Thanks to everybody for the help.

I do want to Ask one thing about the Volkswagen Jetta Battery Terminals?

You Say they put them in the Driver Side Door to be Safe.

But I was always Told that when put the Jumper Cables on the Car with the Dead Battery the Negative Cable goes to the Body of the Car.

So why do they want you to put both Jumper Cables to the Volkswagen Jetta Battery Terminals in the Driver Side of the Door?

 

I believe that is to store the cables when they are not in use. To use them they must be removed from the driver's door compartment. Also, I recommend storing them in some sort of pouch, box, or bag to protect them from damage to the insulation or damage to the end clamps. And to protect them from corrosion.

But now I see that the VW folks have decided to put the terminals for jumping in a position that will demand that the door on the traffic side be held open. I would count this as one more reason to never even consider owning a VW. Of course, probably they have the battery mounted in some location that takes seven different tools to access. Some auto makers do things like that.

 

You Say they put them in the Driver Side Door to be Safe.

The reason it's safer is that any sparks generated while connecting the cables would be away from the battery and, therefore, not likely to ignite any hydrogen present near the battery.

So why do they want you to put both Jumper Cables to the Volkswagen Jetta Battery Terminals in the Driver Side of the Door?

If the vehicle is the typical negative ground, you'll find that the negative terminal is connected to the body.

 

Is there actually a serious hazard of igniting hydrogen near a discharged battery?? I have done dozens of jump starts over the years, always connecting to the battery posts, and never had a problem. I have also come across melted jumper cables in the snow of a parking lot, which looked like they had been connected wrong, plus to negative and negative to positive. Some times it is difficult to see those markings, and a lot of folks have no clues about polarity.

 

Is there actually a serious hazard of igniting hydrogen near a discharged battery?? I have done dozens of jump starts over the years, always connecting to the battery posts, and never had a problem. I have also come across melted jumper cables in the snow of a parking lot, which looked like they had been connected wrong, plus to negative and negative to positive. Some times it is difficult to see those markings, and a lot of folks have no clues about polarity.

With today's batteries I doubt it but won't rule it out. Back around 1966 I put the electrolyte in and fully charged a new car battery. With the cells still bubbling hydrogen gas I made a fools mistake. I connected negative and while connecting positive bumped chassis. A spark over the top and a heck of a kaboom. I was lucky to retain my sight and a friend washed me down post haste. The bummer was I knew better. I bought that battery out of my next paycheck. Today's batteries have less venting so I doubt they would give an explosion like I experienced but I won't be the one to tempt fate either.

Ron

 

I connected negative and while connecting positive bumped chassis.

Always disconnect Neg first, on Reconnect, Neg Last!

 

Always disconnect Neg first, on Reconnect, Neg Last!

Absolutely and the irony was I knew that in 1966, I just didn't bother to do it the right way. It was amazing I came away with my sight and parts of the battery top slammed into the hood of the car just missing my face. Fortunately with the fiberglass like stuff on the underside of the hood I didn't dent the hood. To this day I remember it was a white 1963 Chevy Impala. Hell, I was 16 working in the gas station part time.

Ron

 

Let me Tell you every step.

When anybody Jumps my Sisters Car they use the 2. Terminals on the Inside of the Driver Side Door.

They do not Store the Cables here this is what I should have Told you.

But I always was Told never put the 2. Cables to the Battery Terminals.

The Positive Cable goes to the Positive Battery Terminal and the Negative Cable goes to the Engine Block.

And they Say this because if the Car Battery gives Off any Gas the Car can Explode when you Jump it.

So always put the Negative Cable to the Engine Block..

But everybody puts the 2. Cables to the 2. Terminals on the Inside of the Driver Side Door on my Sisters Car.

Am I not getting this is this not very Un Safe?

 

If the car is stopped along side a busy road it does not seem that it would be safe. And as I am not at all familiar with the VW terminals arrangement by the driver's door I have no image in mind of how it works. It is just totally different from what I am familiar with.

When connecting cables I connect the negatives first and then the positive of the car needing boosting. Then I connect to the power source car positive terminal, as that battery is not charging and thus no spark hazard, although certainly there will be a bit of a spark. And certainly, at all times, it is vital to focus on the task and not randomly bump things with the connection clamp. Dumb moves because of lack of attention will certainly lead to problems.

 

I always was Told never put the 2. Cables to the Battery Terminals.
The Positive Cable goes to the Positive Battery Terminal and the Negative Cable goes to the Engine Block.
So always put the Negative Cable to the Engine Block..
But everybody puts the 2. Cables to the 2. Terminals on the Inside of the Driver Side Door on my Sisters Car.
Am I not getting this is this not very Un Safe?

Your are a bit mistaken when you say clip to engine block. The old rule was to make final connection by grounding (black cable) anywhere other then directly on the lug of the battery for the simple reason that completing the circuit could cause a spark and being directly on the battery is too close to the possible ignitable gases coming off it. The terminals on your sisters VW are both well away from the battery so there is no danger in any sparks igniting the gases from the battery.

 

I am still wondering about what conditions in a vehicle with a very weak or even a dead battery will lead to an explosive accumulation of hydrogen gas present above a battery. Hydrogen gas is lighter than air and so it does not seem like it would settle on top of the battery. Especially in an outside setting with the hood open that is rather hard to imagine. Possibly with a battery that has screw-on individual caps open, but not in a current battery that has those pressure release multi-cell vents. And what sort of activity would cause hydrogen to be generated, if the battery is not being charged?

 

They started making Sealed Lead Acid SLA batteries years ago just to eliminate that problem. There are still "open" screw cap batteries around, so the idea is better safe than sorry and treat all lead acid batteries as if they were not sealed.

 

They started making Sealed Lead Acid SLA batteries years ago just to eliminate that problem. There are still "open" screw cap batteries around, so the idea is better safe than sorry and treat all lead acid batteries as if they were not sealed.

The difference in appearance between unsealed battery and a sealed battery is quite obvious. And even those whose capped cells can be opened have a complex baffle pressure-release arrangement.
AND we are not, I don't think, even discussing the SLA gell cell battery types. Those are very seldom found in passenger cars. The flooded cell battery type will tend to generate hydrogen when charging, but those types also have pressure release venting that will really reduce the danger of igniting accumulations of the lighter than air gas.
In addition, all of the car batteries that I have ever seen have the terminals a few inches away from the cap area.
So really, the main safety precaution will be to connect the positive cable to the supply vehicle last, and then disconnect it first, after the charged vehicle has started. That puts the spark many feet away from the boosted battery.
Of course caution is till needed for the big battery arrangements on the semi-trucks that have 24 volt systems with four individual batteries. But folks jump-starting them generally know what they are doing.

 

So if I am Looking at these Videos Right when they put a new Battery in and put the Back and Red Cables on the Battery Terminals they do this.

The Ends of the Cables have Ring Type this that Hold the Cable to the Battery Terminals.

Then they put a Bolt on the Side of the Ring that is Open.
Then they put a Nut to Hold it Closed?

Do I have it Right?

 

Then they put a Bolt on the Side of the Ring that is Open.
Then they put a Nut to Hold it Closed?

On an older top mount terminals a nut and bolt were used. Side mount batteries only use a bolt, there is no nut, the battery is threaded to accept the bolt. The bolt or stud may be a long or short version. A Google of automotive battery terminal images will bring up dozens of images for just about every type battery connector / adapter you can imagine.

Ron

 

So if I am Looking at these Videos Right when they put a new Battery in and put the Back and Red Cables on the Battery Terminals they do this.

The Ends of the Cables have Ring Type this that Hold the Cable to the Battery Terminals.

Then they put a Bolt on the Side of the Ring that is Open.
Then they put a Nut to Hold it Closed?

Do I have it Right?

For a battery with posts that is correct. And when you install the battery, remember to connect the non-grounded terminal first, so that if your wrench accidentally touches something grounded there will be no sparks. Then connect the grounded terminal second, and if your wrench touches something grounded, once again, no sparks.
When removing a battery disconnect thegrounded terminal first, then the non-grounded, the same logic applies.

 

I See in some Videos that on the Top Center of the Car Battery may be a Hold Down.

It is so hard to See what each End of the Hold Down is Bolted to?

To me it Look like the Hold Down Ends are Bolted to the Out Side of the Tray that the Car Battery Sits in?

Is this Right?

 

It is so hard to See what each End of the Hold Down is Bolted to?

To me it Look like the Hold Down Ends are Bolted to the Out Side of the Tray that the Car Battery Sits in?

Is this Right?

All batteries should have some sort of hold down. The last thing you want is for a battery to bounce around and short itself on the hood (though a lot of vehicles have the underside of the hood covered by non-conductive material these days).

Some have a bar across the top of the battery, some have something that holds the battery at its base.

 

Jumpstarting a car takes not a long time, so no need to select wires according to their rated current capabilities. But, if the cable is long then there will be a voltage drop on it and jumpstarting will be effected. manufacturers tend to use thinner and cheaper cables of course, engineering is done to cut the cost to the very limits.

 

Jumpstarting a car takes not a long time, so no need to select wires according to their rated current capabilities. But, if the cable is long then there will be a voltage drop on it and jumpstarting will be effected. manufacturers tend to use thinner and cheaper cables of course, engineering is done to cut the cost to the very limits.

For booster cables it might be OK to use wire not so capable of carrying so much current. But to start a car with a quite low battery it can take over 100 amps and more than 15 seconds. So I suggest avoiding those skinny cheap jumper cables that overheat so vary quickly. They are useless when they are needed the most.