Hey guys, truck won't start, battery is good, last time this happened (about a year ago) it was corroded ground wires. Fixed that and haven't had problems since. I recently upgraded the three main ground wires (battery to chassis, battery to block, block to chassis) to #2 welding cable because I am also upgrading my alternator and going to a dual battery set up very soon. I don't see why the truck won't start though because it is doing the same thing it did before when I had grounding issues, but all the grounds are new and good this time? I can boost the truck from another battery but it will only work if I connect the ground to the chassis, not the negative terminal on the battery (this is why I think it has something to do with the ground wires, but I can't see what the problem is?) Any help would be appreciated, thanks in advance.

 

Grab a volt meter and see what kind of voltage drop you get from the battery "-" terminal to the engine block while you try to start the truck. Should not see much of any drop there, but if so, check all the connections. Don't just look at them, disconnect and clean (wire brush) them and put back together. I like to use dielectric grease or an oxidation preventing grease on the contact points. Also, any contacts bolted to sheet metal or the frame I like to hit the contact point with sand paper to get a bare metal contact.

 

Just curious what type of ends did you put on the ends attaching to the vehicle??

What kind of battery terminal did you use?

I would guess your problem lies there someplace. A bad crimp or a bad connection at the battery

I do this all the time as soon as a Toyota passes through my shop I use crimp on Copper lugs and East Penn Manufacturing (DEKA Battery) marine battery terminals. I have found them from other vendors but DEKA is a customer of mine so I hit the outlet on the way out.

Like 4 Crawler I might even go a bit more I always use new bolts using copper never seize on the threads cleaning the contact area where the lug contacts

 

They are brand new ground wires with brand new crimp on copper lugs. Here are the terminals I used:

http://www.canadiantire.ca/AST/brows....jsp?locale=en

I attached them by putting the copper lugs on the bolts. Also, there is the ground wire from the back of the block to the firewall... could that have something to do with my problem?

I guess I'll have to play around with it today and see if I can make it go. What do you guys think?

 

One easy test you can do to check if it is a grounding issue is to grab a decent set of jumper cables (should be good heavy gauge wire, not the cheap ones that are all insulation and no copper!) and clamp the black cable between the battery "-" terminal and a good clean part of the block. Then see if it starts better. If so, you have a ground issue. You can then move the block end of that cable to test out the various ground straps by hooking it to one end or the other of each ground strap until you find a strap that if you bypass it, engine starts, but if you don't bypass it, engine doesn't start.

I used that technique to debug a starting problem on my DD. Ended up installing an extra ground cable from the chassis ground bolt to the engine block and that made starter cranking speed a lot faster.

 

That's what I tried right before I read your post jumper cables between the negative post and my battery mounting box, truck started up just fine. I'll try putting the jumper cable on my ground wires and see if the problem is with the battery terminals or not. I'm glad its not as serious as I thought! I wasn't a happy camper because I'm trying to get this dual battery set up finished and my alternator is crapping out at the same time, so grounding issues aren't going to be too big of a problem. Thanks guys