Date: Mon, 2 Jun 2008 11:05:58 -0700
Reply-To: Scott Foss - Shazam <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Foss - Shazam <scottdaniel@TURBOVANS.COM>
Subject: Re: On the topic of Battery explosion/voltage reg Batt &
Charging Discussion by SDF
In-Reply-To: <48bd05410806012124r38778545od54b61f5cc5097ec@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
The FIRST THING ............for anyone that wants to have 'any' smarts
about what is going on with alternator/voltage regulator.......
you just, and MUST, simply check the charging voltage at the battery
with the engine running.
( dim or intermittent light is likely low or no charging in anything.
There is NO over-charging warning indication on the van - though a
standard and simple volt-meter on the dash would be a solution for that.
Serious over-charging is, however, pretty rare. very, very rare actually.)
But...........here's how to test it according to Scott Daniel Foss,
Turbovans
( Digital Voltmeter is best for this, analogue will do, but not as nicely )
1. Read the 'resting voltage' of the ( starting or main ) Battery.
Expect 12 something volts. I think 12.7 is considered 'fully charged.
What is actually is isn't that important as long as it cranks nicely
on the starter and fires up and runs.
2. Start the engine, let it idle.......
Normal 'ok' is 13.8 volts. I consider this lowish- but that's what
many Bosch Vanagon alternators/volt. regs are set at. Alternators have
quitet good output at low rpm ( it turns faster than engine speed you
might notice, looking at the relative pulley sizes ) . It should read
the same at idle as at 2,000 rpm.
The highest 'good normal OK ' reading is 14.5 volts.
., BTW, I install solid state adjustable voltage regulators ( it
includes the brushes too btw ) sometimes...........I set those at 14.5
volts. This is a big advantage on a diesel, since diesels are missing a
'real' ignition system ( not counting the glow plugs ) and starter
cranking speed helps develop enough compression to make enough heat to
ignite the diesel fuel.......
so higher charging voltage can help a tired diesel engine. - For
gasoline it doesn't matter so much. Oh, you get brighter head lights
though.
Any charging voltage about 14.5 or so......too high. 15 or 16 volts -
bad news, not ok. Fwiw, one alternator rebuilder guy i know sets his at
14.7 volts.
Bottom line, look for 13.8 volts min, 14.5 volts max.
3. with engine idling, watch the volt meter as you turn on the lights.
Charging voltage should hold the same with lights on, or drop 0.1 volts
at the most. Typically on a stock waterboxer vanagon I'll see 13.8
volts at idle, lights off or on.
so start there - CHECK CHARGING VOLTAGE AT THE BATTERY.
other IMPORTANT minor things -
1. You can have fine charging voltage and a not-working warning light in
the dash.
2. Many people are running around with non-functioning oil or batt.
warinng lights and they are totally unaware of it.
YOU ARE NOT SUPPOSED TO TURN THE KEY FROM 'OFF' STRAIGHT TO 'START' !
- RTFM - you get in the van, you turn the key to 'On' - you observe
that 3 warning lights are functioning - oil, batt, and flashing water
temp, THEN you start the engine, and observe that the 3 warning lights
all go off. - the flashing water temp LED takes a few seconds to go off.
IF YOU JUST HOP IN, HIT 'START' ........YOU HAVE * NO IDEA * that the
warning lights are actually working !
How often grounds and connections are not thought of, can not be overstated.
Everyone is used to thinking about the power supply side of circuits
only. The return or ground path side is at least as important.
Always clean and tighten all grounds.
Three things need to be grounded to each other - the Neg Battery
terminal, the engine and transmission , and the van's body.
Water level in the battery - never over fill ! Acid will just come out
and ruin things. The rule is : If they plates are covered, don't add water.
Letting any lead-acid battery sit discharged - does permanent damage to it.
Battery charger , plug in 110 volt - type. You really need one to work
on cars. You need 10 amp min, and it MUST have a meter on it.
because- if you have an old or dead or used battery that's discharged -
if the needle won't jump up when you connnect the batt. charger - it's
most likely a dead and useless battery.
Mini-hydrometer- these cost about 1.90 at Shcuck's Auto - you take a
hydrometer reading of each cell. this is how you identify a weak or
dead cell in a lead acid battery. you are able to compare the condition
of each of the 6 cells.
My advice is do not even consider getting a battery on which you can not
take a cover off and see inside each cell, to add water or whatever.
So far i see no reason for Optima batteries, do not think they are
'better' than a conventional lead acid starting type battery.
But the very best battery you can.
For late Vanagons,. subaruvanagons etc. I get a Group 41 I think it
is...............the right terminal locations, the right hold-down
system - and 900 Cold Cranking Amps. That is one strong starting
battery. They cost 90 bucks, but with care -last years and years and years.
enogh for now !
signing off, Scott
www.turbovans.com
Brendan Slevin wrote:
> Ok, this has me nervous now. My battery light on the dash is on a bit most
> of the time. Well, not all the time. I start the van (never any problem
> charging) and the light is off but as soon as i rev the engine it comes on
> and fades in and out--corresponding to engine speed, fast engine=fast fade
> in and out, slow engine=slow light. Anyway, I've always suspected the
> voltage regulator but never knew this could result form me just learning to
> "live with it." Please inform me on what to do!
>
> Brendan Slevin
> 84 GL Totoro
> Bend, Oregon
>
>
>
> On Sat, May 31, 2008 at 7:00 PM, Zoltan Kuthy <zolo@foxinternet.net> wrote:
>
>
>> Just as I turned the key, booom, smoke and chaos.
>> Apparently, the battery exploded under the pass. seat. One cell leaked out
>> completely, the others partially. The plastic of the battery fell apart at
>> places.
>> Today, I was cleaning the whole thing up, POR 15, bedliner spray, cleaning
>> ground, fitting with stainless bolt.
>> Otherwise all is well.
>> Zoltan
>>
>>
>
>
>
