Hi guys.
I need advice on jump starting a 1988 7.3 IDI using a booster pack. i am not sure which battery to connect to as i do not a not want to fry anything. What would be a good jump starter.

Many thanks.

 

I believe i is the battery on the right...in front of the battery on the left mine hase a big lable that says "dont use this one to jump start", so I have always used the other one without issue.

another thing to keep in mind when using a booster pack (never tried this, so just spilling thoughts)...your gonna need a lot of power...if your motor is totally cold, you will need the glow plugs (unless you use the block heater) which I believe draw in the neighborhood of 150amps for up to 20 seconds, then you will hit the starter which will pull another 200 while cranking. If you are using an industrial unit you might be allright, but I could see a wal-mart special getting sucked dry on the gp's alone.

 

Always use the secondary battery, that's the one on the driver's side. You probably know not to use starter fluid but, you can use a shop rag dampened with gasoline held over the intake plenum.

 

i am....thats what I had originally thought too (I can see logic in both sides of the argument as to which battery to use as far as equalization and load distribution etc)...like I said, what threw me was on mine there is a big red label above the drivers side headlight "warning - do not use this battery for jump starting" I am not by any means claiming to be an expert on jumping a diesel, just sharing what I saw. Could this possible be refering to using the turck to jump-start another vehicle????

 

If my batteries are dead in my truck, if possible I jump to the passenger side battery.
It's closest to the starter.

Also if my batteries are dead and I am jumping it with a car, connect the cables and let the car charge the batteries for 10 or 15 minutes before you even try to start the engine.
That little 500 CCA battery in a car with a 55 amp alternator don't have enough juice to cycle the glow plugs then crank the engine.

If I am jumping another vehicle, I go with the closest battery to the other vehicle.

 

timothyr, is the 6.9 set up different than the 7.3, as for where where the starter solenoid is mounted? Mine is mounted above the passenger wheel well....

I just checked my owners manual and factory service manual and, neither is specific about which battery to use when doing a road side jump from vehicle to vehicle....only a repieted warning not to connect the negative jumper cable to the dead battery because any spark from moving it could ignite the gas from the jumped battery and explode.

I didn't find anything about charging the batteries while still in the truck either, and that is the context I remember the instructions to use the last battery in the series.

I'm curious now, what is the warning on your truck all about and, what and why is the correct procedure for charging in series batteries in system??

 

The batteries are in parallel in our trucks.

Positive and positve on one cable, negative and negative to the engine block.
12 volts all the way around.

Series has positive to starter, negative on that battery to the positive on the next battery and that battery negative to the engine block.
Using 12 volt batteries you wind up with 24 volts to and from the batteries.

 

dave, you are correct as far as ending up with 24 v if in series....as far as which battery to use, the 2 arguments i see are that using the battery furthest away from the started would keep the batteries better equalized (current is running through both of them); on the other hand, using the first battery in the chain (closest to the starter) would allow a shorter path to load, and less current absorption by a second battery.....

like i said....just a big red lable that says dont use this one.....

 

Looking at it from an electrical standpoint, the best place to hook the positive jumper cable would be on the battery lug on the starter.
Not usually very practical, but in reality the best place to connect the cables.

If you are trying to draw a given amp load through a wire, the longer the wire is and the more connections there are in the wire, the higher the resistance is to the current flow.

The starter I run, a Mitsubishi gear reduction draws 3.6 kw or 3600 watts.
Assuming a 12 volt current supply, that is 300 amps draw.

So you have two dead batteries, which will be trying to charge when you hook up the jumper cables.
If you put the cables on the drivers side battery, both batteries will rob some of the jump current from the start current before it ever gets to the starter.
Then as it goes by the passenger side battery, the glow plugs are also drawing current as well as any other electrical devices that are on.

Then there is the fact the cross over cable between batteries is a 2/0 cable and has two more connections added to the 2 connections in the passenger side cable that is 3/0 cable down to the starter.

Bottom line, unless you are jumping your truck with a semi that has huge batteries and using 3/0 jumper cables, the closer to the starter you hook the cables the better your chances of starting are.

 

damn i like this forum....its nice having people around who understand booth motors and electricity....

 

Master electrician and electrical contractor is only one of the many hats I wear in my other life off the forums.

Master plumber as well if you want to talk pipes.

Heavy equipment operator if you want to dig a hole or fill one in.

Thinking hard about taking the engineering contractor test this winter just for fun so I can pocket what I am paying engineers for now when I do large retaining walls or bridges.

 

all I can say is you are the man....and I say that with no sarcasim whatsoever.

Nothing impresses me more then someone who knows alot, but most of all knows what they dont know; to me life is a never ending quest for knowledge, and in that search it was many of your posts that I sat and silently read that made me buy (and fall in love with) my idi.

but your still not getting a check!

 

All I can say is I tried.

55 and still hitting the books and taking tests so I can learn and do more.