sense, but that's what they're marketed for. I guess I didn't know that they couldn't start a motor (ie only jumping a low main battery), but knowing the CCA's would help determine this from the start. It's a pity, because its' size on a small boat was the biggest attraction (it fitted nicely in the shelf above the cabin bunks as I didn't want to add any more weight to the back).

I've made a compromise between your setup and what I had, but nothing wired: I've taken the $40 battery, fully charged it, and picked up one of those fancy battery boxes with the external terminals, 12v socket, trip switch and test light for a real bargain $45 (Active Fabrications in Beenleigh). So I've now got more grunt in the backup than I had before for less than the cost of a replacement battery for the pack. The only downside is that it doesn't fit as well, and has to be jammed in the shelf at a bit of an angle. I'm hoping this won't cause any grief.

I'll save up for a dual battery system one day, but this should do in the meantime.

I've emailed you re. drinks...

Good luck,
Mike