LB7: Electrical Gremlins

[durallymax]

Did a set of HGs in my uncles 2001. Pulled the cab off to complete the repair.

Now it is acting weird. It will only hold 11.5volts until the glow plugs shut off then it will jump to 14.

Alternator is fine, and batterys test fine and are only a few months old.

I also noticed that while the passenger side battery was hooked up, I went to hook up the drivers side battery after cleaning the terminals, and it sparked. Now in all of my previoud experience if one is hooked up the other one doesnt spark when you hook it up.

This really leads me to thinking its a bad ground and only running on one battery. Ive forgotten grounds before, so I double, triple and quadruple checked them and everything appears to be in order.

Any other idears??

Thanks.

 

[TheBac]

Low voltage on start up is normal.

I get a spark from the pass battery when I hook it back up, too.

Only ground I can think of during head gaskets would be the one to the firewall, but it may not be making a good connection anyway. May also want to clean the connection at the DS bodymount...could be salt-corroded.

In fact, remember all those trans codes I asked about a couple weeks ago, that I thought were NSBU related? They just wouldnt go away, so I figured batteries. I went to take them out, and found the + terminal on the primary batt was loose, and the - terminal on the pass batt was loose. Tightened them up and, walla, no issues. Must not have snugged them down when I redid the motor, and it only showed up when it got cold out. So doublecheck the cable connections for contact, too.

 

[durallymax]

I know the low voltage is normal, but this voltage will sometimes drop too low and shut the computers down.

I pulled the cab off so basically every ground was taken off.

His primary connection at the one battery was loose, I tried a new terminal with no sucess.

I think once I get done with the injectors on our plow truck I will go through his truck and clean everything and check it all out again. It is an 01, driven through wisconsin winters.

 

[TheBac]

Mine went really low, too....to the point that the truck wouldnt start one morning. Thats what got me looking.

Yeah, recheck all the ground connections. You'd have a better idea if there were any others besides the two I mentioned, since you had the cab off.

 

[durallymax]

its acting like its only running one battery, guess ill test a few more things out.

 

[cletus]

i have a 02 lb7. when i chaged the glow plugs and turned the switch on the glow plug controller started smoking. anybody got any answers

 

[JD4440]

i have a 02 lb7. when i chaged the glow plugs and turned the switch on the glow plug controller started smoking. anybody got any answers

Start a new thread where the title will catch someones eye ?