Land Rover Repair: Alternators, heavy duty battery, raison d etre

Question
I've gone through 3 alternators in the last year (all rebuilds) battery has been replaced once. Any suggestion as to what could be causing the alternators to burn out?  Veh is '98 Discovery, no aftermarket accessories

Answer
Hello James:

you and me both!   I too have installed 3 alts in my Disco.  After much discussion and internet research, I have concluded that the alt designed for our Disco's is severely overloaded.   Most owners with the same problem will tell you that the best long-term solution is a heavy duty battery + alt replacement.  My last alt replacement was done in conjunction with a new battery (Interstate), so far, so good.

I suspect that the moment the battery begins to wane the alt is subject to failure.  The close relationship between the alt and battery probably initiates the alt failure.  If your battery loses a plate or falls below the deep cycle point, I am convinced it puts a larger burden upon an already overloaded alt.

Poor electrical design is the suggested source of the problem.  The alt's "raison d'etre" is to charge the battery.  So buy the best battery you can to avoid a $800 alt purchase OEM or a $350 rebuilt.

Best of luck,

JohnMc