[condor]

What is the correct procedure to jumpstart ?
You have two cars, one with a dead battery and another with a good battery. You use the cable to connect both battery's.

What do you do next - do you start the car with the good battery, step on the acclerator to get some higher rpms and then try starting the car with the dead battery? [This is what I have always seen being done.]

Or can you safely try starting the car with the dead battery while keeping the second car's engine off ?

TIA.

[Surprise]

http://www.team-bhp.com/forum/techni...highlight=jump

Might be helpful

[condor]

Surprise, thanks again - Second time you're providing me with links. Wonder how I missed a thread as recent as this. Had done a search, but used 'jumpstart' instead of 'jump-start'.

The ***** mechanic who came didnt seem to know the correct procedure. My question came up because he said the second car [car with a good battery] doesnt need to be started while doing the jump-start.

So, now my question is - since the engine of car with the good battery was not running when the jump-start was done, will it cause any damage to this [good battery] car ? The connection procedure was fine, but that seems a secondary point now.

[ECM]

Avoid Jump start in cars fitted with ECM/ecu.

[condor]

Should've remembered - RTFM !. While I was on track with the part about keeping the engine of the second car running, there was more in the manual:

1. Connect +ve to +ve [battery to battery].
2. Ground both -ve leads to respective earth [not battery].
3. Start engine of second car, let it settle down to steady rpm.
4. Switch off all electricals in both cars.
5. Start the car with the bad battery.
6. Let both engines run for about 3 minutes.
7. Disconnect -ve leads, disconnect +ve leads.

But one question remains for me - is any damage possible if the second car's engine was not running during the start.

ECM, would you have any more details on why this shouldnt be done for cars with ECM/ECU?

[ECM]

Condorji,I never advise jump start in any cars fitted with ecm but rather I prefer to put a new battery in it and start it to avoid any probs.There is no need to risk the brain of the car by JUMP method,better take out some "pasina"out of our body,remove dead battery and replace it with a working one.No expert will advise jump method in cars fitted with ecm and logic is simple.Forget jump,ECM cars are extremely sensitive against Xtra fittings,do refer car manuals(ecm fitted) where they clearly suggest not to attach any xtra acce.in the car to avoid prob to ecm(but still we do is a diffrent story!)/

[Shakensoul]

Was looking around for a good battery jumper cable in Lajpat Nagar, Delhi, couldn't find any shop which keeps them.

Where can I get the cables and how much will they cost ?

I read that 4 guage cable is good enough, can i buy any 4 guage electric cable and make a jumper cable for myself ??

[aah78]

Originally Posted by condor

But one question remains for me - is any damage possible if the second car's engine was not running during the start.

you run the risk of damaging the second car's 'battery'.
when you crank the first car, after making all your correct connections, there will be a heavy surge due to the dead battery in the first car.
now, if the second car's engine isn't running, then it's likely the second car's battery will be discharged due to the surge.
keeping the second car's engine running ensures that the alternator is continuously charging the second car's battery so that it continuously generates enough power to start the dead battery in the first car.

Originally Posted by ECM

Condorji,I never advise jump start in any cars fitted with ecm but rather I prefer to put a new battery in it and start it to avoid any probs.There is no need to risk the brain of the car by JUMP method.No expert will advise jump method in cars fitted with ecm and logic is simple.

your method is probably better but what i'd like to put across here is that there isn't a problem in jump-starting a car with a dead battery - carburetted or otherwise.

your car manual will list how to properly jump start a car with a dead battery (pretty similar to what condor has mentioned). now, if one doesn't follow directions properly, there is a very good chance one is going to make a huge mess of things (e.g. ruin both batteries or even get zapped) but otherwise there isn't any risk.

please note that i'm referring to jump-start here and not push-start. also, i'm not referring to any aftermarket accessories that may or may not affect the car's ECU.

i've myself used this method a couple of times and i can back-up my claim via further clarification, if necessary.

Originally Posted by Shakensoul

I read that 4 guage cable is good enough, can i buy any 4 guage electric cable and make a jumper cable for myself ??

2 gauge is even better. yes, you can make your own jumper cable but make sure your connections are clean, properly insulated and tight - any loose connections will cause an electric arc (sparking), which will damage electronic and other metal/plastic components

[caliper]

Originally Posted by ECM

Condorji,I never advise jump start in any cars fitted with ecm but rather I prefer to put a new battery in it and start it to avoid any probs.There is no need to risk the brain of the car by JUMP method,better take out some "pasina"out of our body,remove dead battery and replace it with a working one.No expert will advise jump method in cars fitted with ecm and logic is simple.Forget jump,ECM cars are extremely sensitive against Xtra fittings,do refer car manuals(ecm fitted) where they clearly suggest not to attach any xtra acce.in the car to avoid prob to ecm(but still we do is a diffrent story!)/

ECM, are we assuming that cars will always get a dead battery right in front of a battery shop? If you get a dead battery on the highway, you'll just have to jump start.

[razor4077]

Originally Posted by mithun

Why does the Jump Starting works only in the Carburettor models ?

This is not true. Vehicles with fuel injection systems can be jump OR push started.
Lol... I found out the hard way. How many people have asked their date's father to push the car so it starts?
Starter had conked out on my Accord so had to stoop to such levels!!

[Shakensoul]

Originally Posted by aah78

2 gauge is even better. yes, you can make your own jumper cable but make sure your connections are clean, properly insulated and tight - any loose connections will cause an electric arc (sparking), which will damage electronic and other metal/plastic components

Thanks for the reply.

Where do i get the cable ? From an electrical store or an automobile shop ? Any particular type of cable ?

[Shakensoul]

How do you covert gauge to mm ??

x gauge = x mm ??

[pogusingh]

Please excuse me for my novice question
When we do the push start in second gear, what position should the key be in. Normally you need to rotate it to get the vehicle started.

[WhiteKnight]

Originally Posted by condor

Should've remembered - RTFM !. While I was on track with the part about keeping the engine of the second car running.

But one question remains for me - is any damage possible if the second car's engine was not running during the start.

This is not necessary though advisable. Starting an engine, whether it is of first car or second car has the same effect on the battery except for the additional resistance provided by the cable. If you use a low quality cable, chances are that you burn more power on transmission, thus over-loading the battery. Keeping source car's engine running, ensures that the source battery is not strained.
NO damage to the source car's engine in any case

Originally Posted by condor

2. Ground both -ve leads to respective earth [not battery].

Don't think we need to do anything here. Aren't the negative leads of the batteries already grounded?

Check, double check and confirm that the +ve of one battery is connected to the +ve of another. If you mess up and connect +ve to -ve, you'll burn your hands seriously (and the cables too).

Be extremely careful with this part.

[WhiteKnight]

Originally Posted by WhiteKnight

Don't think we need to do anything here. Aren't the negative leads of the batteries already grounded?

Oops...That looks confusing. What I meant is, connecting -ve terminals of both batteries have the same effect as connecting earthing points of both cars.

Those uninitiated folks, please follow condor's list as bible.

One more point. When connecting the jumper cables, ensure that connection to the +ve of the source battery is done at the end. This way you can ensure you are not holding a shotgun in your hand