Jump starting: conflicting advice

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Sat 11 Feb 2006 08:46
Jump starting: conflicting advice - Roger Jones
I needed to jump start one of my cars yesterday. Having not done that for years, I thought it would be sensible to check for the correct procedure. Two online sources told me:

1. positive to positive
2. negative to bare metal on the target engine ("NEVER to the negative terminal, as this can ignite and cause both batteries to explode." "DO NOT hook it to the battery negative terminal as there maybe hydrogen gas present from the battery and a spark from the connection could cause an explosion.")
3. start the source engine

A general household manual says:

1. start the source engine
2. negative to negative
3. positive to positive.

The manual for the Mercedes involved said:

1. positive to positive
2. start the source engine
3. negative to negative.

Naturally, I followed the MB advice, but why the difference?
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Sat 11 Feb 2006 09:14
Jump starting: conflicting advice - Peter D
Never connect the target battery with the source engine running. Always connect them up and leave for 2 or three mins to allow the initial currnt flow to settle. It the target battery was really flat then start the source and run at 1500 to 2000 rpm for 2 mins then turn OFF and start the target. If you want to keep your alterator diode pack and your ECU that is what you do, Regards Peter
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Sat 11 Feb 2006 09:17
Jump starting: conflicting advice - Omegaman
Personally I don't think any of these are particularly dangerous/right or wrong - hydrogen is a pretty light gas and is dispersed quickly from the vicinity of the battery;- you're unlikely ever to have enough hydrogen present to cause a significant explosion that would cause you injury or ignite anything under the bonnet.
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Sat 11 Feb 2006 09:25
Jump starting: conflicting advice - henry k
Quick reply.
Search the forum for previous items.
There are also risks when taking leads OFF like needing to switch ON HRW first.
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Sat 11 Feb 2006 09:36
Jump starting: conflicting advice - Roger Jones
There are many dozens of previous posts on the topic, most of which add to the confusion. I'm just surprised that advice varies so much on such a basic procedure, hence the question as to why it does.
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Sat 11 Feb 2006 09:37
Jump starting: conflicting advice - martint123
The last connection and first DIS-connection should be to the bodywork (chassis, engine whatever)- not a battery terminal.
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Sat 11 Feb 2006 09:51
Jump starting: conflicting advice - jc2
Why???
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Sat 11 Feb 2006 09:57
Jump starting: conflicting advice - Aretas
If you connect chassis to chassis first, then when you connect other lead to the positive terminal of one of the batteries there is a distinct possibility of you brushing the other end against a piece of chassis when reaching to the other positive terminal.

So my way is pos to pos first, then neg to neg.
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Sat 11 Feb 2006 10:22
Jump starting: conflicting advice - Roger Jones
What is a "DIS-connection"?
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Sat 11 Feb 2006 10:35
Jump starting: conflicting advice - bell boy
very bad advice,never ever underestimate the sulphation off a battery .




--
\"a little man in a big world/\"
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