I'm thinking about buying a jumper battery to take on a long trip. I'm
not worried about anything in particular but thought it might be good to
have one.

The descriptions I see on line seem more concerned with "bells and whistles" than with cranking power.

Any suggestions or ways to evaluate booster batteries will be appreciated.

I've had two of them. The differences were in the quality of the wire that connected the tiny little wheelchair battery to the clamps, and the way to recharge the pack. My good one is on its third battery (easy to change out) in 11 years and plugs in using a plain extension cord. In other words, i don't worry about losing a charging adapter.

If you can get a good one that needs a new battery, you can save a fair amount of money.

I bought one at a thrift store for $15, but too much because the sealed battery wouldn't hold a charge, so had to buy another for ~$20 on ebay and solder because different connectors. I later saw the same one (different brand names, same factory) new for ~$50. Both plastic clamp jaws cracked and they carry the spring load, so I had to rig other all-metal clamps. I have tested it on my 2.4L 4 cyl engine when its battery went low and it did start the engine. I haven't tried to see if it has the umph to start a diesel. Probably not directly, but if your car's battery can still hold some charge, leave it on for a few minutes and it might transfer enough charge for a few tries.

Better monitoring your car's battery is another option. I have a Battery Brain on all my vehicles, which trips off if the voltage gets too low (not while driving), leaving enough to hopefully start the engine. But, not made anymore. They have helped me identify a failing battery before I reached a no-start condition. I bought 3 or 4 new batteries at Autozone ~2 yrs ago, all gold warranty, and I recall all sooned failed (wouldn't hold a charge), one within 3 months. In all, the Battery Brain started tripping off overnight. I tested w/ my charger, which said "full charge" too fast. Autozone tested on their loader and said "bad", so free replacement. I put an H8 in both my 300D's, but don't recall those failing.

Another monitor is a cigar lighter voltmeter on all trips to insure the alternator is active. I don't like surprise "won't start" when I stop mid-travel.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans

The most direct route is to buy a good 20 AH ( Amp Hour ) sealed lead acid battery and hook some short thick gauge jumpers directly to it. Look at electronic parts sellers like Digi-Key , Allied, Farnell , Arrow. Use a small automatic charger to charge it.

You could even wire it to the car using a blocking diode, this way the car will charge it but the car can't discharge it. When you need it, unplug from car then use the jumpers to start the car.

A sealed lead acid battery can be mounted in any position and not leak though they will leak if overcharged while mounted upside down. There really isn't any reason to mount upside down anyway.

Battery jump packs have been brought many times over the years.
There has been a lot of pro and con results an answers.
If you have a stone cold Diesel, then you will need a large enough one to kick it over.
remember, the battery will be drawing power from it if it is down on juice and the GP`s are drawing power also.
So will poop it out quickly.

I have had a Diesel since 81, whether my 81 Datsun Diesel PU, the 240D or 300D, If it is dead, you will have
to have the cables hooked for quite a while to get enough juice in the battery to get it to start.

Here is a few threads I found, happy reading till some of the currant experts jump in.

A lot of the posters are no longer around though, some are.


Battery Jumper Pack

http://www.peachparts.com/shopforum/open-discussion/253054-battery-jump-box-recommendation.html

Portable jump start, 300 amp enough?

With dead battery can't jump, why?

Booster packs for diesel engines

The science of jump starting a diesel


Charlie


sent from my pos computer

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Anyone thought of running a second battery? I know that some of the Pajero 4x4s had a secondary battery on board in case there was ever a starting issue - both batteries would be charged but only 1 used for day to day power/starting the engine.

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UK spec Mercedes W210 E300 Turbodiesel wagon - OM606.962 with 722.6 transmission - rust free!

Jump battery varies a lot in quality and price. The battery they used are normally 17AH to 22AH in a compact jump battery. Cheap one uses 17AH or less. I would try to find a name brand with internal charging circuit so you won't lose the external charger. I replaced the internal battery with 22AH one and it can jump start a stone cold diesel without problem.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

I still like the 1200 from wallmart... still 99.00 everybody else sells it for 129... so...

but I like the 800 amp one from northern tools... around 165 *(it's 120ish with no battery and the battery is 20ish...) the beauty of it is STEEL clamps, very high grade, and a replaceable batter easily changed. I like the light, and the air compressor, and the inverter both have...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Try here. At work we use hundreds of the BB brand per year. Every few months we bake, freeze, over charge, fully discharge a few samples to make sure the quality stays up, so far they have been great. Life span in normal operation is a min of 10 years.

A sealed lead acid works great in a lawn tractor too.

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