Re: [alfa] QV Battery Drain

["Dean W. Cains" <dwc@xxxxxx>]

Hi Steve:

Might not be a bad idea to hit Radio Shack for a $15-20 analog meter with a 
suitable amperage range.  I didn't know Alfa had a TSB specifically noting 
20mA as the acceptable drain, but that seems to be what both my Spider's 
('74 & '87) draw when resting.  The problem with your theory of guessing 
the current drain by the size of the spark is that mine both make pretty 
good sparks when I connect the negative battery terminal.  Using my ammeter 
on its 500mA range, I'll see the needle initially pegged past full scale, 
but after a second or two it settles down to 20 - 25mA.  What could be 
different between my Spider's and yours is that both of mine have 
electronic radios and alarm systems that could create that initial high 
current drain.  Those systems have memories that are maintained by the 
car's battery, and of course, the '87 also has the clock in the 
console.  That initial drain may just be from capacitors somewhere taking a 
charge.

As for the electrical system, in general on the later Spider's, it seems to 
have some weaknesses.  My '87 Veloce is identical to your Quad, 
electrically speaking, and I have made a several minor improvements that 
you might want to consider.  First, I replaced the original B+ cable from 
the (new, 75A) alternator to the power junction on the left inner fender 
with a larger gauge piece.  I used 8 ga. multi-stranded wire with new ring 
terminals soldered on both ends.  Second, I also ran another length of that 
same 8 ga. wire along the rear of the front crossmember to the B+ terminal 
on the starter.  Third, I installed an adjustable voltage regulator (from 
Vick Autosports) in the alternator, and set the output to 14.5v., whereas 
the original was only 13.8v.  Finally, I replaced both battery cables with 
ones slightly larger (2 ga.), and with better terminals.  Those things 
combined to make the ridiculous power windows almost acceptable, and I can 
drive at night without the dash gauge showing 11v.  I hear things are worse 
with a/c, which my Veloce lacks.  Now, the dash gauge reads around 12.5v at 
its lowest, which seems to be at least 1.6v lower than actual voltage read 
at the power junction on the inner fender or at the battery. I think Alfa 
(and Jaguar to mention another) designed the gauge to read 12v nominally 
because many people think 12v is correct.

Your idea of pulling the fuses to isolate an excessive drain, if you have 
one, is certainly valid, but it may just be that your battery is never 
achieving a full charge due to the inherent weaknesses in the system.  A 
fully charged battery should read 12.70 across its terminals, and a fully 
loaded alternator should put out at least 14.5v at 3000 rpm.

Regards,

Dean
Lutz, FL
'74 & '87 Spider Veloce's


At 02:43 PM 12/21/2003, you wrote:

> Date: Sun, 21 Dec 2003 10:38:30 -0800 (PST)
> From: Steve & Zita Waclo <z_waclo@domain.elided>
> Subject: [alfa] QV Battery Drain
>
> Hello:
>
> Have been lurking in the shadows since joining the
> group but thought it may be time to stop bugging Bob
> Rand all the time and tap into the collective
> consciousness. Appears to be a wealth of knowledge and
> information available.
>
> Just obtained an '87 QV a few weeks back and the issue
> of the day involves a battery that won't hold a charge
> more than about 10 days. It was installed 9/03. The
> weather is a bit nasty and I'm waiting for some parts
> and have been doing a lot of cleaning and inspecting,
> so the car has not been getting much run time. During
> infrequent road trips, the voltmeter takes a "key on"
> set at about 12 volts, then rises to perhaps 13V when
> the engine starts. When I re-charged the battery
> yesterday (and checked electrolyte levels - one cell
> needed distilled water), I noticed that re-attaching
> the positive terminal resulted in a small spark that
> may exceed the 20ma parasitic drain my Alfa TSB's
> refer to. My digital ammeter only goes to 20ma so I
> don't want to series it into the circuit for testing
> purposes. Plan to start de-bugging by pulling all
> fuses and watching for the spark to go away (I hope),
> then start putting them back in on at a time.
>
> Would appreciate any ideas on this situation and
> alternative methods of isolating the mystery load...if
> it even exists. Maybe 20ma makes a visible spark, but
> I think not.
>
> Thanks in advance for any ideas.
>
> Steve Waclo
> Carson City, NV
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