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kgrove
12-02-2014, 05:04 PM
I have one of those store bought jump start units with an integrated tire inflator. I keep it in my truck so that it is always handy should my boat battery not be up to starting. So far I've never had to use it, but have let several other people at the boat ramp borrow it to start their boats.

So here's my question: Anyone have any good ideas on how to build my own jump start unit? The batteries on the store bought contraptions are kind of crappy... weak and seem to go bad relatively quickly, especially when stored in my truck.

One thought I've had is just a standard car battery and a pair of standard jumper cables plus a battery charger for the house to occasionally recharge the battery. It's not quite as convenient as the store bought units as it's not a pre-packaged solution with a carry handle and integrated jumper cables. I suppose I could design some kind of wooden box with a handle to house the battery and at least make it more portable.

Another thought has been to buy an extra boat battery, then every couple months just swap it out with one of the batteries on my boat. If I do that after a full day of use, it would be fully charged and would prevent me from also having to have a battery charger at home.

Let me know if any of you have creative solutions or ideas. I'd be fine with the store bought units if they didn't keep crapping out on me after only a year.

cbryan70
12-02-2014, 08:49 PM
There are plans online for these. I have seem some use a small cooler and rig it up. Have you seen the lithium ion jump starts? Way smaller and suppose to work extremely well.

clrussell
12-02-2014, 09:01 PM
There are plans online for these. I have seem some use a small cooler and rig it up. Have you seen the lithium ion jump starts? Way smaller and suppose to work extremely well.


We bought a few of the lithium ion jump packs at work. Work surprisingly awesome and are very light.. Like a pound and will start a completely dead full size vehicle no problem. Want to say they are around $100 too?

cbryan70
12-02-2014, 09:02 PM
Yup let me know what brand they are I've been waiting for someone with first hand experience

clrussell
12-03-2014, 05:52 AM
Yup let me know what brand they are I've been waiting for someone with first hand experience


Will look today, we ordered one as a joke and it worked so well we have about 10 between everyone at the shop now.

BudmanV24
12-03-2014, 08:24 AM
If you choose the full size car battery route I'd recommend a sealed battery such as an optima to prevent spills. Some of em can be found for a little over $100 on amazon.

mikeg205
12-03-2014, 08:32 AM
There' s bunch on Amazon. A member here bought one to have on his 84 S&S - can't remember the brand but I was surprised how small it was.

clrussell
12-03-2014, 08:40 AM
This is the one we have at work. It gets used more than our huge jump pack anymore.

Hard to tell in the pictures but I'm holding it in the palm of my hand http://tapatalk.imageshack.com/v2/14/12/03/49959a2e0a9654de8848f4e7829c05fe.jpg

Rockman
12-03-2014, 09:02 AM
Damnit, another thing I need to pick up this winter...;)

04 Star Rider
12-03-2014, 09:55 AM
Not sure if this is already a thing or not, but with the new technology, when will auto/marine batteries as we know them go away and be replaced with smaller, lighter lithium batteries? I could see the big bulky batteries giving way to batteries the size of the ones you see in cordless drills.

kgrove
12-03-2014, 10:06 AM
This is the one we have at work. It gets used more than our huge jump pack anymore.

Hard to tell in the pictures but I'm holding it in the palm of my hand http://tapatalk.imageshack.com/v2/14/12/03/49959a2e0a9654de8848f4e7829c05fe.jpg

How long are you finding these hold a charge? Are they particularly temperature sensitive? The practicality of these goes way up if they can sit for a month in a hot car and still be trusted to work. If they need frequent recharging they could be false security. Redundant systems work best for the masses when you don't have to pay attention to them until needed.

BudmanV24
12-03-2014, 11:36 AM
Not sure if this is already a thing or not, but with the new technology, when will auto/marine batteries as we know them go away and be replaced with smaller, lighter lithium batteries? I could see the big bulky batteries giving way to batteries the size of the ones you see in cordless drills.

Porsche has a lithium battery upgrade option for the GT3. I believe it's $2,700. So, until the technology becomes more affordable it may be a while

76S&S
12-03-2014, 12:05 PM
Porsche has a lithium battery upgrade option for the GT3. I believe it's $2,700. So, until the technology becomes more affordable it may be a while

$2,700 from Porsche, $27 from Chevy:D:D

clrussell
12-03-2014, 12:25 PM
How long are you finding these hold a charge? Are they particularly temperature sensitive? The practicality of these goes way up if they can sit for a month in a hot car and still be trusted to work. If they need frequent recharging they could be false security. Redundant systems work best for the masses when you don't have to pay attention to them until needed.


I've only seen that one on the charger probably 5 times in the 8 months we have had it. It sits on the counter inside the shop and gets used at least once a day. It has a little battery life button so you can see how much charge it has. I think they say they are good for 20 jump starts on average size vehicles. It also has a USB port so you could charge your phone off it if need be.

kgrove
12-03-2014, 01:22 PM
I've only seen that one on the charger probably 5 times in the 8 months we have had it. It sits on the counter inside the shop and gets used at least once a day. It has a little battery life button so you can see how much charge it has. I think they say they are good for 20 jump starts on average size vehicles. It also has a USB port so you could charge your phone off it if need be.

I'm less concerned about how many jump starts it can handle between charges and more concerned about how long it can sit there doing nothing then pull off 1-2 jumps. I know some of the earlier rechargeable batteries bled energy at something like 1-2% per day... don't know if these fall in that camp or not. Ideally a good jump starter could sit in my trunk for several months and still work.

I did see this similar to what I was thinking of, though looks WAY more expensive than I was thinking. I'm sure it could be done for less with a cheaper battery, cheaper charger, etc., but any way you cut it, it's going to be 2-3X the initial cost of a store-bought jump starter (got mine for $80 at Costco). It would likely last considerably longer, however. My store-bought unit seems to fail (won't hold a charge) every other year.

http://www.hotrod.com/how-to/interior-electrical/1403-building-a-simple-battery-jumper-box/#__federated=1

clrussell
12-03-2014, 02:46 PM
I'm less concerned about how many jump starts it can handle between charges and more concerned about how long it can sit there doing nothing then pull off 1-2 jumps. I know some of the earlier rechargeable batteries bled energy at something like 1-2% per day... don't know if these fall in that camp or not. Ideally a good jump starter could sit in my trunk for several months and still work.



I did see this similar to what I was thinking of, though looks WAY more expensive than I was thinking. I'm sure it could be done for less with a cheaper battery, cheaper charger, etc., but any way you cut it, it's going to be 2-3X the initial cost of a store-bought jump starter (got mine for $80 at Costco). It would likely last considerably longer, however. My store-bought unit seems to fail (won't hold a charge) every other year.



http://www.hotrod.com/how-to/interior-electrical/1403-building-a-simple-battery-jumper-box/#__federated=1


I'll check with one of the guys at work that uses one at home. Ours doesn't really sit unused much.

I want to say when we first got ours we took it out of the box and jumped something with it without charging it. I think they hold charge very well.

mzimme
12-03-2014, 03:45 PM
This one gets great reviews on amazon...

http://www.amazon.com/PowerAll-PBJS12000R-Rosso-Portable-Starter/dp/B00D42AFS8/ref=sr_1_5?ie=UTF8&qid=1417639500&sr=8-5&keywords=jump+box


Says it can jump a car 20 times on a full charge.

mikeg205
12-03-2014, 10:32 PM
One of our other members Bob Kraft bought this.

http://www.amazon.com/Whistler-WJS3000R-Jump-Portable-Starter/dp/B00HWL4NQM/ref=sr_1_1?ie=UTF8&qid=1417663909&sr=8-1&keywords=jump+and+go

pmikler
12-04-2014, 08:41 AM
By no means a battery expert but I sell orthopaedic power equipment. We released a lithium battery this year for the power and at the home office they had several sitting on a shelf for 6 months to test the drop over time. At 3 months it only lost 3%. i dont recall what 6 months was. This juxtaposed to our NiCad batteries that would loose 3% a day. Not sure what type of batteries where used in the first gen jump boxes... maybe NiMH which is more stable but has a memory. In any event Lithium holds charge for a LOOOONG time.

JimN
12-04-2014, 09:39 AM
This one gets great reviews on amazon...

http://www.amazon.com/PowerAll-PBJS12000R-Rosso-Portable-Starter/dp/B00D42AFS8/ref=sr_1_5?ie=UTF8&qid=1417639500&sr=8-5&keywords=jump+box


Says it can jump a car 20 times on a full charge.

"Compact car jump starter that can jump start your car 20 times on a full charge"

Did you miss "Compact car" in this?

JimN
12-04-2014, 09:41 AM
Not sure if this is already a thing or not, but with the new technology, when will auto/marine batteries as we know them go away and be replaced with smaller, lighter lithium batteries? I could see the big bulky batteries giving way to batteries the size of the ones you see in cordless drills.

You're cranking a small-block car engine, not driving screws. The older-style starters that didn't use gear reduction draw between 150A-350A of current and that's why a little battery won't work. Current does the work, not voltage.

mzimme
12-04-2014, 09:41 AM
"Compact car jump starter that can jump start your car 20 times on a full charge"

Did you miss "Compact car" in this?

I think they're referring to the jump start unit being compact... not to jump start a compact car. lol

93Prostar190
12-04-2014, 09:50 AM
You're cranking a small-block car engine, not driving screws. The older-style starters that didn't use gear reduction draw between 150A-350A of current and that's why a little battery won't work. Current does the work, not voltage.

Hats off sir .... OHM's Law is still alive, brings me back to my engineering roots ...

AMPS baby, AMPS !

Lithium ION has potential ... just ask any Hybrid car engineers ....

thatsmrmastercraft
12-04-2014, 10:12 AM
You're cranking a small-block car engine, not driving screws. The older-style starters that didn't use gear reduction draw between 150A-350A of current and that's why a little battery won't work. Current does the work, not voltage.

Hats off sir .... OHM's Law is still alive, brings me back to my engineering roots ...

AMPS baby, AMPS !

Lithium ION has potential ... just ask any Hybrid car engineers ....

Thanks you gentlemen. I was afraid everyone was going to fall into the "shiny trinket" trap.

JimN
12-04-2014, 10:22 AM
I think they're referring to the jump start unit being compact... not to jump start a compact car. lol

Ever touched the clamps after cranking a 5.7L engine? I don't recommend it. The voltage drop caused by cranking means it's drawing a lot of current and the chart shows 400A, but it also shows only 12,000 mAh as the capacity. That's 12 hours @1A, 1 [email protected] and at 400A, it's a total of 108 seconds, but it doesn't specify how far the voltage will drop before it's no longer within the window for usefulness. It cold very well mean that voltage is still measurable but that doesn't mean it's useful. The chart also shows "20+ starts on full charge, so.....

I hope it comes with instructions for maximum crank time because cranking for too long can make these dangerous and with a stone dead cranking battery, it will take some time to get it to crank at full speed.

http://g-ec2.images-amazon.com/images/G/01/automotive/detail-page/B00D42AFS8-5.jpg

JimN
12-04-2014, 10:24 AM
Hats off sir .... OHM's Law is still alive, brings me back to my engineering roots ...

AMPS baby, AMPS !

Lithium ION has potential ... just ask any Hybrid car engineers ....

"LiION has potential"? That's hilarious!

JimN
12-04-2014, 10:28 AM
Thanks you gentlemen. I was afraid everyone was going to fall into the "shiny trinket" trap.

Like movies, where they take a jump start pack and torture someone, complete with massive sparks, screaming and melting skin?

93Prostar190
12-04-2014, 10:29 AM
"LiION has potential"? That's hilarious!

I knew you would catch that one ....

Happy Holidays!

thatsmrmastercraft
12-04-2014, 10:53 AM
Like movies, where they take a jump start pack and torture someone, complete with massive sparks, screaming and melting skin?

Exactly. http://www.7thgenhonda.com/forum/images/smilies/smiley-rofl.gif

gsxrjtt
12-04-2014, 11:02 AM
SO bottom is that POD unit actually decent for starting boats with flat dead batteries ???

Bouyhead
12-04-2014, 12:49 PM
I bought the Allstart jump start from a speciality tool guy. He had tried a few differant brands but liked this one the best. Said it started a stone cold v8 diesel.

120548

clrussell
12-04-2014, 01:53 PM
They got me one for diesel trucks today. We shall see how it does.. http://tapatalk.imageshack.com/v2/14/12/04/c72971aff07e47613f4e083f26e82e16.jpg
http://tapatalk.imageshack.com/v2/14/12/04/80602158781a2b6dcc02e54b8c2f8b03.jpg

thatsmrmastercraft
12-04-2014, 02:30 PM
They got me one for diesel trucks today. We shall see how it does.. http://tapatalk.imageshack.com/v2/14/12/04/c72971aff07e47613f4e083f26e82e16.jpg
http://tapatalk.imageshack.com/v2/14/12/04/80602158781a2b6dcc02e54b8c2f8b03.jpg

I was going to say to leave the truck out overnight with the headlights on, but only going down to 43 won't give that much of a test.

clrussell
12-04-2014, 02:57 PM
I'll be testing it first chance I get. I usually use a roll around battery charger..

clrussell
12-04-2014, 03:01 PM
Just read the instructions on this one. Days will hold charge 3/6 months but is recommended recharge every 3 months.

Can be charged off of 12v cig lighter plug too.

h_2_o
12-04-2014, 10:28 PM
one thing to consider or have in mind with the Lithium batteries is their lets say "stability". I've had to make connections on many Lithium based batteries and to do it correctly (imho) you really need a spot weld on there. Soldering gives it to much heat (can be done but please dont try it) and i've seen packs go and it is not a pretty sight. What am i getting at with this is I am not sure i would suggest to anyone to make a pack like this for their boat considering the amount of bouncing and general non-smooth ride the a boat has and the increased potential for an explosion.

bsloop
12-05-2014, 02:46 PM
I recently dis-assembled an old Husky combo jump pack that was dead.
It basically had a sealed 19AH motorcycle/jet ski battery. This explains why it has some pep but may not crank over an old, cold big block. Especially a marine engine whose starter is likely compromised due to corrosion.

If weight is a concern, one of those batteries with 300cca runs about $60. If CCA is more important, I just picked up a full size 800cca Interstate MTP-24F for $90 after rebate.
Jump pack may get you out of a weak battery bind on the water but should not be your only "arrow in the quiver" if you are the prepared type.

I bought this pair of 25' heavy jumper cables last spring. They got used several times a month, especially once word got out on the party line. 25' is awesome to reach two boats away and down into a cruiser bilge, between two slips or at the launch ramp.
http://www.amazon.com/gp/product/B0030CVH2K/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

east tx skier
07-23-2015, 12:23 AM
I'll revive this thread.

I got a Powerall Lithium Ion Jump Starter for Christmas. Nothing huge. 200--400 amps. I charged it up on Christmas day and tossed it in the trunk of my car, where it sat for nearly 7 months without any recharges and suffering through up to 100 degree temps for the last several weeks.

Today, before going to the lake, I did a Perfect Pass upgrade, and noticed that the display was acting funny (typical when there is a low battery). I took my big jump starter of power and also grabbed the little on out of the trunk of my car.

When we got to the lake, as I suspected, the boat battery was on life support and the boat wouldn't crank. I tried the big one first and got nothing. I popped the not charged in 7 months little jump starter on there and while the boat didn't spring to life, it turned over and started.

My ski partner was most impressed that something so small could pack enough punch to save the day. I'm charging it and have added the 600 amp version to my wish list.