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testing alternator--battery dead

aapasquale

aapasquale
Hi All;
My Odyssy battery which has been working very well (until today), seems to have given up the ghost after a short life of 8 months--the only inkling of this was alternate flashing of ABS lights the day before--just ran the bike a few minutes, shut it off and powered up again and all was good--the alternator light did not come on at all except at start-up which is usual--put her to sleep at night and morning was pretty flat--almost nothing--certainly not enough to turn it over--There seemed to be more than adequate juice until, well, there wasn't!!--I have put a good 12,000+ miles on this battery--
it's a 1994 R1100RS--The battery will not take a charge at all now!--any thoughts?

Is there a test I could run to see if alternator is functioning properly?

Thanks,
Tony
 
The battery will not take a charge at all now!--any thoughts?

Is there a test I could run to see if alternator is functioning properly?

Thanks,
Tony

The battery won't take a charge from what source?
Bike
Tender
Regular battery charger

A quick test of the bike charging system is simply to measure voltage at the battery with the bike running, just over 14V is good.
You'll need a charged battery to start the bike of course and you need to make sure it won't become disconnected when the bike is running.
I just had to add that last in case you try this with a battery temporarily rigged up with jumper cables.
 
I love my Odyssey battery.
Frankly it is more likely the alternator failed.

ditto motoradmike
I think it should kick up 14V even at idle. Certainly it should at anything over 3000 rpm. Put a fan in front of the bike though.
If that reveals a lower voltage than expected, separate the two components of the system and test separately.

Charge the battery with an external source to be sure it didn't just die.
Even an AGM battery will not tolerate complete discharge to zero for very long.
If memory serves it should charge up to something like 13.8V when healthy.
I don't think it is possible to vibrate or shock the mil-spec battery hard enough to hurt it and not damage the rest of the bike.
(just sayin')

It is an automotive-style alternator.
If you are willing to pull the alternator you can take it to Autozone where they have a machine that will spin it and produce numbers and a pass/fail assessment. I have not done this for an oilhead, and getting the part off of a car is much easier.

I bought and use a little Battery Tender on mine. The Motronic and the clock are really "on" all the time, and draw a small amount of power even with the machine sitting idle.
 
I love my Odyssey battery.
Frankly it is more likely the alternator failed.

ditto motoradmike
I think it should kick up 14V even at idle. Certainly it should at anything over 3000 rpm. Put a fan in front of the bike though.
If that reveals a lower voltage than expected, separate the two components of the system and test separately.

Charge the battery with an external source to be sure it didn't just die.
Even an AGM battery will not tolerate complete discharge to zero for very long.
If memory serves it should charge up to something like 13.8V when healthy.
I don't think it is possible to vibrate or shock the mil-spec battery hard enough to hurt it and not damage the rest of the bike.
(just sayin')

It is an automotive-style alternator.
If you are willing to pull the alternator you can take it to Autozone where they have a machine that will spin it and produce numbers and a pass/fail assessment. I have not done this for an oilhead, and getting the part off of a car is much easier.

I bought and use a little Battery Tender on mine. The Motronic and the clock are really "on" all the time, and draw a small amount of power even with the machine sitting idle.

There are a number of issues that can cause a problem of this nature. However, batteries fail far more often then charging system components. You MUST know with CERTAINTY if the battery is good or bad. Everything else is a waste of time if the battery is bad.

People will commonly state that something is too new to have failed. But anything that comes with a warranty/guarantee is telling you up front the company is not perfect and they are willing to do something for products that fail too soon. Start your diagnostic trail by knowing with certainty the condition of the battery. If it's good you look elsewhere. If it's bad hold the presses until you have a known working battery.
 
You MUST know with CERTAINTY if the battery is good or bad. Everything else is a waste of time if the battery is bad.

I do agree with this. I was just bragging on the Odyssey battery.
The battery is certainly easier to get to; in effect BMW agrees with the statement as well.
Whenever it takes an R&R to even diagnose, I always start with cheapest/easiest.

Speaking of which: This may turn out to be a loose connection.
The Odyssey (PC680?) has to have these L-shaped brass adapters for the cables to reach,
so there are more surfaces to be dirty and more nuts to be loose.
 
I do agree with this. I was just bragging on the Odyssey battery.
The battery is certainly easier to get to; in effect BMW agrees with the statement as well.
Whenever it takes an R&R to even diagnose, I always start with cheapest/easiest.

Speaking of which: This may turn out to be a loose connection.
The Odyssey (PC680?) has to have these L-shaped brass adapters for the cables to reach,
so there are more surfaces to be dirty and more nuts to be loose.

Of note, Exide Technologies, the supplier of many of BMW's batteries filed for bankruptcy a few days ago.

http://www.bloomberg.com/news/2013-06-10/exide-technologies-files-for-bankruptcy-in-delaware.html
 
My point would be that as mentioned, without a good battery, reasonably charged, alternator tests tend to be meaningless and often misleading. With a discharged or faulty battery in the system and connected, voltage readings are almost always lower than they would be with a sound battery. It is thus easy to conclude that there is a problem with the alternator when in fact it is a marginal battery, or even just an OK battery that is low on charge.

This can be an expensive conclusion if your source for the alternator won't take it back when you discover that the new alternator didn't cure the problem. Other than initial crude checks I wouldn't even attempt to troubleshoot a charging system unless I was positive that there was a sound battery in the system.
 
Thought I might chime in and add this little tidbit to the discussion...................A while back I mentioned in the Oilhead section that I wanted to swap out the incandescent lamps in the dash of my 1100RT with LED's since many of them were burnt out anyway. I was informed by another member that there is a 4watt lamp in the dash which is actually a part of the charging circuit. If this bulb was burnt out or swapped with a lower voltage consuming LED the charging system would not function. Just a thought....but when you turn the ignition key to the on/start position, you should see a red light showing a battery symbol.......if not.....maybe this is the culprit?
 
Of note, Exide Technologies, the supplier of many of BMW's batteries filed for bankruptcy a few days ago.

http://www.bloomberg.com/news/2013-06-10/exide-technologies-files-for-bankruptcy-in-delaware.html

Chapter 11, restructuring. It may mean something short or long term, or maybe not. No need to panic yet. Their biggest current problem is the high price of recycled lead which makes up 40% of their cost of goods sold. Then the republic of california shut down their primary lead recycling source.
 
Thought I might chime in and add this little tidbit to the discussion...................A while back I mentioned in the Oilhead section that I wanted to swap out the incandescent lamps in the dash of my 1100RT with LED's since many of them were burnt out anyway. I was informed by another member that there is a 4watt lamp in the dash which is actually a part of the charging circuit. If this bulb was burnt out or swapped with a lower voltage consuming LED the charging system would not function. Just a thought....but when you turn the ignition key to the on/start position, you should see a red light showing a battery symbol.......if not.....maybe this is the culprit?

Thanks for the thought--the red light with battery symbol DOES come on with ignition switched on
Tony
 
My point would be that as mentioned, without a good battery, reasonably charged, alternator tests tend to be meaningless and often misleading. With a discharged or faulty battery in the system and connected, voltage readings are almost always lower than they would be with a sound battery. It is thus easy to conclude that there is a problem with the alternator when in fact it is a marginal battery, or even just an OK battery that is low on charge.

This can be an expensive conclusion if your source for the alternator won't take it back when you discover that the new alternator didn't cure the problem. Other than initial crude checks I wouldn't even attempt to troubleshoot a charging system unless I was positive that there was a sound battery in the system.

I've ordered a replacement battery. We'll see how this story progresses. By the way, I should have added from the start that a week before this happened I drove to Americade (300 miles) and drove back back in a 6 hour deluge. The bike seemed to be not affected at all for an entire week after this except for what I mentioned previously.
Tony
 
I've ordered a replacement battery. We'll see how this story progresses. By the way, I should have added from the start that a week before this happened I drove to Americade (300 miles) and drove back back in a 6 hour deluge. The bike seemed to be not affected at all for an entire week after this except for what I mentioned previously.
Tony

Reading the first 2 sentences seems to imply you have not verified the battery is bad?
 
I rebuilt the alternator in my 94RS at 125,000, because the nose bearing was making noise. I had another low miles alternator given to me by a local BMW shop to use for parts. I compared the brush wear in my hi-miles alternator to the brushes in the low0miles alternator and was surprised to see the hi-miles alternator still had over 1/2 the brush life in them. My bet is that unless the alternator develops a failed rectifier/regulator, the brushes should be good for at least 200,000 miles.
 
I've had the battery on a charger for four days solid and it hasn't even begun to take a charge-I think I can
safely assume battery is dead!

Tony,

It'd seem so...but it isn't necessarily true: some chargers won't charge a connected battery if the charger doesn't see some juice in that battery. That is, it will recharge a partially-charged or low battery, but won't charge one that's completely discharged. What kind of charger are you using?
 
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Tony,

It'd seem so...but it isn't necessarily true: some chargers won't charge a connected battery if the charger doesn't see some juice in that battery. That is, it will recharge a partially-charged or low battery, but won't charge one that's completely discharged. What kind of charger are you using?

I will pull the old battery out today. It's a BMW charger ehat I use regularly when the bike is put in shed each night.
 
It's a BMW charger ehat I use regularly when the bike is put in shed each night.

Over the years, BMW has distributed chargers that are both "dumb" (they'll provide current without regard to the state of the battery) and "smart" (they'll charge only if the battery has some minimal level of residual charge).
 
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Pulling out the battery is the only way to check the connections. Not sure if that has been done yet? That would be the first thing to check since the oilhead alternators are pretty bullet proof.

Next thing to try is charging the battery outside of the bike. If it takes a charge have it load tested to properly determine the state of charge. If the charger will not do anything I sometimes jumper the suspect battery to a known good one and let the good one discharge into the suspect one to bring the voltage up to where the charger will work.

Then decide if a new battery is needed and only after checking with Odyssey about warranty. They are a pretty good company.
 
Pulling out the battery is the only way to check the connections. Not sure if that has been done yet? That would be the first thing to check since the oilhead alternators are pretty bullet proof.

Next thing to try is charging the battery outside of the bike. If it takes a charge have it load tested to properly determine the state of charge. If the charger will not do anything I sometimes jumper the suspect battery to a known good one and let the good one discharge into the suspect one to bring the voltage up to where the charger will work.

Then decide if a new battery is needed and only after checking with Odyssey about warranty. They are a pretty good company.
Hi Happy Wanderer,
Took plastic off today and lifted tank so I could get to the battery to jump start it in order to check alternator. Alternator is working fine putting out about 14 volts. Turned bike off after idling at 2,000 rpm for about 5 minutes. Checked battery voltage.....almost nothing. Glad to establish that alternator is not the problem. I will remove the battery from bike tomorrow and will try your idea of jumping to a known good battery and see if its heart starts beating again. By the way, I called the company i got the battery from and there is a two year warranty on the battery. It will be pro-rated for the 8 months this one has been used.
Tony
 
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