Jump-starting

[88LX-iSedan]

What should i use for a ground when jumping my car.. i was thinking the engine ground on the valve cover but, wasn't sure if it was wise to do so.

TIA

[NXRacer]

ground it to the battery ground

[Bryan]

Negative on the battery = ground right?

[shepherd79]

you can do use body ground or battery ground.
if you use battery gorund you will charge the battery slowly.
if you use the body ground, you should be able to start the car right away.

[Blkblurr]

Makes no difference as long as you get a good ground contact. The more surface area, the better. I always use the battery ground. All grounds on the car connect to the battery ground. The best contact is usually the battery ground.

[DBMaster]

The reason for connecting the negative cable to a body or engine ground rather than to the negative battery terminal is one of safety. A discharged battery can often give off hydrogen gas. When you make the final connection, there is often a small spark. This runs a small risk of causing an explosion from the ignition of the hydrogen gas in the air around the battery. The risk is pretty small, I think, but why take take it?

Anyway, I have jump started enough cars in my life to give you the order of connection.

1. Positive cable to positive terminal of "good" battery.
2. Other end of positive cable to positive terminal of "bad" battery.
3. Negative cable to negative terminal of "good" battery.
4. Other end of negative cable to body or engine ground on car with "bad" battery.
On my car I have used the spot where the ground wire connects to the valve
cover. Connect as far away from the battery as you can get.

Run the engine on the car with the good battery for about 30 seconds. Start the car with the dead battery and disconnect the cables in the opposite order of that described above. If the car with the dead battery does not start chances are there are more or different problems than the battery.

[88LX-iSedan]

Thanks again.. Just figured it was time to start it up, been sitting for nearly four months now. lmao

[k-roy]

For a ground I used the P/S bracket on the block when I had P/S

[Magny]

ok for one thing, I learned in my auto shop class in HS that to never, ever connect pos. with pos. and neg. with neg.. Its just like taking 2 regular "AA" batteries and doing the same by bridging wires to the contacts, you will blow the batteries and/or fry the cells. The teacher also showed us a video of car batteries exploding while trying to jump start it that way. Always put the neg. to the car that needs the jump to a metal ground, preferably at the alternator bracket. But since our cars are hidden in the back use a metal bar that is on the engine, such location should be where the wire is on the valve cover or some bare metal bracket.

Car #1.............Car #2
Pos. - Neg. / Pos. - Neg. = BAD
Pos. - Neg. / Pos. - Ground = GOOD

[Blkblurr]

Hydrogen build up happens in small concetrations when you are charging a battery for long periods with no air circulation. Connecting to a negative ground away from the battery is for charging only and only when you disconnect the charger cables. The hydrogen isn't present before then. It makes no difference on jumping. There are so many misunderstandings about this that I hear some good stories as to how to jump a car. I have never had a problem doing it the way I've described. If you think about it this way: When you try to start a car where does the current come from? The battery through the cables and to the starter. The positve of course goes through the starter solenoid. Why wouldn't you connect the jumper cables the same way? It won't hurt to connect the negative cable to the frame on the dead car but to only reason to do that is if your negative cable on your battery is bad. The battery cables are made to carry full current to the starter. Where else would the car get power to start?

[Blkblurr]

ok for one thing, I learned in my auto shop class in HS that to never, ever connect pos. with pos. and neg. with neg.. Its just like taking 2 regular "AA" batteries and doing the same by bridging wires to the contacts, you will blow the batteries and/or fry the cells. The teacher also showed us a video of car batteries exploding while trying to jump start it that way. Always put the neg. to the car that needs the jump to a metal ground, preferably at the alternator bracket. But since our cars are hidden in the back use a metal bar that is on the engine, such location should be where the wire is on the valve cover or some bare metal bracket.

Car #1.............Car #2
Pos. - Neg. / Pos. - Neg. = BAD
Pos. - Neg. / Pos. - Ground = GOOD
If you do this you will cause a fire and do alot of damage. Always positive to positive and negative to negative. No if and or buts.

[Magny]

If you do this you will cause a fire and do alot of damage. Always positive to positive and negative to negative. No if and or buts.

LOL hmm, I guess this is gonna be who is right or wrong duel then huh???

Check this out. (http://www.carbuyingtips.com/jumpstart.htm) A how to on jump starting a car.

Here is another. (http://autorepair.about.com/cs/doityourself/a/bljumpstart.htm) Want more???

Here is a good one. (http://www.samarins.com/diagnose/) Scroll all the way down until you get to "Car won't start after jump start". Thats a better detail of another thing that could happen too.

Couldn/t find any video's of the batteries exploding while jump starting, but with those three in mind, you can get the idea never to do it that way. Unless you have something to prove that pos. to pos. and neg. to neg. is a good way of jump starting a car safely, then prove it to me. Other than that if you can't find it, I don't wanna hear another word. I know what I am talking about. If you taken an automotive class like I have, then you should know the right way of jump starting a car safely. If not, read up on it, it will help you in the future.

[Blkblurr]

Magny, Are you saying here to connect the positive to the negative?
Car #1.............Car #2
Pos. - Neg. / Pos. - Neg. = BAD
Pos. - Neg. / Pos. - Ground = GOOD
If so, you are going to have a fire. If you are referring to connecting the dead car negative terminal to the car ground and not the battery it really does not matter. This person that does this a lot in the link you pointed to is suggesting that it's the way he does it. I'm sure it won't matter for the reasons I stated earlier. I simply want to dismiss some ot the misconceptions that come as a result of people not understanding electrical systems. It's not my goal to step on anyone's toes or win at a duel as you said. I have a degree in Electrical Engineering and 22 years of experience designing and building systems that test and manufacture systems for cars including alternator test stands. I have a lot of experience in this area. I may have misunderstood your word diagram when you were showing the cable connections but cool down man. This board is for helping people, not for duels or fights.

[88LX-iSedan]

I will admit, at first glance it was some-what misleading. I'm sure what he is saying is, Using a ground on the car you're jumping is "GOOD" and using the "Neg" terminal is bad. ..not positive to negative

[Blkblurr]

LOL hmm, I guess this is gonna be who is right or wrong duel then huh???

Check this out. (http://www.carbuyingtips.com/jumpstart.htm) A how to on jump starting a car.

Here is another. (http://autorepair.about.com/cs/doityourself/a/bljumpstart.htm) Want more???

Here is a good one. (http://www.samarins.com/diagnose/) Scroll all the way down until you get to "Car won't start after jump start". Thats a better detail of another thing that could happen too.

Couldn/t find any video's of the batteries exploding while jump starting, but with those three in mind, you can get the idea never to do it that way. Unless you have something to prove that pos. to pos. and neg. to neg. is a good way of jump starting a car safely, then prove it to me. Other than that if you can't find it, I don't wanna hear another word. I know what I am talking about. If you taken an automotive class like I have, then you should know the right way of jump starting a car safely. If not, read up on it, it will help you in the future.


Car won't start after jump start

If, for example, you accidentally connect the booster wires from other car to your battery the wrong way ("+" to "-" and "-" to "+" ) whith ignition ON even for a moment, it may burn the engine computer and other electric components. When using jump start be very carefully connecting the cables - never mix polarity.

Isn't this what I said in the bold red print? Why are you wanting me to read this???

[Magny]

ok, now one thing I would like to say is that, yes I am sorry for my diagram being misleading. I shoulda made a drawing of it instead of text. And I also thank 88LX-iSedan for putting it the way it was meant to be said. I'm sorry about all the confusion. Next time, I'll make a drawing besides text, it will help in the end LOL.

[Blkblurr]

ok, now one thing I would like to say is that, yes I am sorry for my diagram being misleading. I shoulda made a drawing of it instead of text. And I also thank 88LX-iSedan for putting it the way it was meant to be said. I'm sorry about all the confusion. Next time, I'll make a drawing besides text, it will help in the end LOL.

No problem. :cheers:

[88LX-iSedan]

Well, i jumped it.. Turned right over with no probs, let it run, shut it off and back on.. all's good. ..Although, i think it turned over a bit too easy. Could this be due to the "bad head gasket"? (Loss of compression) ..Either way, i'm finally replacing it soon. ..oh yeah, and thanks for the help again.

[Blkblurr]

Well, i jumped it.. Turned right over with no probs, let it run, shut it off and back on.. all's good. ..Although, i think it turned over a bit too easy. Could this be due to the "bad head gasket"? (Loss of compression) ..Either way, i'm finally replacing it soon. ..oh yeah, and thanks for the help again.

Loss of compression will cause that.