Originally Posted By: BrocLuno
First look at the way the cables connect to the battery in that car? They are likely the old not-so-good side mount cables. They were hard to keep tight and clean and often lead to poor energy transfer ...
If the car was converted to top post style with robust cables, then I'd be looking at both ends of each cable. The terminals need to be clean and tight on the battery. But the motor ends need to be very solid too.
The ground is especially sensitive. It must carry the same current back to source (battery) but it has no usable voltage to help it along. The voltage has been used up by the device (like the starter motor). So it needs to be really clean and well done.
I always start on the ground side. Pull the battery cable off and examine the ends. The one that bolts to the motor is often just a mediocre crimp. If it looks serviceable (?), clean it with a wire brush, put some tinning fluid/paste in the bolt hole and use your Bernzo torch to warm it until it accepts solder in the bolt hole. Now you know the wire and the lug are solidly connected.
Go to the bolt that held it on the engine and look at it and the surrounding bits. If they are corroded (?), clean them. WD40 and turn out the nearby bolts a turn or two and re-torque. That will give you fresh contacts for a while. Look at the braided ground strap that goes from the engine to the fire wall. If it looks poor, do the same; or replace it with a new heavy duty home made one. Your radio, windows, instruments, dash lights, etc. will all thank you
Now look at the Positive Bat (+) cable. It'll be harder to get to as it will run down to the starter motor, so you'll need to be up on ramps. Same deal. Take it off and look at both ends. If the bolt-on lug looks serviceable (?), do the same as the ground cable, clean and solder.
If any of these look corroded and frayed, just take them to the auto parts house and replace with new same length. If you can part with the extra cash, get new 6-volt cables same length. Take them home, tin the bolt-through ends and solder them.
Also take your battery to the shop/auto parts house and have it tested. If it tests well, you're OK. If it's marginal, replace it. Get as many cold cranking amps as you can afford in the size that fits your battery tray. If it was a side mount battery, now is the time to switch to top mount. You'll need new cables at the same time. Never use repair ends to convert, you will not start on a cold winters day ...
Often, on this generation GM vehicles, the Bat Neg (-) ground cable) runs from the NEG post to the alternator top bracket. So to make this work well, you need to remove the self tapping cable bolt from the bracket and insert a Stainless Steel bolt about 1" ~ 1 1/4" up from the bottom through that hole and snug it up.
IIRC it's 5/16" bolt but may be 3/8" ... Put a star washer under the head of the bolt before inserting up. Grease the threads before inserting. Now you have a stud to put your cable back on with and you can use a flange nut on top to snug it down. More clamping, no thread stripping, no future corrosion, and more surface area to flow current
All this stuff is available at a good hardware store for a few $
Then look at the bolts that hold that top bracket to the head and block. Prolly three of them ... Pick the easiest two without taking one out of the water pump. Take them out and clean the threads on a wire brush. Put grease on them when you re-insert. Use new lock washers. You now have a very strong clean ground system. Your car will start easier all the time, but especially in cold weather
If you decide to make a new ground to the fire wall, you can get a crimp and solder lug that fits that same bolt on the alternator bracket and crimp and solder it to at least a #8 or better, #6 stranded wire. The other end can go under a hood hinge bolt or some other modestly large bolt holding the bodywork together. Clean that bolt too. Use grease when you reinsert it and a new star washer between the bolt head the new ground wire HD lug that you crimped and soldered on.
The grease prevents crevice corrosion for the foreseeable future. And stops the bolt from rusting in place. In the future (like each fall) to renew your ground point, all you do is back off each connection a 1/2 turn and re-torque. No need to go crazy tight. Just turning and re-torquing will renew the contacts
All this will take a few hours. Once done you will not believe how well it will light and idle. How well all your accessories will work. It won't be a new car, but it'll act more like one. And on a cold rainy/snowy/sleet night when it's absolutely miserable out, you'll just slide behind the wheel and it will light right off, and you'll drive off with a smile
Thanks so much. It looks like the negative goes to a lug that's underneath the mounting plate for the ICM/coil packs. Spade terminal on one end. It's a 3400 Series V6, the 3.6L.
I have a DVM is there a way to check that I'm getting decent ground before I year into it?
And yes they are side mount. I really hate them too.
I'll get the battery tested too. It's only 1.5 years old and have no reason to think its bad, but why not. O'Reilly's will do it for free
