hey everyone -
well, maybe it's not so mysterious a problem. anyhow here i am posting again - you guys are usually the best with the advice.

i'm leaving in 2 days for a cross-country trip to san francisco and would like to figure out what might be up with my car. so here's the latest in the saga of my 87 manual volvo wagon:

car sat for about 5 days with no lights left on or anything, hadn't been driving it too much lately (was in new york city for a month) but it had been starting/driving just fine. i go to start it up and notice that the clock had stopped (uh oh!). sure enough no start, not even a click. pull out the digital voltmeter, pop the hood, and the battery was still there (you never know in nyc) and the meter gave me a flatline reading: 0 volts... call aaa to get a jump, and with car running, measured voltage across battery terminals (all following measurements made this way) to be 14.4v. good sign!

drove the car for a half hour, checked voltage across terminals again with car running, and this time it was at 13.3v, turned on lights and radio, dropped to 13.1v. seems a little low to me. anyways, stopped the car and the battery voltage dropped down to 12.0. also a little low for my liking. i'm thinking the battery can't hold a charge, as i'm not getting any warning lights going on in the dashboard which would indicate a problem with the alternator. (had the newer wiring harness put in almost 2 years ago.) so i unhook both battery cables and leave it sit overnight to make sure it's not draining from something else. next morning voltage is still at 12 volts... hmmm... curiouser and curiouser.

so, i'm thinking there is some sort of draw coming from somewhere? or could my battery be on it's way out (according to bentley, 12V is only 25% charge, but according to the sales guy at strauss discount auto supply, 12v batt is just fine.)? does this sound to anyone like an alternator problem? i am going to take it in to have the batt checked as well as the charging system, but i have a healthy mistrust of some mechanics, and don't want to buy an unnecessary alternator (which happened to me when i first got the car almost 3 years ago!)

ok, i've rambled on long enough. btw, the interstate 60 month battery is only 2.5 years old with about 7,000 miles on it. unfortunately i'm nowhere near where i got the original battery (chicago).

any advice much appreciated!
thanks in advance,
kathryn

Another point of view. I think you have a drain on your batt. Use your meter to see what current is being drawn with the engine off and on what circuit. Have you had problems with power door locks for eg.?

"measured voltage across battery terminals (all following measurements made this way) to be 14.4v. good sign!"
Yep. Proves charging system is working. 14.4V is on the upper end though expected if the battery needs recharging.

"this time it was at 13.3v, turned on lights and radio, dropped to 13.1v. seems a little low to me. anyways,"
Depending on temperature, voltage output varies. 13.3v is still charging. Note that as the engine was running, you were measuring alt. output and not batt ability. 13.1v just indicates current draw.

"stopped the car and the battery voltage dropped down to 12.0. also a little low for my liking."
It's a 12v battery. If it had dropped to 11v then there's a problem.

"i'm thinking the battery can't hold a charge, "
"i unhook both battery cables and leave it sit overnight to make sure it's not draining from something else. next morning voltage is still at 12 volts"
Obviously the batt is holding its charge (it didn't drop below 12v). Now if you were to leave it hooked up overnight and found voltage was down the next day, then you'd have a current draw.

So, I suggest you check for current draw, before you buy a new batt and find that it too leaves you stranded.
--
1980 245 Canadian B21A with SU carb and M46 trans

hey trevor-
thanks for your reply. i did a test for static current draw (i think i did it correctly? went according to the schematic in bentley) and it measured 0 amps on the voltmeter. measured between the negative battery post and the unhooked neg batt cable with the voltmeter set to read things in the 10A range. is there a different way to do this? my intuition says there is probably a draw somewhere and that the battery might also be a little weak. hadn't noticed anything funky with power locks, lights, anything...
thanks again-
k

I'm not much on newer Volvos but have been surviving battery problems for
50 years. There are a few common denominators.

1. Compared to most other types of equipment, automotive battery operating
voltages are low. This means that unnecessary resistance at ANY connection
has a big impact. In the starting circuit (the big battery cables and ground
straps) this is especially true. (in fact you could read "will not be tolerated".)

2. The lead alloys used for battery cable terminals and battery posts have
some interesting electrochemical properties in that under the right conditions,
they can form a very thin nonconductive film in a matter of seconds. Once on
my 164, in a very heavy rainstorm, it was cranking fine (but didn't start
immediately. 3 seconds later I turned the key again and it was graveyard dead.
It was pouring rain so I found someone to give me a ride home. An hour (and 2"
of rain) later, I went back to the car and tried again. Still dead. I'd
brought some tools so I raised the hood and disconnected the + battery cable.
The inside of it looked like someone had painted it white! I scraped it shiny,
brushed the battery post, hooked it back up and it started like new.
I know for a fact that this happened in between cranks, no more than 5 seconds.

Now 14.4 volts is a little high but might be OK for a battery that was really
dead, and should charge the battery to where it would start the car (but not
fully charged) in 10 minutes or less, assuming that the current is indeed
getting through the battery. Oxide films, loose or corroded terminals, etc
can prevent this. Also when you check the battery, check on the battery posts,
not the cable terminals. It may be substantially different. Also since lead
is an amphoteric metal (forms compounds characteristic of both metals and
nonmetals) under different conditions compounds may be formed that act as
diodes, so you could use the battery but not charge it, or vice versa.
Having the terminals clean and tight and keeping them dry will help avoid this.

Likewise 12.0 volts is a bit low. Usually when I check a charged battery it
will read about 12.6 and if under no load whatsoever it could read over 13 v.

When your charging system is working you should normally have 13.5-14 volts
measured at the battery posts and the same measured at the cable terminals.

Motor mounts, tranny mounts, suspension bushings, etc are all made out of rubber
or other nonconductive materials, so for both the CAR electrical system and the
ENGINE electrical system to work well together, you gotta have a good ground strap that connects the two. If yours is damaged, dirty or missing, this could
be part of the problem also.

While I am ranting and raving I might mention that the Interstate battery in my
122 wagon has sat for several weeks at a time lately but started right up when
I went to use the car. It was installed in 1998 and had a 60 month guarantee.
In fact once last winter it was buried in snow for a week. I dug my way into
it so that I could open the door, got in and it started in less than 2
revolutions of the engine, even with bad carbs.

I recommend Interstate. I know a little about the folks that make them and
they are good folks. The only Interstate battery that has given me problems
sat dead for several years and was frozen at least a dozen times while dead.
The guarantee expired during that time so I did not pursue the matter.
(It was also a 1998 60-month battery.) One thing about Interstate, they are
sold everywhere and their guarantee is honored on the basis of the installation
shown on the label. One thing I like to do is go to the shipping department
somewhere and get a plastic "shipping documents" envelope that sticks onto a
package sealed shut. Put the warranty papers for the battery in it and stick
it to the side of the battery, sealed shut. The plastic envelope will protect
the papers from chemical attack (as long as you don't poke a hole in it.) That
way, if you need the warranty, it is with the battery.

I'd further recommend that if you know you are going to be gone for a while,
either get someone to drive your car once a week or disconnect the battery.
IPD sells a switch that goes between the battery post and the cable terminal
to do this without actually taking the cable off or using tools. I haven't had
one of these, but knowing IPD, I assume they are good.

Parts and auto supply stores sell a brush gizmo with two wire brushes in it.
One end will clean the battery post and the other end will clean the inside
of the battery cable terminal. These seem to work pretty well. Also they
sell a pair of felt washers, one red and one black, that inhibit corrosion on
the terminals. These are not completely foolproof but they seem to help. Be
sure and put them on the right terminals (red = positive) because the chemistry
is different at the two posts.

In summary, get a new battery and make sure all the connections are clean and
tight. Make sure that your charging system is doing what it is supposed to do
(13.5-14 volts). Be sure that your battery is one that has NATIONAL guarantee
service. When you need help you can't go back where you bought it!
--
George Downs, Bartlesville, Oklahoma, Central US

Excellent post George! Thanks for the info.

Bean
--
'80 242GT 92k, '94 945T 123k

um correct me if i am wrong, anyone. the big deal about an Interstate battery is that it has a nationwide warranty, and any Interstate dealer should handle the warrany process.

When it comes to batteries... i have seen them do some wierd stuff... dead, alive, won't charge, intermittently open, you name it. It seems more and more difficult to find a 6 year battery that lasts more than 3 or 4 years.

I agree with Dan. Getting stuck in the middle of nowhere (or anywhere) is dangerous! Get a new Battery!

Some things:

a] I've run into this with Interstate batteries before. They *do not* like to sit.

2] doesn't matter where you bought your battery. If it's bad, any interstate dealer will exchange.

c] the guy at strauss is an idiot.

4] Batteries sometimes do weird things. A battery showing 0 volts can sit overnight and show 12V. But there's no amperage there.

V] Get a new battery.

If the battery runs down completely in 5 days, it is not operating near capacity. With a termial voltage of 12 Volts open circuit, it sounds like a cell has gone bad. Guy at Strauss auto is not too smart. A good battery should output 13.8 V to 14.4 V. I am not sure 1/2 hour would be enough to recharge a fully discharged battery.

Interstate batteries have a good reputation, but any battery can fail prmaturely. I am almost positive any interstate dealer will honor the warranty on your battery. Is Strauss auto an interstate dealer? Maybe he didn't want to give you credit for the prorated life of your battery. Interstate may have a website to direct you to dealers in your area. Even if you don't have the original receipt, there is usually some marking on the battery for the date of manufacture. Some batterys even have a way to mark when they are istalled.

Bottom line. If it were me, I would replace the battery before heading out across country. If the battery fails and strands you on the interstate, that can be no fun and dangerous.

Good luck on your trip. Enjoy your visit to San Francisco, it is a most beautiful city. I think there are plenty of brickboard members in the area also.

Dan.