Overcharged but won't turn starter?????

Damn bike!
'82 Maxim 750 J
I tinkered with the suspension this morning, then it started fine - from cold, hadn't been started for a few days except a 1 minute run to hear if exhaust was blowing, then jumped on and did around 8/9 miles, stopped to tweek shox - with engine running and twin spots on, did another 2.5 miles to home, stalled it at the back door tried to re-start and the battery was dead!
The starter solenoid was rattling away with not enough power to turn the engine, Put a tester across the battery terminals and it read 18 to 19 volts and climbing.
Tried to start it 30 mins later and the engine turned over but not enough power to start.
Any thoughts anyone?

 

You might have two problems to Investigate.

1. Overcharging. The Voltage should not ever exceed +14.8
The system is supposes to Max at 14.2 -to- 14.5

2. Starter.

The Starter may need Maintenance. The Commutator end may be Fouled with Carbon Dust from the Brushes.
You may Need New Brushes.
You may have to overhaul the Starter.

Do an archive search: Chinese Puzzle

 

Hey did you ever get a new battery? or are you still messing with that old one you had mentioned in your previous post.

If your battery is junk your wasting your time even talking about it.
The charging system is not designed to work with a battery that has shorted cells or will not hold a charge. You may actually damage the system if you continue to run with a bad battery.

So My advice is to:

Start with fresh battery.
Check your alternator brushes (10mm wear limit)
Check and clean the surfaces the brushes ride on.
Check the connector to the voltage regulator and make sure its not melted.
Report Voltage readings Idle, and 2000 rpms

On these bikes the charging system is so critical for proper ignition operation. Remember the plugs will foul and your spark will be weak and the bike will not start properly.

If you want to post pictures. go to photo bucket and resize to fit the format here.

Hope that helps
MN

 

Battery is 4 weeks old, waiting for rain to stop (hopefully this week!) to check outputs/connections etc.

 

Ok if the battery is 4 weeks old you need to have it tested. Trickle charge it and take it to a shop that can "Load" test it to make sure its within specs.
In our new world of global economy alot of the stuff we buy comes from China and I have learned not to trust anything even if its new.

So lets start from square one here and lets see if the battery makes the load test first.

Once we know the battery is good then you need to check those altermnator brushes out and see where they are at.

If they check out and every thing inside there is clean. Then remove your tank and check the wires that come up to the voltage regulator and see if the three wire connector is in good shape or is it melted.

When you get to that point then you'll need a good digital multimeter to make some accurate measurements. If you don't have one maybe you could borrow one from someone.

You are reporting that you are seeing 18-19 volts. I would double check that with a digital multi meter. That alone will ruin a new battery in short order. You may have a regulator problem if it is charging too much.
Let us know what you find.

MN

 

your starter solenoid might have wet the bed
cross the two big terminals with a screwdriver, see what happens
key OFF, in neutral

 

OK fellas, and girls...
Update:
I left a battery conditioner connected overnight, 45 mins after disconecting it the batterry voltage was showing 22v.
I stripped the starter, all shiny and clean in there with 6-7mm of brushes showing, cleaned connections anyway and stuffed it back in.
I then stripped the alternator, all shiny and clean also with about 18-20mm of brushes showing, then started to strip starter solenoid and accidently snapped the two fine wires going into the coil :roll: non-repairable!
Found another which is suitable = working OK.
Checked voltage at the three pin connector from the alternator and showing an average 6.20v at each white wire.
Went for a short run and whilst going down the hill in second saw that the temporary voltmeter which I fitted was reading 15v plus at the battery terminals! (it only reads upto 15v), the same at 25 mph upwards!
Dead reg/rec I think?
continued on five minute trip turned off and showing 13v,after an hours rest then another 5 min trip I turn off and she started OK and the batt was showing 13v.

 

you left a battery tender on overnight and checked batt voltage after 45 minutes showing 22v.


the battery is junk. no if's and's or butt's. probably boiled all the acid out and cooked the cells to the point they are shorting out.

batteries are supposed to take a charge that will absorb through all the cells top to bottom. yours is taking the charge but it's not being absorbed. it's all sitting at the top THUS accumulating to 22v.

change the battery, THEN see how the rest of your electrical works. IF YOUR STILL HAVING PROBLEMS. in order to do accurate testing you have to have working parts. a battery reading 22v does no good for checking anything else out.

 

The 22v was after a 10 mile run, it then dropped to normal - I'm going for the reg/rectifier... the battery is now stabilised at 13.2v, good or bad there shouldn' be a charge of 15+ volts.
I've already got a new battery waiting to go on, but I ain't frying that too!
I'm trying to find which other reg/recs from other models will do the job.

 

I have never heard of a 12 volt battery producing more than 13 volts.
As far as I now the only way to have more than 13 volts is to have an active charger attached.
Are you sure your volt meter is accurate?

 

The Voltage Regulator is one of the most common components across the years and models.

You'll probably find a used one with no trouble.

Before you hook-up the New Regulator ... INSPECT the Quik-Connect Plug into the Harness from the Regulator.

Look for the Big Red Wire to be Seated in the Connector where it belongs.
Often, when the Reg goes bad ... the RED Wire loosens from Overheating and Pulls-out of the Connector where it is supposed to be captured.

 

Found the number, searched it on ebay... XJ900, 600, 650/turbo, 700, Xs400, FZ600, FJ600... there's loads!!!

 

The battery is toast, get a new one asap. Do NOT try to save it or charge it further. I have never heard of a battery generating more than 4 volts greater than it's rated voltage.
While the bottom line is correct, I must take issue with some of your statement Snowwy,

I would agree with that.

Not sure how you got that reasoning since the charge occurs chemically (called conversion) across the face of the surface area of the grids that is exposed to the acid bath. Sulfidation will limit the active surface area and this tends to occur toward the bottom of the cell and work it's way up commensurately with the severity of the sulfidation (thanks gravity). The only absorption that takes place is when the acid is first introduced to the cell.

True but the correct word is stored. And the battery is storing too much

This is the quote that I cannot agree with. When the plates sulfide, they loose effective surface area ergo they cannot give off more voltage. It will only provide less voltage potential. This indicates that there is a serious defect in the battery.

I doubt seriously that charging this battery is going to accomplish anything other than wasting electrons and making an opportunity to blow up a battery. I would strongly recommend against this action.

On this I will agree, 12 volt parts don't like to be over-voltaged. It lets out the magic smoke and the parts don't work right anymore.

 

Thanks for that, new battery in shed and I'm waiting to aquire a replacement reg/rec before I go further,

 

+1 mdee, maybe a second meter is on order
shorted cells can't make higher voltage, not possible, shorted cells = less cells = less volts
sulfated cells make the same voltage, just less capacity (a/hr's)
changing and charging, two different words but close
i seriously doubt a 12 volt battery can read 22 volts, check the meter

 

That was two different test meters one digital, one analogue... we live and learn :wink:
I have another digital one I could try tomorrow too, but today the battery is still stabilised at 13.3v.

 

Be interesting to know what the voltage is with the bike running at 3Krpm.

I'd think if the charging system was really running up to 22V every bulb (and maybe the TCI) would have checked out in short order.

 

Rick wrote:

Members need to have accurate information when they ask a question.
Responding to a Post with speculation or inaccurate information may cause a situation that the Questioner is in ---> BEFORE ---> You Posted what you thought he should do ... to be made WORSE.

If you KNOW what a Member needs to do; by all means offer your knowledge and experience.

Don't guess.
We don't need two people guessing.

If you are going to Post something that is going to need to be un-explained.
(( I think I just coined a new word,))

Preface the Post with with some remark that will let the Member know your guessing, ,too.

"I'm not a Wrencher; but I play one on this Forum"
"In My Opinion and no other living persons"
"Once Upon A Time"

 

isn't what you said basically the same thing i just said? only i said it in plainer engish. and my reasoning comes from delco sales reps i beleive it was.

 

TCI is Transistor Controlled Ignition, where CDI is Capacitor Discharge Ignition. While they both perform the same basic function (triggering coils) they do operate differently.

TCI was an improvement over the CDI and is what the 80s XJs have.

By 1990 Yamaha was going to computerized ignitions. This is what the SECA II seems to have as it has a single pick up coil.

Generically Yamaha seems to refer to them all as igniters.

I'm completely at a loss how a charging system running at 15V (in spec) can result in a battery that reads 22V when shut off. The battery should be discharging into the electrical system in that circumstance.

 

Um...yes, you did say the battery was dead but my post was to point out an obvious error in your information. If you don't know what you are talking about, please, PLEASE don't fire off with mistaken information without prefacing it first with "in my humble opinion" or "I'm not 100% certain about this...". It's ok to quote sources when possible, it adds to the validity of the statement. We aim to educate folks here and we do that by explaining things as clearly as we can with valid knowledge.
If my explanation was too in depth, just say so and I'll gladly rephrase it to better meet the needs of our inquiring audience. Let's get back on track with the issue at hand please.

 

‘22’ on the digital meter may really be 2.2 (two point two)
No starter turny at 2.2 volts.

I have an electronics background. I have maintained my own automotive batteries for years. I did a quick Internet search to see I’m missing something.
I feel very confident you will not get more than 13 volts from a static 12 volt battery.
13 volts is being generous accepting some degree of error in meter or reading.

MN-Maxims questioned if you are attempting to revive old, broken or somehow bad battery. I am beginning to think that is the issue. If the battery was deep discharged (2.2 volts is deep) and especially if let sit for days in deep discharge, then the battery will be permanently damaged.

I have not seen posted that you have attempted a known good battery, either on the bike or to test meter(s) readings.

Post-post:
Possibly .22 (point two two) volts. If the digital meter is auto-ranging, it is easy to mis-read.

 

Mdee, good points all^^^. I agree with the static voltage, I've never seen more than 13.8 on any 12 volt battery, even new.

 

The reading was in excess of 15v as thats all the meter reads upto'
I thought the igniter was a different part again - a sort of spark booster in the ignition system - I have one of those too.
This 22.1v did eventually drop to around 13.5v,
and would it discharge any other way if the reg/rec was duff?

 

I have had this digital meter for in excess of 10 years, I know how to read it, I know what a decimal point is, It doesn't auto select range - it has a dial
The meter was initially set to read upto 20 vdc, it started at around 12-13v then slowly (roughly at 0.1 per second and getting slower over approx 2 mins) climbed to read '1' so I had to turn it up a step to 200 vdc range and it then stopped climbing at 22.1v, I merely read what it displayed - I don't know WHY it read 22.1 volts, and why would I lie?
The battery was connected to the bike at the time and the ignition was turned off, the battery is NOW showing 13.3 volts (I have not removed it from the bike yet as it hasn't stopped raining for long enough).

 

No worries Dub, we are just making observations and comparing notes. I confess, your problem is the first time I've ever heard of a battery outputing that much voltage in a static state. A real brain-teaser...
A thought just crossed the mind, does the meter have fresh batteries in it? I've seen old batteries in meters lead to wonky readings.
The only way I could see the battery doing this is if it had been overcharged (and do I mean overcharged!). I'd put a call into Yuasa and ask them what gives. I'd also be doing an alternator check once the new battery is fitted. If you don't have any odd readings out of the charging system, you have a mystery on your hands.

 

What about the readings I got of roughly 6.2v at each white wire from the alternator? at revs between 1000 -2000, (I got no tacho)

 

I don't think the Alternator on any XJ-Bike is going to make anything close to 22 Volts.

If I had to place a bet on how 22 Volts came into this discussion, ... I'd bet on:

Meter on wrong scale.
Misread meter.
Operator inexperience troubleshooting electrical.

 

TOPIC NOW CLOSED.

 

[quote="Jay~Dub]What about the readings I got of roughly 6.2v at each white wire from the alternator? at revs between 1000 -2000, (I got no tacho)[/quote]
Was that AC voltage or DC? I don't have my book handy so troubleshooting is a bit of a pain at the moment.

 

Was that AC voltage or DC? I don't have my book handy so troubleshooting is a bit of a pain at the moment.[/quote]

Read at DCV setting

 

Read at DCV setting[/quote]

White wires have AC output from the stator. You would read between two of them with the meter set to AC. I don't believe Yamaha has a spec for them. Since it's a field coil alternator the output will depend on how the regulator/rectifier energizing the field coil. I've only seen AC output specs for fixed magnet alternators.

If you're pegging a 15V DC gauge at the battery at 2K RPM or more your stator and rotor are fine. You need a meter that will read higher so you know what the charging voltage really is. I don't have the book here but I believe the spec will be below 16V. If you're high it'll be the regulator/rectifier or the wiring to it.

 

digital meters require batteries. usually 9v. i've seen meters do funky things if that 9v battery gets low.

if your meter runs on battery. might try a fresh battery.

the manual doesn't give specs either. just says 14v 19A @ 5000 rpm.

 

Thanks, I will see what the weather is like later and I would like to re-do some tests so as to confirm my previous results, as I am getting a bit p*ssed off with other people making out that either I don't know what I'm doing, or I'm lying or don't know how to look at a test meter... Its getting just a little bit tedious, so I'll take a break until I know more.
Thanks to everyone else for all the positive input though.

 

Update:
FIRSTLY! - thank you to everyone for your input.
Right..., cleaned and inspected all connections,
Starter solenoid: contacts were slightly burned and pitted.
Reg/rec connection block: the terminal with the red wire shows a definate sign of overheating, i.e. the spade connector blackened and the surrounding plastic slightly melted.
Repaired some dubious looking connections.
Bought a new test meter.
fitted new battery.
replaced starter solenoid and reg/rec (from an XJ900).
at low revs, its reading 13 -13.90v and now showing an average 14.30v at 60 mph in 5th, at the battery terminals,
Does this all sound OK now?
I would like to do a proper AC voltage test on the generator, it all seems to be working, but as I just bought a new meter I should make good use of it!

 

Sounds just about right. Glad you are pressing on with the project rather than giving up. Alternator should be outputing about 40 volts peak-to-peak (from the calculation of 14vdc regulator output and this conversion formula (RMS x 1.414) x 2=P-P). You would measure between any two leads of the alternator output.
Good luck and enjoy having a nice new meter, they can be a great tool!

 

but the meter is only going to read about 28.2 vac/rms

 

Please Robert, my head! I'm just a welder!.
- (RMS x 1.414)???
do I test between any 2 white wires from the genny, at the AC setting, or all wires i.e. 6 readings?
I never give up btw, I always win, somehow. :twisted:

 

AC volts 3 readings, call the wires a,b,c you read
a-b=
a-c=
b-c=

 

OK, Thanks. I can do that! but where does RMS (x 1.414) come from

 

OK. You asked!

RMS is the acronym for Root Mean Square Now read on........

To calculate the RMS value of a sine wave, multiply the peak value by 0.707. The peak value is, of course, one half the peak-to-peak value. To go the other way, reverse the order of operations. That is, if you're starting with an RMS value, divide by 0.707 and then multiply by two to get the p-p value. Another way to convert from RMS to p-p is to multiply the RMS value by two square roots of two: RMS x 2 x SQR(2).


Or more simply, to convert from RMS to peak to peak voltage:

(RMS x 1.414) x 2=P-P

For example:

120vac x 1.414= 170vac 170 vac x 2 = 340 vac P-P

 

WaMax, you rock!

 

i think it comes from Mars
doesn't really matter, meters read AC in RMS volts, oscilloscopes read AC Peak to Peak and are usually noted p-p
DC volts are just DC volts, well not really but close enough for us

 

OK, pass the paracetamol...
the last bit looks do-able.
So I can use the figure 1.414 for this test?
The 120vac figure, is that the total of the three readings at the connecter?
I'm not really that stoopid, I did start an electronics course at school but when I found out I was colour blind it kind of put an end to that idea :roll: so I didn't get to learn this stuff.

 

So these guys have been frying my brain just for a laugh??
Actually I was going to mention that about meters, I want to talk to you I think, my head is happier with your language
so I stick the red bit on the bit with the little cross and the black bit on the bit with the line....

 

"So these guys have been frying my brain just for a laugh??" no everything everyone told you is the truth
right now the best thing to do is measure your ac on the 3 wires and write them down for future reference, your getting the right volts out so the right volts must be going in, case closed, move on
i don't think it's a good idea to run it with the alternator unplugged
do something easy like set your floats or shim the valves

 

If only this were so, you have to pay more for a meter that will do this. Not all can.

Yup, quite so. They also read DC.

From an XJ perspective you are right. There is always a small bit of ripple on the rectified DC but it causes no issues other than a bit of hum on the stereo that I installed without a filter. A trip to Radio Shack fixed that.
Jay, make the list that Polock showed you and measure the output of the alternator by poking the meter leads into the connector housing. Not a good idea to run the alternator with it disconnected.

 

"do something easy like set your floats or shim the valves"
If ain't broke don't fix it!
I'm waiting for a YICS tool now, (I can get one for £25 ($40 ish)
as carb sync is the only issue pending.
I will need a new front tyre in a few weeks it needs matching to the rear (Shinko) anyway - it does'nt like white lines!