I'm looking to buy a battery jumper pack. Anyone have any experience with these on 300D's? Any recommendations on brand or cranking amps would be great-Thanks!

I have one of these. 400 cranking amps, 900 peak amps. It jumpstarted my 300D when the battery crapped out, and it has an air compressor and flashlight built in. They're cheap and in the year or so I've had mine, it's served me well

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since diesels require more amps to kick over the engine than gas engines do...two borrowed battery packs failed to wake up my 240D when the battery died...in warm weather.

Car also wouldn't start when hooked up to a AAA service car with cables, just because amps were just enough to tickle a gas engine back to life.

The important thing with these jump starters (and jumping our diesels from non-diesel cars as mentioned in another ongoing thread) is to hook them up and give them a while to charge up your battery before trying to start it. No way will the jump starter be able to do it on its own.

I bought a couple off eBay from Toolamerica recently (they've still got more on there, here). Unfortunately they sent me the wrong ones (only 300CA and 700 peak amps, whereas the specs were supposed to be the same as speedy300Dturbo's). I complained to their sales rep and she's shipping me two more of the right ones, plus I get to keep the first two free since it isn't worth their cost to ship them back .

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'81 300TD Wagon 355k (Miss Diesel)
'83 300SD 180k
'84 500SEL 190k (Parting it out)

As I posted before, I used a portable jump box on my '87 300D that was sitting for 5 months and it started right up after only about 5 seconds glowing and another 5 seconds cranking. It's a Solar ES 5000 model.

If you need to let it charge the battery for 5-10 minutes before it will start as some have said, then the jumper cables or battery cables are bad or you have a bad connection. You should even be able to start the car with the battery removed and just the jumpers attached to the battery cables.

The suggestion to hook up a jump box and give it a while to charge up your battery before trying to start it is wrong. When you hook up the jump box to a bad battery, the bad battery will draw away the current from the jump box so that after 10 minutes you won't be able to start anything. The jump box will have the most power right when you attach it. Connect the jump box, glow, and start as fast as possible.

That's what the instructions that came with my portable jumpstarter specifically said to do. I imagine this is because while the jumpstarter has plenty of power, it cannot put it out fast enough in the amounts needed to start our cars (300 or 400 cranking amps just isn't enough). Allowing some of the power to transfer over to the dead battery for a few minutes (assuming it is in rechargable condition and has not gone completely kaput) lets both batteries assist in starting the car.

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'81 300TD Wagon 355k (Miss Diesel)
'83 300SD 180k
'84 500SEL 190k (Parting it out)