Just purchased 2 new yellow top Optima's to put in. Are there any special precautions I need to take such as which battery to take out first or which wire to take off first to keep from screwing any of the electronics up?


Thanks in advance!


Randy

I did the passenger side first and everything was OK. I didn't know that it mattered.

it dont

No problem with other equipment but I suggest you remove both negative cables first so you won't arc anything if you touch ground with the wrench. When reinstalling, install both negative cables last in no particular order.

if you keep one of them connected while changing the other,will that keep your radio and time intact, or once you take off one cable its all over???

You do not want to have one “old” battery and one “new” battery connected at the same time. Disconnect both “old” batteries, remove them. Put in the “new” batteries and reconnect them. ALWAYS remove BOTH negative cables before removing either positive cable.
My ’01 retains the clock and radio presets and the computer memory for the engine. I have had both batteries out for several hours while I rebuilt battery boxes and did not loose anything

Hey, all. I would have thought that you would remove the POSTIVE(S) first. The ground could make contact with the truck (metal) and complete the circuit. By removing the postive(s) your are breaking the circuit, with no chance of accientally completing the circuit. Plus keeping the ground on longer is for a safety thing.
Keeping in mind I don't know much, so the above could be way out to lunch.

The theory behind removing the negative first is that you don't get a spark when it's pulled first if there is any kind of current flow going on. With these trucks, there's almost always something pulling a little power.


Emergency response personnel are taught to either remove or cut the negative side first on accident scenes for just this reason. It doesn't always work, on rare occasion I have had a spark when disconnecting the negative first, but it's really rare in my experience.


Any time you get a spark while tinkering with electrical connections on electronics, you're asking for a problem, so anything you can do to avoid that is advisable.

The reason for removing the negative first is that if you contact a metal part on the truck with the wrench while you have it on the battery nut, nothing happens. Think about it. The negative terminal is ALREADY connected to the body of the truck. If you are removing the negative connection and you “short” the wrench to the body or anything else you have not done anything ELECTRICALLY since everything is at the same potential. Once you disconnect the negitive the circuit is broken. If you take the positive off first and you short the wrench to ground, you have 12 volts across the wrench which has serious consequences.

One other thing. REMOVE all rings and jewelry before working around a battery. A friend of mine almost lost his finger when he got his wedding ring between a wrench and the body. If the ring had not been very small and light it would have burned his finger off. As it turned out he has a scare and the ring vaporized.Edited by: ag4gt

Hey guys. Makes sense. Thanx for the straightening out.

Thanks for all the replies guys. If this dang rain ever stops, I'll get 'em put in. Just wanted to be sure I did things in the right order so I don't mess up an expensive computer.


Randy

I'm just curious, why 1 year warranty yellow tops rather than three year warranty red tops. I think this question was asked before and some one had reasonable reply but I forgot what it was. Also the yellow tops cost considerable more.

Bill,


I have an Espar Engine Heater (http://www.espar.com/htm/Specs/water/hydro5.htm) on the truck and I frequently let it run for 2 or more hours at a time in the winter. Thats why I went with Yellow tops.


Randy

In a dc circuit, current flows from negative to positive. Removing the neg cables first minimizes the possibility of completing the circuit from neg to pos and allowing current flow. I have witnessed someone shorting the pos side of a battery to ground. It wasn't pretty. The top of the battery went flying and he received burns to both hands and arms. Always remove the neg cables first. A 12vdc battery in a 4 cylinder car(a lot less cca than our batteries) can put out enough current to kill a person. I used to work with a person that lost a foot due to shorting a battery out through his body. It literally blew his foot off.

Adding to what was stated above;


I didn't see this mentioned so I thought some may need to read it. These steps are very important.


Always disconnect the neg first and connect it last. Never disconnect the positive side first, and never connect it last.


As for rings and such, that is also very true. Although I used to work on Diesels in the Army and nothing happened to me. I did see what can happen. A fellow worker arced across the positive side with his ring. To make a long story short. He ended up losing the ring finger.Edited by: hdmax

I understand and agree with removing the neg cable first for the reasons ag4gt gave, but how did your friend flhrciblueice lose his foot? Exactly what kind of circuit did he complete with his foot? I know if you grab the postive battery post and grab the ground too you don't get a shock because current dosen't flow through your body very well, but if you grab the postive post with one hand and then the postive battery cable with the other hand and then try to crank the starter over that could do some damagehttp://www.dieselplace.com/forum/smileys/Dead.gif

Standing in water puddle(up over the top of his shoe), ground to frame already removed, bad ignition switch(shorted). When he went to remove the positive cable, his other hand was on the negative post. It was not a pretty sight. Part of his foot was still there, but had to be removed for the prosthetic(sp?). Edited by: flhrciblueice

After reading some of the opinions here I went out and removed both negative cables and reinstalled them. They arched both ways. Later! Frank

I am working on a post that will tell you how to prevent the arcing and sparking.

The arc when removing the negative cables is the current attempting to jump across the air gap. You are touching the truck, so there is no difference in potential(voltage) between you and the negative cable. Therefore, you don't get shocked when removing the neg cable and it arcs. Unless you pull all fuses to equipment(clock, etc) that are pulling power, there will most likely be a small arc when you pull the cable off.

If you remove the positive first and any part of the wrench touches metal while in contact with battery post, you will get a nice spark. This in turn will cause you to pull your hand back real fast, which will probably require you to tape up your knuckles to stop them from bleeding all over the truck.

A 12vdc battery in a 4 cylinder car(a lot less cca than our batteries) can put out enough current to kill a person.* I used to work with a person that lost a foot due to shorting a battery out through his body.* It literally blew his foot off.

I can't even come close to believing this. Sure the battery can put out enough current to kill a person, but there's no way a body could draw that current. Just to draw an amp and dissipate 12 watts through the body you'd have to have a body resistance of 12 ohms. If somebody had that low a body resistance they'd have been long dead before touching the battery. And 12 watts wouldn't come close to blowing off any body part other than maybe a hair. I'd love to have somebody explain to me how this could happen as stated. Did you see this happen in person? Ship it off to mythbusters!

Have to agree with Wayne on that one. I used to work on tube type transmitters and know that DC will knock your whatever in the dirt (in the 200v to 400vdc range, anyway,) while the AC causes your muscles to lock down causing you to hang on. Just can't see anybody's resistance being low enough to cause enough current flow to do that.

I'm betting that all the guy's who have worked any time at all with electricity are laughing after reading the replies to the original post. I've worked with electronics and electrical equipment since 1948 and have never been shocked by a 12Volt battery or even heard of anybody being shocked by one let alone suffer body parts damage. I've had shocks from bothe AC and DC countless times. I've had several RF burns from low power to hight power rigs. I once touched a antenna connection on a Loran transmitter and it burned a nice hole in the back of my hand and burned the bottoms of both my feet. RF burns if from high enough power rigs can burn clear into the bone. Thats not crap , I've had it happen a couple times. Like the guys say when working on batteries disconnect the ground first, when two batteries are hooked in paraallel disconnect both negative connections before touching the positive leads. Do not disconnect these leads if the truck is running as the batteries may be generayting gas and be highly supceptable to blowing up. Don't smoke or get any flame close to the batteries. When you have spark from disconnecting the negative leads this means you have something in the truck drawing power. The only way to avoid that is to pull all the fuses on the battery side of the trucks electrical system. None of us do that though. To avaoid the sparking condition I disconnect the ground lead at the grounding point before disconnecting the negative lead from the battery, that way any sparks ar distant from the batteries. If you are afraid of changing the battery, get some else to do it. When a battery blows its the acid that gets you. For electricans current flow is positive to negative externally. For tube type electronic technicans current flow is negative to positive inside the tube and positive to negative out side the tube. I've seen many an argument between electricans and electronics technicans about current flow and they are both right in thier beliefs. Some of you guys on here are probaly not fanilar with the vacuum tube but I know one is. He probaly knows about doides, triode pentode, tetrodes,getters, high mu and stuff like that. Probaly has even changed a few mercury vapor rectifiers in his time to. I've still got a few tubes laying around from doing radio repair here at home twenty five years ago. You guys enjoy your trucks and just be careful.

A 12vdc battery in a 4 cylinder car(a lot less cca than our batteries) can put out enough current to kill a person. I used to work with a person that lost a foot due to shorting a battery out through his body. It literally blew his foot off.

I can't even come close to believing this. Sure the battery can put out enough current to kill a person, but there's no way a body could draw that current. Just to draw an amp and dissipate 12 watts through the body you'd have to have a body resistance of 12 ohms. If somebody had that low a body resistance they'd have been long dead before touching the battery. And 12 watts wouldn't come close to blowing off any body part other than maybe a hair. I'd love to have somebody explain to me how this could happen as stated. Did you see this happen in person? Ship it off to mythbusters!


You didn't read my post explaining how it happened did you? With a shorted ignition switch and him being the negative conductor, it will put out all the current it is capable of to overcome his body's resistance and try to start the engine. Lower voltage = higher current. I wish it weren't true. I responded to the call and it wasn't pretty.

I have always heard that it isn't the volts that kill a person, it is the amps! And that as little as one amp is needed to kill, it depends on how the current travels through your system.


I do not know how true this is, but it is food for thought!

You didn't read my post explaining how it happened did you?* With a shorted ignition switch and him being the negative conductor, it will put out all the current it is capable of to overcome his body's resistance and try to start the engine.* Lower voltage = higher current.* I wish it weren't true.* I responded to the call and it wasn't pretty.

I read the post. What you are saying is absolutely impossible. For current to flow it takes something to produce the current and something to draw the current. There is no way a human body could draw enough current to do what you say at 12 volts. If this is really a true story then something you are not aware of happened, like a 440 volt source being accidentally connected to the car, metal implants in the body, etc. I hate to pull 'athority', but I have an EE degree and lots of years experience, and there is either some other explanation or this didn't really happen.Edited by: Wayne Dohnal

A 12vdc battery in a 4 cylinder car(a lot less cca than our batteries) can put out enough current to kill a person. I used to work with a person that lost a foot due to shorting a battery out through his body. It literally blew his foot off.

I can't even come close to believing this. Sure the battery can put out enough current to kill a person, but there's no way a body could draw that current. Just to draw an amp and dissipate 12 watts through the body you'd have to have a body resistance of 12 ohms. If somebody had that low a body resistance they'd have been long dead before touching the battery. And 12 watts wouldn't come close to blowing off any body part other than maybe a hair. I'd love to have somebody explain to me how this could happen as stated. Did you see this happen in person? Ship it off to mythbusters!


You didn't read my post explaining how it happened did you? With a shorted ignition switch and him being the negative conductor, it will put out all the current it is capable of to overcome his body's resistance and try to start the engine. Lower voltage = higher current. I wish it weren't true. I responded to the call and it wasn't pretty.





If that were the case touching both terminals at the same time would short out the battery and kill you. It doesn't happen because the resistance in your body will not allow enough current to pass through you, with only 12 volts of potential, to even feel anything.


Adding a starter motor in series with the battery and your body only increases the resistance of the circuit and thus even less current will flow.


"lower voltage = higher current" is a false statement.


lower resistance = higher current

Ok so now I'm really confused:


Is what I wrote earlier and always thought to be true........ True or Not?


If you put your self in the middle with the battery in one hand and the starter cable in the other and then turn the ignition switch over to Start..... Will you or won't you get a shock?


How about if you add wet hands or feet.... Does it make a diffrence?


Just wondering Diesel Dragon


P.S. AC is so much easier... it seems it will kill you no matter how you touch it. As long as you are grounded ....Right?

You didn't read my post explaining how it happened did you? With a shorted ignition switch and him being the negative conductor, it will put out all the current it is capable of to overcome his body's resistance and try to start the engine. Lower voltage = higher current. I wish it weren't true. I responded to the call and it wasn't pretty.

I read the post. What you are saying is absolutely impossible. For current to flow it takes something to produce the current and something to draw the current. There is no way a human body could draw enough current to do what you say at 12 volts. If this is really a true story then something you are not aware of happened, like a 440 volt source being accidentally connected to the car, metal implants in the body, etc. I hate to pull 'athority', but I have an EE degree and lots of years experience, and there is either some other explanation or this didn't really happen.


I am unsure about the metal implants, he may have had something like that. Pull all the authority you want, means nothing to me. I know it happened. When we are troubleshooting equipment at work(I am an experienced electrician), we end up teaching new things to our "experienced" EE's on a regular basis, and no I am not doubting your experience or expertise. I don't want to get in a pi$$ing match with anyone over this as I know it happened. Electricity does not always follow what theory says it should. If I put my meter across my body(and everyone is different) when not sweating or otherwise wet, I will read approximately 4 M ohms. Calculate the current draw and you would come up with 3.45 m amps. That is with nothing loading up the circuit. With a loaded circuit the battery would pull down to 12 v in theory and cause that to go to 3 m amps. However, a loaded circuit is going to try to pull through that resistance causing more heat. If you add in a lot of sweat and water, the resistance will go down. There may have been extenuating circumstances in this instance, we could only go by what he stated. I don't know how much current it would take to produce what happened and I don't know how much current it would take to kill a person, and I hope I never find out first hand. Edited by: flhrciblueice

"lower voltage = higher current" is a false statement.


lower resistance = higher current








I apologize for that statement. I was working on a power transmission(high voltage) problem at work at the time and got a little crossed up. I stand corrected.