Battery maintenance is not something that is done very often by me.
Until one day I decided to check the battery fluid levels. I read
somewhere that battery levels can diminish quite rapidly.
When taking the filler caps off, checking at the front was not
a problem, but the others were. Due to the overhang of the
engine compartment fittings, It is not possible to see the filler
hole levels at the back. I came up with this solution, which is
probably familiar to most people.
Using Distilled battery water from a Motor factor, not tap water.
With a flexible extension pipe battery filler - I made up a plastic
bottle. Fill the back cell first, until you see the fluid just
overflowing, empty the filler, squeeze the bellows, allow the bottle
to suck up the surplus, then empty it into the second from the end
filler hole. Do the same with each cell aperture.
Try not to allow the water to overflow as it has an acid content and
will soon show up on the battery tray, and cross member, by rusting.
A Battery Filler, part Ref: 14900, can be obtained from: Vehicle
Wiring Products, complete address below.
Checking the battery. Start the engine, with your test meter. The
battery voltage should increase slightly from a nominal 12.5 v fully
charged battery, when the engine is idling, and depending on the load
on the battery. As the revs are increased then the voltage reading
will rise up to a maximum of around 14.5 volts, if the alternator is
operating correctly. Over 14.5 volts or a fluctuation in voltage at
steady revs above idle, indicate a faulty voltage regulator in the alternator.
The Alternator
A simple way of testing this alternator function without a voltmeter
is to watch the brightness of the interior reading lamp betwen idle
and around 2000 rpm. It should brighten as the battery voltage
increases when the alternator is producing a charge current.
A fully charged, healthy battery with no load (headlights on, etc.)
will still be trickled charged and showing around 13v about 0.5v
above nominal battery voltage when engine is ticking over.
Many thanks for this information which came from: "Alan
Eccles" <alaneccles54[at]hotmail.com>
I have included below for the interest of the DIY mechanic, details
of the Alternator. Connectors can be seen on the drawing 'Alternator
Contacts' and the internal workings can be seen in the drawing
'Alternator contacts Internally'
On the B+ contact can be found the heavy cable to the battery,
usually covered in RED insulation. Often there is also a heavy cable
to the starter motor at this point.
The D+ cable, in the Boxer covered with a BLUE insulation, is the
cable which is used for the Fridge voltage control when the vehicle
is running.
The W contact is used for Tachometer Meter functions.
[Click For a larger image.]
