Has anyone replaced the positive battery cable on their C3 (mine is a 1969). I have been chasing an intermittent electrical gremlin and found where "bubba" has spliced in a two foot or so section on the end of the positive cable. I thought the electrical wrap was there to protect it as it is where it lays on the transmission. Sadly, that is not the case. This may be the worst hack I have ever seen.

Has anyone accomplished this with the car on jack stands, as it goes up and over the transmission? The aim shows where the clips are, but I am not sure I get get them loose from a such a bad angle under the car.

If I can get the clips loose, I can tie the new cable end to the old one and (hopefully) pull it through like an electrician with a fish tape.

As an alternative, is there a different way to route the new cable and just cut the ends off the old one (out of sight, out of mind), since this is a driver and not any kind of real restoration? Future plans call for a 4-speed automatic upgrade, once the rest of the basics are in good shape, so the proper cable routing could be used then.

I have a couple of part rolls of 2AWG wire (in both red and black) and the crimping tool to make up my own cables, (left over from a solar power/inverter project) so I can make cables any length I choose.

Any suggestion or advice would be helpful.

 

the cable makes several sharp turns above the propeller shaft. i don't think there's any way you can pull new cable and tuck it up close to the body so that it clears the rotating parts. keep in mind that any contact between the cable and the metal drive shaft is going to result in an electrical fire and/or a battery explosion.
if you drop the propeller shaft you should be able to snake the new cable past the transmission. but there just isn't much room above the propeller shaft, and it's difficult enough to install a new cable without a motor, trans or shaft in place.

 

I did my 70 on jack stands. Really not that bad. I did not have the heat barrier any longer and my clips had no rust.

One of the easier things I have done.

Bill

 

I did this on my '68 with tranny and driveshaft in place. My heat shielding was missing though, so that made it much easier. Still I had some scrapes and cuts on my hands, but it wasn't the worst job I ever had to do. If the trans tunnel heat shielding was in place, I don't think I could have done it without pulling the tranny.

 

I did this on my 80 when I had the Trans out. So it was easy. I do remember that I thought it would of been next to impossible top do with the Trans in. If Your not concerned with originality You can just Cut off the old one as far as You can reach and Run the new however it makes sence. Strangly enough I don't think mine was near the Driveshaft at all its crosses the Trans. ( late C3) As a new Trans sounds like its in the near Future a little Bubba (OK that means You can't sell the Car) can be done in the mean time. If it was me I wouldn't be making my own Cables I'd be useing replacement Cables with the 75? and newer Side Mounts for the Battery. As they solve the Battery Corosion problem once and for all I have never figured out why every other Manufacture hasn't copied GM once again.

 

Thanks for all the inputs. Since a couple of folks have succeed, I am going to give it a try. Since it is an automatic, keeping it out of the drive shaft will not be a problem as it cross over the top of the tranny.

I really do not want to do a bubba job, unless it is a last resort. It just goes against the grain. The goal is to get the car reliable, then I can worry about upgrades like a new transmission.

 

Hi r,
The battery cable runs between the fiberglass tunnel and the foil covered tunnel insulator. I believe the are 1 or 2 cable clamps under the insulator... they may be the most difficult to get to.
Good Luck!
Regards,
Alan

 

Mine was replaced while the driveshaft was out... The cable saved my leg and maybe more when the drive shaft came loose while on the highway!! The cable stopped the driveshaft from coming into the cockpit with me...

 

Alan, the service manual shows the routing and where the clips are, but has absolutely no info on how to replace the cable.

U17 Yikes! Maybe I will not complain about the cable routing so much.

 

Hi Richard,
I agree, the AIM shows where it and the fasteners are, but is no help in the cable's replacement.
Even with some care I twisted off two of the studs.
Might you just concentrate on getting each end of the cable as clean as possible for a good connection, and then wait for your transmission work to replace the cable?
Regards,
Alan

 

I would Alan, but that splice under the car is really ugly. And it is certainly causing voltage loss. I will re-evaluate when I get back under it on saturday.

 

I see you are from Texas.

My 70 was a Texas car originally and all the nuts came off with NO problem. You may want to use a little PB Blaster JIC. Cars in areas where salt is used can be a nightmare.

It is a tight squeeze but it really was not that bad. Before I went all the way I made sure that every nut cracked loose so I knew whether or not I might twist a stud off. If a stud twists off it will really complicate things quickly. I am pretty sure the nuts are typical 1/4-20 so the studs will twist off pretty easily. Even if the nuts crack loose make sure the nuts do not bind or the heat created by removing the nuts will weaken the studs and they will still twist off. I used a wire brush on the threads to clean them up some before trying to remove the nuts form the studs.

Bill

 

Bill, that is good advice. This was a CA car when I bought it, and ruse has not been a major problem for other projects (like removing the gas tank) so i will go with caution. Thanks

 

Don't know if your insulation is in place or not
Also not sure if it's currently auto or manual

You can get to the two clamps at the tail of trans not too bad (even it you needed to drop the shaft)


But the next one is not going to be easy, it's way up in there. Exhaust might prevent access to it with any wrenches


And then there's one more up near the front that looks not quite as impossible. (above the cooling lines in this pic)


Probably best to try and zip-tie a new one to the old one for now and replace it right when you do get the trans out.

Then again, worse things have been done before
Mooser

 

Mooser, thanks for the pictures. They are far better than anything in the AIM or the service manual. it is an auto, but it will not be easy. I will just get started, and see what happens. I only have about 4 hours tomorrow, so I will just start and see what happens.

Again, thanks for the great pics. They will be a tremendous help.

 

Is it possible to solder the connection and thencover with heatshrink? At least that way you could stop the bubba problem until you can change it?

Bill

 

I replaced my cables with the drive train in place a few years back. Frankly, the positive was easier than the negative, because the negative has the big, hard grommet that needs to get pulled part way through the floorpan. What a PITA. Although I did mine while on the lift, you should be able to make the swap on jack stands without too much trouble.

Take your time and have some band aids handy. You'll need them. Also, you'll want to use a 7/16" SWIVEL socket in 1/4" drive. If you don't have this socket, buy it. You'll be VERY glad you did. You'll also need an extension or two for your ratchet. You'll need to GENTLY fold the foil backed insulation down to gain access to a few clips that are hiding behind the insulation.

Good luck on this project. It'll work.

 

Did you buy a LOTTO ticket that day ? Talk aboot luck.
Peace,,, moosie

 

I've got the exhaust off and did (with some screwing around) manage to get a swivel end boxed wrench on the two bolts above the trans. If they spring open when you loose them you may be able to pull the new cable through.

Good luck and let us know how it works out
Mooser

 

I did mine a few years back too with the driveline and tranny in the car, with the car on jack stands. A few of the fasteners are a real PITA but make sure you put all of them in. The reason I had to replace mine was that some Bubba didn't put all of the fasteners in when he had obviously done it previously and the cable finally sagged over time and it shorted to the drive shaft. Luckily I was pulling up to a stop light at the time, unluckily while pushing the car to the side of road using the driver side windshield frame I ran the tire into the back of my right leg and it ruptured my Achilles tendon. I replaced the cable after surgery with a plastic bag over my immobilization boot rolling around on my creeper. With surgery & rehab I put the cost of cable replacement at about $30,000....