Difference between revisions of "VW Electrics main cables"

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==Cable corrosion==
==Cable corrosion==


The photo below shows the terrible (although not untypical) state of a cable at the rear of an alternator. Most alternator connections actually terminate in a plug rather than like this and therefore the state of them can easily be missed. The copper within either starter or alternator cable can become brittle and corroded, no matter how far you cut back, and potentially create resistance  - reducing the alternator's ability to charge and the starter's ability to turn the engine over.
The photo below shows the terrible (although not untypical) state of a cable at the rear of an alternator. This is acid corrosion which can also cause the insulation to crack and break away leaving bare copper wire. Most alternator connections actually terminate in a plug rather than like this and therefore the state of them can easily be missed. The copper within either starter or alternator cable can become brittle and corroded, no matter how far you cut back, and potentially create resistance  - reducing the alternator's ability to charge and the starter's ability to turn the engine over. The stands can break too, further reducing the capacity of the cable.  


The vehicle is a 1.9DG and wiring layouts do vary.
Generally, when things have become this bad, the only thing you can do is replace the cables completely and solder new connectors as and where required. You can crimp (if you have access to oversized crimps) but soldering makes for a more reliable connection and helps seal the cable.
 
[[File:cab1x.jpg]]
 
This particular engine a 1.9DG and wiring layouts do vary. It also uses a golf alternator rather than a stock one so only has a single nut which holds the main cable. You will need to decide how best to replace corroded cables in your setup.  


Generally, when things have become this bad though, the only thing you can do is replace the cables completely and solder new connectors as required. You can crimp (if you have access to oversized crimps) but soldering makes for a more reliable connection and helps seal the cable.


[[File:cab1x.jpg]]
==Replacing cables==


This particular engine uses a golf alternator and only has a single nut which holds the main cable. I removed the old corroded cable which had been twisted around the post and clamped between two washers (not by me!!) and replaced it with new, thicker cable, and soldered ring connector on the end (see photos below).
I started by removing the old corroded cable on the alternator which had been twisted around the post and clamped between two washers (not by me!!). I replaced it with new, thicker cable, and soldered ring connector on the end (see photos below). The other end of the cable didn't (as I expected) terminate at the starter. It went to


The vehicle is a 1.9DG and wiring layouts do vary.  
The vehicle is a 1.9DG and wiring layouts do vary.  

Revision as of 12:56, 31 May 2014

Introduction - Good Connections

(Under construction)

Intro by Covkid:

Good connections and good cable are essential for effective charging and starting. However, after 30 years work, the main heavy-guage cables that go from alternator to starter and battery can be subject to deterioration. You need at least 4 metres of new cable do this job - suggested types at the end.

The thickest cable by far is the one between the battery and starter and if you drive a T25 with your main battery behind the drivers seat, you'll realise that its quite a distance between the two. The alternator cable isn't quite as chunky but for this upgrade I replaced both of these cables with the same 25mm fine strand cable. Its just about bendable at that thickness.

Cable corrosion

The photo below shows the terrible (although not untypical) state of a cable at the rear of an alternator. This is acid corrosion which can also cause the insulation to crack and break away leaving bare copper wire. Most alternator connections actually terminate in a plug rather than like this and therefore the state of them can easily be missed. The copper within either starter or alternator cable can become brittle and corroded, no matter how far you cut back, and potentially create resistance - reducing the alternator's ability to charge and the starter's ability to turn the engine over. The stands can break too, further reducing the capacity of the cable.

Generally, when things have become this bad, the only thing you can do is replace the cables completely and solder new connectors as and where required. You can crimp (if you have access to oversized crimps) but soldering makes for a more reliable connection and helps seal the cable.

Cab1x.jpg

This particular engine a 1.9DG and wiring layouts do vary. It also uses a golf alternator rather than a stock one so only has a single nut which holds the main cable. You will need to decide how best to replace corroded cables in your setup.


Replacing cables

I started by removing the old corroded cable on the alternator which had been twisted around the post and clamped between two washers (not by me!!). I replaced it with new, thicker cable, and soldered ring connector on the end (see photos below). The other end of the cable didn't (as I expected) terminate at the starter. It went to

The vehicle is a 1.9DG and wiring layouts do vary.

Cab2x.jpg


Ringterm1a.jpg