Handy tip to get the best out of the A127 alt

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lynall

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Ever since I fitted a volt gauge Ive not been happy with the battery voltage especially when all lights/fan/heated seat were on and if electric fan on voltage dropped below 13 volts which is no good to anybody.
So after loads of research I found about battery sensed alternators and found how to convert the A127 to battery sensed, basically no matter what you turn on, the new brush box compensates for it and it now runs 14.1 volts at all times even with every thing turned on.
So you need one of these
ALTERNATOR REGULATOR TO FIT A127 LUCAS MAGNETI MARELLI TRACTOR AGRICULTURAL | eBay
Fit it, then cut off the tab on the orange wire, extend and run the wire to the battery positive, BUT before you connect it up fit a 220ohm resistor between the wire and the positive terminal and voila done.
Resistors 10 x 220 Ohm 0.25w Carbon Resistors 1/4w Resistor 220R | eBay
Two week so far in my 200 90 and Im very pleased, such a simple and worthwhile mod.
 
Three screws, stubby philips cross head, NOT a pozi driver as they dont grip.
Remove the screws very gently wiggle the reg pack out, not to far and you will see a white wire with a black plug, this just pulls off and thats it you are out.
Opposite to refit, DO NOT force it in! gently coax the reg pack in after connecting the white wire of course! if it feels wrong remove it and check the brushes are still okay, then cut off the tab on the end of the wire with the reg pack and extend it back to the battery along the top of the chassis rail, allow some slack engine end to allow for movement, I used heat shrink crimp connectors as they are waterproof
It sounds complicated but in reality its a piece of ****

Mines still fine just over 14 volts at all times, thats with lights, heated seats and heater fan switched on
The same mod I have also done on the series tdi and that also been fine, but runs at 13.8 all the time, why I havent a clue?
 
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