alternator acting up

Nathan Winters natewin at
Mon Jun 25 11:30:14 EDT 2007

I'll try my best to describe what I did here.  Constructive criticism is welcome.  Try to keep the flames to a minimum if you disagree with my methods ;)  

Before doing this the voltage meter on the dash would be fine one day at 14v, the next it would sit at around 11.5v to 12v like the alternator isn't charging.  Sometimes the car wouldn't turn over, the solenoid would fire but no cranking.  Even jumping from the battery to another vehicle would do the same thing, jumping from the post under the hood would crank fine.  I could grab the starter wire inside the hood at the frame rail and push / pull it towards the firewall, this would help starting / charging for a short period of time.  

Once I completed the cable replacement it was like I had put in a new battery, the car went from cranking slowly (when it would) to cranking very quickly, night and day difference.  I couldn't believe that the original wire had failed this badly and that they had gone from a 2ga wire down to 4ga.

I did this repair on 3/19/07 (snow on the ground helped cool my solder joints) and have driven 8200 miles since.  I run a sound system in the car off of a 300w Rockford Fosgate amp.  The voltage needle stays well above 13v at all times, turning lights on and running the stereo seems to make little difference.  

0ga or 2ga cable, about 8 feet depending on where you cut etc.
Lug for end of cable at battery
Copper tube for splice
Heat shrink
Propane torch (think plumbing)
Pipe cutter
Flare tool (maybe)
Wire cutters
Vice grips
the usual assortment of hand tools.

I stared out by finding the splice.  I think the SJM site tells you how.  I had to pull out some of the plastic panel behind / under the glove box to get the carpet up enough.  You really need to get to the firewall.  The spice is under the passengers feet pretty much.  You will also have to pull the trim piece at the door sill to expose more of the 2ga cable that runs to the battery.
Do not try to pull this cable through the firewall to the engine compartment, the splice is far to big to fit through the grommet and will pull the grommet out of the firewall.  This I remember being the most difficult part, getting the grommet back in once I had pulled it out.

Once I found the splice I inspected it.  It is under some heavy duty heat shrink tubing and it looked fine to me.  I cut the tubing off and things didn't really look too bad from a crimped cable splice standpoint.  I found that the 4ga cable running to the starter was in bad shape though, the strands of wire were entirely white.  I'm assuming they were copper and just incredibly corroded.  This was along the entire length of the 4ga cable

I cut the spice out and pulled the 4ga cable to the starter through the firewall.  I then pulled this cable from the starter entirely to measure what length the new one should be.  You will have to pull the airbox to get at the wire path.  A jackstand under the front of the car is all you need to get to the wiring at the starter.

I cut the large cable to the battery from the splice back to a point that I felt had really nice clean wires.  This cable didn't have any corrosion at all and I felt it could be reused, you will need to make sure yours is as well or you will have to run cable all the way back to the battery.

Next I purchased some 0 or 2 gauge  cable (I forget which, about the same gauge the one from the battery) from a stereo store.  I hoped it would be good enough for starting the car off of, someone let me know if there is an issue using it ( i haven't had any trouble for the past 4 mo)  They sell it by the foot and it seems like nice stuff.  I then went and purchased a lug to solder onto the end of the cable.  I like the lugs that look like they are made of copper and have a nice cup to accept the cable.  You can get them at most hardware / auto parts stores I've found.  Compare your original starter lug to these to get the correct hole size.  I was able to get close, it is a bit bigger hole but I haven't had any issues.  Don't worry about the 90deg bend, I didn't have a problem hooking it up.

You will also need to get some heat shrink tubing that will fit over your large cables and the splice, I used two layers. I even put some over the starter lug connection as well.

Next I fed the cable through the firewall following the path of the original.  The reason I did this is b/c the grommet in the FW really wants to be used from the inside, plus I couldn't even see if from in the engine bay.  If your new cable is considerably bigger than the original you may have to make the hole in the grommet larger or just try lubing the cable to get it to feed through.  Once the cable was through I pulled enough out beside the car and put the starter lug on.

Here is how I soldered the lug to the cable.  1st I put some flux inside the lug-solder-cup, then I cut some beads of solder and filled the bottom of the cup with them.  I put some flux on the trimmed piece of cable and put that into the solder cup.  I then crimped the cup with a pair of vice grips (it is too stiff for my tv crimp tool I used on the splice section).  Next I used the propane torch to heat up the lug and added solder to the wire to get a good solder joint.  It sucked in quite a bit of solder and seemed good enough.  I put some heat shrink at this joint when it was done.  Next feed the cable along the original wire path and fix it to the starter.  You can now pull the remaining slack back to the inside of the car to cut to the correct length.

Here is where I had to get a bit creative with the splice.   I figured out the correct length for the cable to lie on the floor of the car as it did originally.  Once cut to the correct length I unhooked it from the starter and pulled a bunch back through the firewall.  I also pulled the wire from the battery out as much as possible to get the wire out the door as far as I could to make the new connection.  Next I cut about 4" of copper tubing (the flex kind used for gas lines).  This tube had an ID of just over the stripped copper wires that were going to go into it.  I flared the front of the tube to help get the wires in, it was quite snug putting them in.  I put about 2" of one cable in the copper tube, stripped and fluxed, and used a crimp tool ( the kind that makes cable-tv cables, a nice hex).  I made this hex crimp along the entire 2" section of tube over the wire inside.  Next I cut some more beads of solder and dropped them in the open end, quite a few actually. 
 Make sure you have your heat shrink tubing on the wire before assembling the last cable, I used 2 pieces, enough to insulate twice.  Now I put the remaining cable 2" stripped section (with flux) into the open copper tube.  I crimped this section down the entire length.  Now with the assembled cable hanging about a foot from the car I was able to use the torch to solder everything together, feeding solder into each side of the splice letting it wick down the wires into the hot copper tube.

When it cooled off I slid one piece of heat shrink tubing down and shrunk it on.  I did the same with the other piece to give it more insulation, the reason for this was b/c the OEM stuff was thicker than the stuff I was able to find.

Next I pulled the wire back through the firewall and got everything back together.

Hope thats it, it made a huge difference, no problems so far.  I didn't check to see if the joint heats up when the car is cranking over.  I've heard that the failing OEM joints can and even melt away their insulation, but mine hadn't.  Hopefully my splice isn't getting hot, I think it is robust enough to handle what is going through it.

----- Original Message ----
From: Brett Dikeman <brett at>
To: Nathan Winters <natewin at>
Cc: Kneale Brownson <knealeski at>; 200q20v at
Sent: Sunday, June 24, 2007 5:11:02 PM
Subject: Re: alternator acting up

On Jun 23, 2007, at 8:28 PM, Nathan Winters wrote:

> My car did the same thing, it was the cable from the starter/ 
> alternator to the battery.  It runs 2gauge from the battery to the  
> firewall, then down to 4 gauge through the firewall to the  
> starter / alternator.  The splice fails electrically and does  
> exactly what you describe.
> I cut the wire to the battery cable about 1 foot from the splice,  
> the wire was in good shape.  It then spiced in a piece of 2 or 0  
> gauge that I got from a stereo shop to the starter.

This is a well-known problem with type 44's.  How hard a job was  
this, and what was involved?  I'm facing a similar issue (along with  
a battery drain that is getting *very* tiresome.)

A writeup from someone who has done this before would be helpful.  I  
don't have the time or money to rip up the entire cable, so a splice  
sounds nice.  In particular, I'd like to know how you did the splice  
(longevity is obviously a bit of a concern), whether you ran new wire  
to the fuse/relay boxes, etc.


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