Battery Voltages - what is good vs. bad?

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SkooterG

Purveyor of Crooked Facts
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Help!

Today my FJR was acting up. It's been a long-standing problem that has gotten progressively worse, but for this thread I am want to concentrate on the battery.

Here's the deal: 2004 FJR1300. 162,000 miles. New battery put in at 149k, 5 months ago. I have had an intermittent starting issue since May or so, both with the previous battery and the now current one. It got better for a while with the new battery, but it's been getting worse for a while again. Today I go to start my FJR for the first time today and I get only a few slow cranks from the starter. Sounds like the battery is dead. It's cold for around here, about 45 degrees. I rode the bike yesterday with no issues. Due to the 'issue' I have been periodically checking battery voltage and it's about 13.25V after sitting for several hours. A-Ok.

So after this happens today, I get the multi-meter out and the battery reads 12.85V. Over the next 15 minutes or so it rises back up to 13.05V.

I turn the ignition 'on'. After fuel pump cycles, I measure voltage now at 12.80V with ignition and the tail and side marker lights on. After 30 seconds or so, it's reading 12.57V and still slowly going down.

Turn everything off. After 10 minutes I get 13.04V. After over an hour I get 13.09V.

So now I meaure while cranking. The engine started pretty quickly, but I got a reading of 11.10V and 10.8V or so.

Immediately after starting, I am reading 13.90V which quickly raises to 14.0V

After idling a few minutes, 14.14V. Reving engine give 14.17V

So I do a bit of riding. I get a no-start episode which I will detail in another thread. After repeated cranking, battery is pretty low. Clock resets and I have to push start the FJR as battery won't turn it over anymore. I ride about 10 miles home and when I get there, I measure 13.91-13.94V while idling. After I shut it off, battery reads 13.70V and is going down quick.

After an hour and a half, battery is at 13.20V.

So! Everything above looks fairly normal to my un-trained eye - at least concerning battery voltage. I suspect my 'issue' may be a worn out starter or something else, but I am trying to eliminate the battery as a problem. Even though it's only 5 months old, I know of other 'new' batteries that have failed rather quckly.

So what do you experts think? How valuable is a load test? It seems the reading I got above, particularly after the initial slow cranking look pretty good. What saytheth you all?

Any help is greatly appreciated.

Oh BTW, while doing all this today I measured the g/f's BMW F65GS voltage. Bike is 3 and half months old, and was last ridden a week ago. 12.88V.

And I am using a small portable RatShack multimeter. Good enough, right?

 
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Unless you've got some corrosion in the cables, I don't think you can eliminate the battery.

I know I need a battery, I'm just too cheap to go for it at the moment. I have cold cranking issues, but I'm fortunate in that it's not often cold enough to matter. When it gets below 40, if it doesn't fire right up on the first couple of turns, it's going to have to be pushed or jumped.

My bike's been sitting about a half hour, ambient is low 50s, voltmeter shows 13.1 volts with key on. After about a minute of key on but not running, it had dropped to 12.6. Hit the flashers, drops about .3 when the lights flash. Went under 10 while cranking, but fired right up, shows 13.9, 14.0 volts. After a few seconds of 4000 RPM, goes to 14.1 or 14.2, which is what I usually see while riding.

Datel voltmeter is connected via relay to the battery terminals, relay is triggered by the running lights. Simplest way to have it come on with the key and not need a switch in line with the voltmeter.

When I have a cold start problem and drain the battery, it'll show 13.5 while I ride, and slowly climb as the battery recharges.

I replaced the battery late '06 with the cheapest battery I could find, so I deserve a failure soon enough.

 
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Today my FJR was acting up. It's been a long-standing problem that has gotten progressively worse, but for this thread I am want to concentrate on the battery.I have had an intermittent starting issue since May or so, both with the previous battery and the now current one. So now I meaure while cranking. The engine started pretty quickly, but I got a reading of 11.10V and 10.8V or so.

I get a no-start episode which I will detail in another thread. After repeated cranking, battery is pretty low. Clock resets

I suspect my 'issue' may be a worn out starter or something else, And I am using a small portable RatShack multimeter. Good enough, right?
Cheap DVM = good enough -- especially when comparing voltages to other known good batteries.

I suspect your 'issue' is "something else".

A worn-out starter would've registered lower voltages when cranking (and a poor battery would've done the same).

I think all your voltages are fine.

I also think that there's an issue (extant in the FJR community) with FJR intermittent starting problems and 'clock resetting' that hasn't been successfully resolved (I think there's been another thread or two on that?).

On the plus side: good diagnostic data provided, so-far... :)

 
I also think that there's an issue (extant in the FJR community) with FJR intermittent starting problems and 'clock resetting' that hasn't been successfully resolved (I think there's been another thread or two on that?).
I agree. But for the first 5 years and 140k, never a problem starting.*** HOT, cold, short trips, other electrical loads on. My FJR ALWAYS started easily. So whatever issue I have is more of a recent variety. Though could be the same as other FJRs suffer while much earlier in their life.

***Other than those 3 times it didn't start due to a dirty ignition switch.

Greg, you need IonBeam... :rolleyes:
He has been pinged. ;)

 
Help!
Today my FJR was acting up. It's been a long-standing problem that has gotten progressively worse, but for this thread I am want to concentrate on the battery.

Today I go to start my FJR for the first time today and I get only a few slow cranks from the starter. Sounds like the battery is dead. It's cold for around here, about 45 degrees. I rode the bike yesterday with no issues. Due to the 'issue' I have been periodically checking battery voltage and it's about 13.25V after sitting for several hours. A-Ok.

Your battery seems like it's OK. The problem sounds like a poor connection in the starter circuit. Why not do a simple voltage drop test from the positive battery cable to the starter and the negative battery cable to the starter case. This will eliminate unwanted high resistance in both cables and all the connections. You won't even have to disconnect anything to do the test.

 
Since the "poor connection" guess has been taken

I'll go with a"decaying field in the starter armature". :unsure:

Or worn out brushes.

 
Here is a place to start. In this thread I outline a way to check the starting circuit. I've got a cheapo DMM ($7) from Harbor Freight that I consider disposable for diagnosing problems like this. I clip the leads to the involved terminals, Velcro the DMM to the handlebars and just leave it in place until I have gotten results over time. If these tests don't clearly show the problem I will see if I can locate my high amperage current shunt and this will let you measure actual cranking amps.

The problem may well be the starter. As the starter brushes wear the commutator the brushes drag commutator metal (usually copper) into the insulator spaces between the commutator segments. This causes the segments to leak current which reduces starter torque and increases current draw. Many repair shops have a lathe specifically to cut commutators and break these shorts. Older shops use a growler to test for coil shorts.

I'm not going to be online much today as I will be at home still battling household problems left over from the 12/11 ice storm. I've got two work crews scheduled and will have to shut off power to the hovel until they are done.

¡Buena suerte!

 
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Older shops use a growler to test for coil shorts.
¡Buena suerte!

WOW! I haven't heard that term in a long, lonnnnng time.

My Dad had both the lathe and growler in his home shop.

You electrical guys are like some mystical cult. :unsure:

 
Slow crank, decent voltage while cranking, fairly new battery, correct running voltage, correct resting voltage, high bike mileage all says it's starter time. A bench test of the starter would confirm.

 
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SkooterG: Just a very quick question from your friends Art M. and I. Is this one of the batteries that lived on the back upper shelf of your bedroom closest for two years before you finally remembered you had it? You Freaking Pinche Dingbat!

Now, on a positive note: Do you want to pull the starter out of my "Miss Lucy Liu" and give it a try in "The Dirty Old Whore" before you spend big bucks on a new starter for yourself? I am riding the new BMW for the next three weekends so Lucy is available to give her starter up for a month. Oh by the way, since it's you I'm dealing with, you have to reinstall my starter!

 
As stated by others, your battery sounds like it has plenty of juice and is being properly recharged during running. The fact that the voltage at the battery voltage drops to ~11 V during cranking is not unexpected.

That leaves the following possibilities:

Starter motor

wire between starter and solenoid

solenoid

wire between solenoid and battery

wire between negative terminal of battery and ground.

Before I spent money (or time) on replacing the starter, I'd do some more voltage checks:

To rule out the last item, measure the battery voltage with the negative test lead on the frame (maybe you already did?). If the voltage still only dips to ~11 V during cranking the ground wire is fine. Next, measure voltage at the starter motor terminal during cranking. It should be approximately the same as the voltage at the battery. If so, the problem is in the starter.

If there is a large drop in voltage there, move back to the solenoid and make measurements on either side of it. The solenoid has a set of contacts inside that can get crusty and introduce resistance. Corrosion on any of the wiring terminals can do the same thing.

 
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Hopefully the battery and starter cable tests that people are suggesting are covered in the procedure that I linked to in my earlier post.

 
Wow, great help folks. I may need more as I try to figure out what you are telling me. I am not sure when I am going to get to this. Hopefully within the next few weeks. Getting to the starter is a PITA as airbox has to be removed. While you all were writing above, I was writing 'the rest of the story' which I posted in below. I see many of you are way ahead of me and have answered a lot of my questions already.

Thanks again! Now I am a lot more confident I can get this licked!

SkooterG: Just a very quick question from your friends Art M. and I. Is this one of the batteries that lived on the back upper shelf of your bedroom closest for two years before you finally remembered you had it? You Freaking Pinche Dingbat!
No, Senor El Pendejo Grande, it is NOT that new/old battery. That never used WestCo battery was dead when I went to install it in July, so a new one was purchased. And thanks for the offer of your starter, but its somewhat of a PITA to get to. And more importantly, I have a spare already that I bought from a salvage yard.

The Rest Of The Story:

I have an intermittent starting issue. I need help in trying to figure out what is wrong.

Problem started back around May ‘08. Slower cranking, battery draining quicker. Very subtle differences. At that time FJR was almost 5 years old, with about 140k on the clock and the original battery.

Problems progressively got worse, but slowly. Very intermittent. Every once in a while, starter/engine cranking speed would drop off to nothing quickly. After a pause, and maybe a key/ignition recycle, 2nd or 3rd starting attempts would be successful. Usually with wide open throttle. Engine would catch and start at times, even with very slow cranking rpm. As I said, problems progressively got worse in that it happened more often. Sometimes clock/trip meter would reset while cranking - obviously a low voltage condition from battery being depleted from more than normal cranking.

One thing I want to reiterate - starter cranking speed even when ‘good’ is not what it was when new, and drops off quickly if the engine doesn’t start right way, which it usually does.

So now it’s July ’08, a few days before NAFO and the problem though intermittent just recently gets bad enough that I decide to replace the 5 year old 150k original battery, thinking it‘s got to be the battery . I get a replacement from a local Batteries Plus store. BTW, I have them load test my old OEM battery and they say it tests good.

So new battery goes in, but I still have the same problems, though they are now not as frequent. During NAFO I tried to demonstrate for many folks, but slow cranking/no fire problem only happened every once in a while. On the few times it did occur for my audience, unanimously the opinion was, ‘bad battery’. But this was a brand new battery. And still, VERY intermittent in nature.

Though the issue is better with the new battery in July, things continue to very slowly get worse. Oh yeah, I forgot to mention, problem only occurs when engine has been run and is hot or warm. It never happens on cold start up. At this point I am guessing a worn starter. I mean, I got 150k+ on this one.

Then, on October 31st it happened for the first time. No start. Starter would crank at a slow speed then quickly drop off. I mean from slow crank to no crank in about 1 second. After several attempts battery was dead. Battery went dead a lot quicker than it should have. After several attempts, I was able to push start it.

3 weeks later, it happened again. Same as above. Slow cranking, quick battery drainage, resulting in a push start. BTW, I should add that my FJR is pretty much ridden daily. So in between these no-start episodes are a lot of normal starting (albeit with slow cranking) and other ‘episodes’ where it starts on 2nd or 3rd attempt.

Now, in December we finally start getting some colder temperatures here in Arizona (40s), and I start getting my hard starting ‘episodes’ for the first time while trying to start the FJR for the first time of the day when it’s cold. Remember, this problem has always been with a warm or hot engine problem. These episodes ocurred a few times, but I still always got a start. Then, for the last 3-4 weeks even though starter cranking speed seems slow, engine has been firing up almost instantly. Almost zero episodes. Like the colder weather is helping somehow. I was thinking I didn’t have to worry about this for a while. I told a forum member that on the phone two nights ago! “All is good right now”

Until yesterday. Cold FJR (about 45 degrees) and right off the bat, starter cranks slow and tapers off within a second to nothing. And no start. So I get out my multi-meter and start measuring battery voltages as I detail in THIS thread. A short while later, it starts right up. I run an errand (short ride) and it starts right up. I go to the grocery store, and when I come out, I get slow cranking (but ‘normal‘ for past several months) and no start. Even after several attempts. Battery quickly goes dead. After about 5 attempts I finally get a successful push start.

Now, I don’t want to have to spend a lot of money to diagnose this thing. I am afraid to take it to a dealer due to a) incompetence, and B) intermittent nature of the problem. I don’t want to pay a lot of $$$ for diagnostics that don’t show anything. Nor do I want to just start replacing parts myself to find out what’s wrong, though I may have to. That’s why I am here, to get all you guys who know better than I, to tell me where I should be looking.

To me it acts like the battery is bad. But it’s only 5 months old and shows good resting voltage of 13.20V or so. Though I realize it’s happened before where a ‘new’ battery goes bad relatively quickly. I’ve been meaning to get it load tested. How helpful will that be?

For the longest time, I really believed it was a worn out starter. That’s why it acted up when warm, why it always has a reduced starter speed, and why it would drain the battery so quickly. I imagine a high current draw/poor performance situation due to a worn starter. I was so sure of myself I even purchased a salvage starter to replace my original. But it’s a PITA to change and I don’t want to do it unless I am reasonably sure that is the root cause. I know, get off my lazy *** and get-r-done.

What other possible causes could it be?

Positive cable connection from battery to starter? Corrosion?

There is no negative cable running off the starter, I guess it’s grounded to the engine, but what about the ground cable from the battery to the frame? Could that be it? Where the fuke is it located?

On the last no-start, after cranking the engine *coughed* ever so briefly right off the bat, then nothing for the remainder of the cranking until the battery was dead. I believe it’s done the same on the other no-start situations, though not sure. This makes be wonder if there is something else going on causing the problem other than the starter or the battery.

How about a worn out stator? Or regulator/rectifier? Either one having an intermittent fault that sometimes leaves the battery not fully charged?

So, what thinketh you all? What am I not understanding or missing? How do you think I should proceed first? What do I check? How? Somebody come and hold my hand, tell me it’s going to be ok for crying out loud!

I love my dirty ol whore of an FJR with 162k on the odo. But I can’t stand an un-reliable vehicle. I have been lucky that on all 3 no-starts, I have been in a place where push-starting was possible. But the very intermittent nature of the problem has prevented me from attacking it more aggressively. It’s been getting worse and more frequent, but still not that bad. But after yesterday’s no-start episode, I have had it.

HELP!

 
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Battery grounds directly to engine at lower front right. A sick starter will go pretty much exactly as described, pulling more and more juice until it's almost dead shorting the battery, and pulling so much juice there's nothing left for other systems. And they will be moody, until they get tired of your cheatin heart and head to Miami for good-one of the nice things about starters, plenty of warning. Unlike those ***** alternators, everything's fine and then BOOM, they're warming someone elses ***, and you're left wondering how such a charged relationship could have gone flat so fast. Oh yeah, I been there pally, and it ain't pretty, not at all........ :drag:

 
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Ok, so I tried some different readings, can anybody tell me what they mean?

I measured voltages while cranking. Engine always started after about a second, though cranking was slow. This was on a cold engine. I wish engine wouldn't have started so quickly so I could have gotten a longer Voltmeter reading.

+ battery terminal and ground to frame, 3 different trys. Readings between 6 and 7 volts.

+ battery terminal and ground to - terminal, 3 different trys. Readings between 7 and 8 volts.

+ terminal of starter and grounded to frame, 2 trys. Reading of .6 -.7 volts.

So these cranking readings are lower than the 10v I got yesterday. Is the approximate 1v difference between ground to frame and battery enough to show a problem with my ground cable? Or is that normal?

And what about the paltry .6v reading at the starter? Is that right?

Oh, btw. I hope to install my salvage starter sometime in the future. But this bike is my everyday transportation and according to the SM it's a big job. Airbox and throttlebodies need to be removed. Hopefully I can get to it in the next few weeks. Unless I HAVE to get to is sooner.

 
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