Conference vicki::boats

    
    Place a volt meter on the battery and take the boat out for a spin.
    With the motor off the battery should read between 12.5 and 13.5 volts.
    Start up the motor and rev up to 3500 RPMs. The voltage should now
    read ~14.5 volts. If the voltage does not change then there is no
    charge being produced by the alternator.
    
    There are two areas to check on a modern 115, the stator ring and the 
    solid-state AC/DC converter (can't remember the technical name for it).
    Both are tested with an ohm meter. The stator ring should read zero
    resistence. Most converters have three wires on it and need to be tested
    to manufactures specs. Most times a shorted converter is the reason
    for a non-charging state.
    
    Sounds like your battery had a failure of some type. Hopefully the
    charging system is still in working order.
    
    Good luck,
    
    Doug.
    
    

I can't tell you if it was the battery or the alternator.  However, if you
COMPLETELY discharge the battery, for instance forget to turn off the radio
and the next time you use the boat is the following weekend,  the battery will
never take a charge (ie: battery always pulls 4-6 amps no matter how long you
charge it). 

    Last season, I bought a Radio Shack pocket sized digital multimeter to
    keep tabs on the state of charge of my boat's battery. You can see the
    voltage rise and fall with the state of the charge very easily.
    
    Right now (or a few days ago) they were on sale - for $16.95, I believe.
    
    Bill

    Thanks for the input.  I will look as .1 stated.  I won't get to do
    this till next week for I have to go to Padre Island and sun and fun
    for four days.  Check ya later,
    
    Glenn

    A convenient way to monitor battery state is to get a "battery
    condition monitor".  Unlike most things involved in boating, they are
    cheap.  It's a voltage sensor, but only shows three readings.
    
    You get a little box with three LEDs on it.  Leave it attached.
    	green => battery good condition
    	yellow=> battery medium condition
    	red   => battery failing.
    
    Mine cost me about $13 but you'll find them even cheaper if you visit a
    caravan dealer.  They're quite popular for caravanners.  Cheers - Ken.
                                                                 

    Should you always remove the motor leads before using a mains voltage
    charger on the battery or can the battery be charged (topped-up) where
    it is with leads still attached?

    Sorry it took so long to get back to this note.  As stated, I took old
    battery back and got a new one.  I put it in and it is working OK.  I
    keep a trickle-charger on it everynight to cover my A$$.  It seems to
    be doing OK.  After talking to a buddy in the office, he thinks I might
    have purchased the *WRONG* type of battery.  The battery was the
    biggest marine battery K-MART had.  It has the words continous-use on
    it.  He tried to tell me this type of battery is for devices like
    trolling motors, which would pull minimum amounts of drain for long
    periods of time.  He claims that I need to get another type of battery. 
    Any comments on this??  Boat dumb you might say!!
    
    Thanks,
    
    Glenn

    I would be interested to know what the difference is between a deep
    cycle battery and a continuous use battery.  They sound pretty much the
    same to me.
    
    Jeff
    

<    I would be interested to know what the difference is between a deep
<    cycle battery and a continuous use battery.  They sound pretty much the
<    same to me.

   I too believe a "deep cycle" and "continuous use" battery are probably the
same thing.  In re-reading .0 though it sounded like the "deep cycle" battery
was being used to "crank" the engine.  The battery I use for my trolling
motor is not the same as the one I have supplying the starter (cranking) on my
outboard.

   One battery is designed for long slow discharge giving me a few AMPS for 
hours at a time (between recharging), whereas the "cranking" battery is 
designed to give me lots of AMPS for a very short period of time (i.e. the 
time it takes me to start my engine) after which my alternator will start 
recharging it in preparation for the next high current use. 

   I don't know what, if any, reduction in life expectancy you might experience
by using a "deep cycle" battery as a "cranking" battery, but it doesn't sound
like the right tool for the job to me.

FWIW,

Al

An automotive battery is designed to supply a large current for a very 
short time, eg, starting an engine. A deep-cycle battery is designed to 
survive many, many very nearly complete discharge-recharge cycles. Most 
automotive batteries will fail after just a few (less than 10 perhaps) 
nearly complete discharges. Deep-cycle batteries are quite capable of 
starting even large engines, and suffer no harmful consequences when so 
used. If you only use your batteries for engine starting, then 
automotive batteries are fine. If you use your batteries for long 
periods before recharging (as is the case for most sailors -- we've gone 
as long as three days without running the engine), then deep-cycle
batteries are essential. 

================================================================================
           <<< MSCSSE::SYS$SYSDEVICE:[NOTES$LIBRARY]SAILING.NOTE;2 >>>
                                  -< SAILING >-
================================================================================
Note 843.23                       Battery Size                          23 of 28
MSCSSE::BERENS "Alan Berens"                         52 lines  25-MAR-1991 12:57
                              -< engine starting >-
--------------------------------------------------------------------------------
A recent entry in SAILING made the comment:

  And the second advantage [of automobile batteries] is: they are designed 
  to start an engine.

The implication of this statement is that deep-cycle marine batteries 
are not suitable for engine starting. I disagree. I think deep-cycle 
marine batteries are quite suitable for engine starting in the sailboats 
most of us can afford to own. 

Automotive batteries must be capable of supplying sufficient current to 
start an engine in very cold weather (eg, at least 0 deg F). As we all 
know, the current that a battery can supply decreases rapidly with 
decreasing temperature and the power required to turn an engine 
increases with decreasing temperature. Thus an automotive battery is 
designed to produce a large current even at low temperatures. Some of 
the design features that enable large currents to be drawn (eg, thin
plates) are features that are not desirable in deep-cycle batteries. 

A standard specification of batteries is cold-cranking amperes, ie, the 
number of amperes a battery can supply for 30 seconds at 0 deg F without 
the battery voltage falling below 7.2 volts. A typical 105 amp-hr 
conventional deep-cycle battery has a cold-cranking ampere (CCA) output 
of 530 amperes. A similar-sized Prevailer deep-cycle gel battery has a 
CCA output of 700 amperes. Both of these batteries will certainly supply 
more amperes at higher temperatures. (I've never had to start our diesel 
at a temperature below 40 deg F while sailing.) 

How much current does a starter motor draw? Most engine service manuals 
don't say, but it appears that (from a Ford heavy-duty truck manual and 
a VW Golf manual) the typical starter motor running current is 200 to 
300 amperes and that stall current is perhaps 500 amperes. These numbers
are for engines ranging from a 1600 cc diesel to a 9200 cc heavy-duty
truck gasoline engine. Thus is would seem that, at least at temperatures
above freezing, a deep-cycle battery would be more than capable of
starting a small marine diesel engine. In fact, we've been starting our
1600 cc diesel with only deep-cycle batteries for eleven years. If the
batteries are rather discharged, it has been necessary to use two in
parallel, but this would be true of automotive batteries as well.
Interestingly enough, by the way, the intermittant maximum current
rating (ie, for engine starting) of battery selector switches is in the
range of 325 (Cole Hersee) to 360 (Perko) amperes. 

While it is true that battery manufacturers would like us to buy 
expensive deep-cycle batteries, the fact that every published reference 
I have seen (including Practical Sailor) recommends against automotive 
batteries persuades me that deep-cycle batteries are the only ones to 
have on my boat. 

Of course, your opinions and choice may be different.

Alan

    To further support Alan's point, i have a pair of Chrysler 360
    blocks. I have 5 batteries, 2 are 6 volt 3 are 12 volt, they
    are all deep cycle.  The 2 6 volt are house batteries, running
    lights etc. the 12"s are reserved for starting, however at times
    i have had to call on the pair of 6 volt batteries for starting.
    
    the bottom line is that a deep cyle is the best choice, they seem
    to tolerate more abuse, even for starting...
    
    JIm.

    Another case in point for deep cycle batteries for starting. I am a
    volunteer EMT with the Epsom Rescue Squad. If you want to see a 
    severe 12 volt electrical environmnet, look at an ambulance. In
    addition to lots of outside lights and warning signals, we have an 
    electrical air-conditioner for the patient compartment, and lots of
    electrical and electronic equipment inside. This is an environment
    where battery failure is unacceptable. All of the ambulance services
    around us, including ours have a pair of big marine deep cycle 
    batteries that do it all, including starting. They have proven to
    be much more reliable under stress. Even top quality automotive
    type batteries die prematurely after a few deep discharge cycles.
    
    Bill
    

    Anyone know anything about an Interstate "booster battery"?  It's a
    battery made by a company called Interstate.  Interstate is a company
    that may be specific to my geography.... I'm not sure, The Washington D.C.
    Metropolitan area.  The battery, which comes in both marine and automotive
    flavors, has a switch on top of it.  The switch, being more like a dial
    that can be rotated, has two positions, normal and boost.  Supposedly,
    when the battery gets drained, you can flip it over to boost, and start
    the motor.

    Anyone seen anything like this before? Are they any good? My marine
    dealer, who I'm in the process of purchasing a boat from is pushing
    this new type of battery....

    Thanks,
    Matt
       

    Sears also sells the "booster" battery at a very signifigant premium.
    
    For a boat, I would opt fo0r dual batteries and a transfer switch- this
    way your "backup" is a full size, high capacity battery, not the
    miniscule equivalent of a lawn tractor battery that the "booster "
    represents.
    
     I also don't beleive that these are available in the deep cycle marine
    batteries.
    
    Dick

    Interstate is one of the major battery manufacturers. I regularly see
    their trucks on the highway. I believe they have a quality reputation.
    
    Bill
    

    Besides selling under their own name, they make a large number of the
    batteries sold under other companies names.  They are very big in the
    commercial world making batteries for electric fork trucks, ect.  They
    make a good product.
    Wayne

    Interstate is common in Me, N.H. Mass. Areas.  They have an excellent
    reputation. I used Interstate (engine starting batteries) for years
    with no premature problems.  An EXCELLENT marine battery which is made
    in N.H. is SURRETTE. They have been around for at least 30 years. 
    Many commercial marine people use Surrette.  I have a Surretee deep
    cycle in my camper and I havn't had any problem with it... but I have
    only had it two years.  I expect 10 years out of it. 
    
    I use a deep cycle on my 25 hp Johnson equipped boat. The outboard has
    no alternator so I go for a week plus at a time between recharges. The
    deep cycle has no problem starting the outboard.
    
    Jeff G. 
    

    The title of this note "Battery or Alternator" describes my question
    perfectly.(therefore, Mr. Moderator, there's not need to move this
    note :-) )

    The Nautique is still on it's original 1987 battery and it's OEM
    alternator. The boat is a 351 ci, PCM straight inboard. The boat
    still starts and runs fine. I've noticed that heavy electrical loads
    (lights, radio & blower combined) cause the voltmeter to drop below
    12 volts. Is this indicative of impending battery or alternator
    failure? I assume this is not a case of my "just not noticing" before,
    since I believe automotive systems are supposed to be above 12 volts
    all the time... correct?

    Recent history: Battery was "successfully" charged in March. (Means
    I asked the guy charging it if it displayed any signs of deterioration
    and he, in his best technical jargon, said "no"). Alternator belt
    has proper tension.

    Is there really a problem on the horizon? Is there a definitive test
    for batteries vs. charging system?

    Thanks,

    Rick

    Rick - Generally, if the voltage drops too low on heavy loads
    especially at low engine speeds, it is the battery at fault. At low
    speeds, the alternator does not put out as much as at high speeds. So
    during heavy load, the battery has to make up the difference. If the
    battery is getting weak, it doesn't 'make it up' as well and so the
    voltage drops lower than normal. If you boat starts well, it would be
    hard to notice a battery that is getting bad until it gets real bad.
    
    					Kenny

re               <<< Note 843.19 by KAHALA::SUTER "Never too Hot!" >>>
>                  -< 6 years on 1 Battery, time for a new 1? >-

	Tempting, very tempting....  OK, I'll pass up a "tasteless 
	comment"  opportunity  {requ'd policy anyway}  (-:

	If your SN is wired the same way my SN is wired you may only 
be seeing the voltage drop from the battery to the panel - 
alternatively you may have a slightly dirty terminal and could be 
losing thousands of microvolts there.   Here's a little diagnostic;  
do the other guages ("gages" ?) change their opinions when you switch 
on the blower at idle ?   e.g. does the oil pressure reading increase ?

	Reg	{SN doctor;  makes house, lake and river calls}

    
    If the other guages don't change their mind (as reg says)
    
    then from my own experience theres just a load on the system
    
    and the volt meter is reflecting it.  BUT if the others change
    
    their mind, there's another problem. It could be a battery
    
    even a loose belt.
    
    Let us know,
    
    JIm

    If you look at the instruction sheet with the Guest "Smart Switch"
    (don't have to buy one...just browse in the store), they have a very
    good description of the critical voltage points on a battery. I recall
    that 11.7V is "not enough to start" while 12.6V is "normal".
    
    Also, while running, you aren't supposed to be using the battery anyway
    but should be running entirely off the altenator (unless the alternator
    is not putting out sufficient energy).
    
    Batteries are cheap...REAL cheap if you've ever been stranded overnight
    due to a dead battery. I just replaced a single DELCO Voyager deep
    cycle (after only 1 season's use) with 2 960CCA deep cycle batteries
    and a Guest Smart Switch. You should check the battery with a voltmeter
    rather than rely on a dash guage.

	Further explanation:

	CorrectCraft (and probably others) run the +'ve feed wire up
to the panel; it goes to the "ignition" circuit breaker and the
breakers for other circuits that don't require ignition.  The
"ignition" circuit breaker feeds the ignition switch (kinda obvious)
which in turn feeds the other circuit breakers and the "instruments"
(non musical). Ideally the voltmeter would have a separate wire
running to the battery +'ve terminal, i.e. it would sense BATTERY
terminal voltage.  In this less than ideal world the manufacturers
save a few feet of wire and maybe a connector or two by wiring the
voltmeter to the hot side of the panel circuit breakers, so whatever
voltage drop there is along the hot feed, through the ignition switch
and through the "ignition" circuit breaker - gets subtracted from
battery terminal voltage.  The more current you draw (power seats,
etc.) the greater the voltage drop, even if the battery/alternator
team are doing a fine job (ask Charlie Ohm).  Also, any increase in
impedance along this path will cause more voltage drop - but won't
affect the ability of the battery to turn the engine over. 

	So, if its spinning the engine OK my guess is that you're just 
witnessing Ohm's law in action.

	Reg

    
    	I guess I am witnessing Charlie's law... (who the hell is
    Charlie)..?
    
    	Cuz, I managed to get out for a couple of hours last night
    (na na na na na na!) and any dash switch (lights, blower, power
    seats?) would make all the other switches jump and/or change.
    
    	I'm still a little concerned as the "no accessory" voltmeter
    setting is 12.n where n is 6 to 9 and the "all accessory" voltmeter
    setting is 10.n-11.x where x is 0 to 5.
    
    	I'll keep an eye on it, and of course it wouldn't be the first
    thing that it took me seven years to notice! :-)
    
    Rick
    
    BTW: I have more gas (by the guage) with the lights ON!

    
    ????  who has power seats in the boat.....
    
    
    Rick, you do.............(:)  
    
    
    
    and a shower..............
    
    JIm

>>    BTW: I have more gas (by the guage) with the lights ON!
    
    So that night you ran outa gas and we had to paddle to shore, all you
    had to do is flip the lights on !??!
    
    ~jeff

    This maybe related, then again, maybe not.  The temp, gas, and oil
    level gauges in my truck would occasionally peg.  Turns out I had
    a frayed ground cable to the battery that would sometimes dis-connect.
    The engine would keep running off of the alternator.
    Wayne

re               <<< Note 843.19 by KAHALA::SUTER "Never too Hot!" >>>
>                  -< 6 years on 1 Battery, time for a new 1? >-


>    The title of this note "Battery or Alternator" describes my question
>    perfectly.(therefore, Mr. Moderator, there's not need to move this
>    note :-) )

	Good news / bad news  time.....  which would you like first ?  (-:

	OK, lets start with the good news, try this for an answer;

		"Probably neither".


	Now the bad news, its most likely;  



		"Correct Craft"


	For quite a while now I've been meaning to figure out why
pressing the horn button sent all the guage readings to "nonsense" -
especially the voltmeter, which indicated about a 4 volt drop.  There
wasn't much noise from the horn either.  I checked the wiring, found
there to be NO horn relay (a big disappointment), so I opened up the
box that the horns live in.  I found a broken mounting bracket and a
couple of horns that had quite a lot of dirty water in them. Catalogue
prices for  "Marine horns" (sic) start at around $24 each.  I figured
that car horns probably suffer more salt water than my boat ever will,
so I got a pair of generic auto horns from the local NAPA outlet for
$26.  I checked each of them directly across the battery, mounted them
to the base of the box they were to live in, wired them up and checked
them across the battery again - not a bad hi/lo sound together. 
I reassembled the box, caulked all the seams, etc., wired the horns to
the switch - then they wouldn't work, same symptoms as the old ones -
SH*T !  Maybe it wasn't a  "Horn"  problem ???? 

	It didn't take me long to figure out that a jumper wire from
the battery +'ve terminal DIRECTLY to the horn switch would eliminate
suspicion about the impedance of the path from the battery and
alternator.  That didn't improve things, even going directly to the
horn wires didn't help, so it  "HAD TO BE"  on the ground (-'ve) side.
I have rarely had good luck chasing ground problems (except at dec, in
a field service role).   Anyhow, a jumper from the battery -'ve
terminal to the ground side of the voltmeter appeared to fix
everything - so I started chasing it back as a poor ground.  Unlike
trucks and cars (and some computers) fibreglass boats don't have a
chassis ground.  The horn ground path on my Nautique goes
approximately as follows; 

	Battery -'ve terminal 
	Engine block, near the starter
	Engine intake manifold, right side rear
->	Connector in engine compartment - 
	Harness to dash
->	Large connector under dash (black rubber)
	dash right side harness 
	a 6/7 way bundled crimp and distribution to the dash panel 
		indicators that go with the circuit breakers
->	smaller connector (black rubber)
	harness to left side of dash
->	small connector (white nylon/plastic)
	splits to horn and radio

	If you suspect a ground problem I suggest one of the first 
things to try is to spray in some contact cleaner at the connections 
marked -> above.  BTW, the supply (+'ve) side follows most of this 
path too, so cleaning up all these connectors is generally good for 
your electrical system (-:

	NOTE:  I ain't happy with this design,  a high current device 
such as a horn, shouldn't be this far down stream (pun)  on relatively 
puny wiring - I'm considering a horn relay,,,,,  just considering it.

	Reg

    Contact cleaner? What, where and how much? 
    
    Bruce

I use TV tuner cleaner.  It comes in a spray can a couple bucks at Radio Shack.

Gordon

re                       <<< Note 843.31 by BLUEFN::GORDON >>>
>                             -< TV tuner cleaner >-

	right,  same thing (more or less).

	I think  "LPS"  is/was a generic name in the pre-chloro_flouro 
awareness daze.  Almost any cleaner/solvent will do the job, in fact 
just opening the connectors and closing them again probably "wipes" 
the surfaces.

	Reg

re: .29

The old Boston Whaler philosophy was to keep everything out in the open
where it would be easy to fix. That included a connector back by the
engine, where the trim & tilt wires could be disconnected. Well, being in
the open also meant being exposed to the elements. Since I did a lot of
salt water boating, that exposed connector caused me to lose trim & tilt
a couple of times (when I really needed it) due to corrosion.

I permanently fixed it in 1982 by essentially potting the whole connector
in "Liquid LectriTape" (spelling could be off), after cleaning out all
the green stuff and making the contacts bright and shiny. I made up the
connector, then glopped on the lectritape(?); I let it set up, then I
glopped it up again. It ended up looking like a molded connection. If
necessary, a penknife could separate it. But I never had trouble with it
again, and the next owner is still using it without problem.  

Art

    LPS is a brand name; there is LPS-1, LPS-2, etc., each one has a
    different purpose, ie; LPS-1 might be like WD-40, LPS-2 might be more
    like Marvel Mystery Oil, LPS-3 a water repellent, etc.  
    
    Carl