Topic: Charging Test in Clymer - Please help me understand

[highrpms]

Questions:
What is an ammeter?  Can I use a multi meter or is that totally different? Arent I measuring the voltage at different rpms?
#2 is completely confusing to me.  I located the red positive battery terminal and followed it to the red/white connecter from the battery terminal to the wiring harness. How and what am I connecting?  Is it telling me to disconnect the red battery from terminal or just the two ends of the red/white wire? So am I jsut taking the end from the harness and skipping the end to the battery and inserting the multimeter? red/white lead to red on meter then black on meter to terminal... then start and measure the voltage and rpms?




Test per the manual:
1. Check the battery voltage is normal.
2. Locate the positive battery terminal and disconnect the red/white rectifier lead, and the red power lead. Connect both of these to the positive terminal of the ammeter.
3. Connect the postitive terminal of the battery to the minus terminal of ammeter with a wire.
4. Start engine.
5. Refer to FIGURE 10 Operate the engine at the various speeds and check to see if the voltage measures up to the standard for night and day riding.

[TwoTired]

Questions:
What is an ammeter? 

A device to measure electrical current flow.

Can I use a multi meter or is that totally different?

Depends on the multimeter.  Can you tow a tractor trailer with any old truck?
Multimeters are as varied as trucks are.  And, they have different capabilities/capacities.

Arent I measuring the voltage at different rpms?

You should.  Voltage is electrical potential.  You can have voltage without current.  But, is isn't very useful without current flow.

#2 is completely confusing to me.  I located the red positive battery terminal and followed it to the red/white connecter from the battery terminal to the wiring harness. How and what am I connecting?  Is it telling me to disconnect the red battery from terminal or just the two ends of the red/white wire?  So am I jsut taking the end from the harness and skipping the end to the battery and inserting the multimeter? red/white lead to red on meter then black on meter to terminal... then start and measure the voltage and rpms?

Yup, you're confused.

Test per the manual:
1. Check the battery voltage is normal.

You begin with a fully charged battery.  It must read at least 12.6 V after a two hour rest off the external charger.

2. Locate the positive battery terminal and disconnect the red/white rectifier lead, and the red power lead. Connect both of these to the positive terminal of the ammeter.
3. Connect the postitive terminal of the battery to the minus terminal of ammeter with a wire.

Do you have a separate ammeter capable of 15 Amp readings?  The starter motor will push more than 50 amps through it if you connect it wrong.  Poof.
You don't really need an ammeter to determine charging system integrity.  It's just a nice-to-have.

4. Start engine.

Use kick start.

5. Refer to FIGURE 10 Operate the engine at the various speeds and check to see if the voltage measures up to the standard for night and day riding.

Just measure the battery voltage at idle, 2000, 3000, 4000, and 5000 RPM.
At idle the voltage will probably trend lower.  At 2000 RPM and above the battery voltage should trend higher, but never go above 14.5 V.

Report back an we can proceed from there.

[highrpms]

Thank you for the detailed response. Lil confused still am I just using multi meter to pos and neg of battery directly and reading levels at rpms? Sorry I'm a little slow on the details. I have measured the battery pos and neg while was running and it never moved from the 12.0 to 12.5 volts. It never budged.  Does that tell anything or am I not measuring anything correctly.

[bollingball]

Thank you for the detailed response. Lil confused still am I just using multi meter to pos and neg of battery directly and reading levels at rpms   Yes
I have measured the battery pos and neg while was running and it never moved from the 12.0 to 12.5 volts.   Did you change RPM'S like TT said

[highrpms]

Correct. I held multi meter to black and red terminals and started and ran it from 1000 to 6000 rpms and the needle barely moved at all. Pretty much stayed still in same range whole time around 12. I have anolog meter.

[Spanner 1]

Your bike is not charging..... but what is your bike , yr./model?

[highrpms]

That would help 1976 CB750K

[Spanner 1]

Can you do a couple of tests?.... Leave the Black lead on the battery Neg. and move the Red lead to the Regulator ( has 3 color-coded terminals , Green, Black White ).  Turn on the ignition and read the voltage at the Black term. and the White term.  Whats the readings ?

[highrpms]

Will do. I will do this tomorrow. Sorry I just closed up garage. Very much appreciated. Will post readings asap. Thanks all again.

[Spanner 1]

Goodnight... don't let the BEDBUGS bite   

[TwoTired]

Thank you for the detailed response. Lil confused still am I just using multi meter to pos and neg of battery directly and reading levels at rpms? Sorry I'm a little slow on the details. I have measured the battery pos and neg while was running and it never moved from the 12.0 to 12.5 volts. It never budged.  Does that tell anything or am I not measuring anything correctly.

You have to begin with a fully charged battery.  12 V is a depleted battery, and it will take a while for the battery to change voltage toward a higher level.  A fully charged battery will go to 14.5V rather quickly.  A depleted battery will take about 10 hours to charge from a SOHC4 alternator.

If your battery is down, you have to watch carefully for trends in voltage change over time.  Or, get a big ammeter and splice it into the charging circuit to get an instantaneous charge reading.

On the assumption your alternator isn't charging the battery.  Measure the voltage between the Black and Green leads on the Vreg terminals.  Then measure the voltage on the White and Green leads of the Vreg without the engine running but the Key switch turned on.  You'll want to do these tests quickly if your battery still weak/undercharged.  Turn off the headlight or remove the headlight fuse to extend the battery life  That saves about 5A of current load.

The results of Spanner's VDrop test is good to know, too.

Do you not have a separate 1-2 A battery charger?

[highrpms]

I have 2amp / 6amp battery charger and the battery charged up last week so I think it should be good still i didnt run it. 

Should I charge some more before the tests? 

I will test the regulator voltage today...  Thanks so much guys!
Eric

[TwoTired]

For the third time, make sure the battery is at full charge state before testing the charging system.

Measure the battery voltage. It must be 12.6-7 V after a 2 hour rest off the charger to be at full charge.

[highrpms]

Im slow but here are the voltage readings

I took the readings when i got home and the voltage was 12.35v:
Neg Batt Term to Black Reg Lead = 10.54v
Neg Batt Term to White Reg Lead = 10.59v
Neg Batt Term to Green Reg Lead = 77.3mv

Black Reg Lead to Green Reg Lead = 10.50v
White Reg Lead to Green Reg Lead = 10.49v

Then I charged and then let rest for 1.5hrs and took the readings again at 12.94v:
Neg Batt Term to Black Reg Lead = 10.90v
Neg Batt Term to White Reg Lead = 10.90v
Neg Batt Term to Green Reg Lead = 79.0mv

Black Reg Lead to Green Reg Lead = 10.87v
White Reg Lead to Green Reg Lead = 10.88v


Then I waited another 1 hr (2.5 total) and took the readings again at 12.80v:
Neg Batt Term to Black Reg Lead = 10.93v
Neg Batt Term to White Reg Lead = 10.94v
Neg Batt Term to Green Reg Lead = 72.0mv

Black Reg Lead to Green Reg Lead = 10.87v
White Reg Lead to Green Reg Lead = 10.86v

[highrpms]

ill take again in the am but does this tell me anything and should i test anything else?
thanks

[TwoTired]

I took the readings when i got home and the voltage was 12.35v:

This is not a fully charged battery.

Neg Batt Term to Black Reg Lead = 10.54v
Neg Batt Term to White Reg Lead = 10.59v

Looks like the vreg is telling the alternator to put out max power, but the input to the Vreg has lost 1.81 Volts between the battery and the  vreg.  This is not good,  Probably have corroded connectors in the wiring, the key switch  contact are nasty, and the fuse clips are corroded.  The voltage loss in that path should be 0.5V or less.

Then I charged and then let rest for 1.5hrs and took the readings again at 12.94v:

Then I waited another 1 hr (2.5 total) and took the readings again at 12.80v:

That's better.  I'm hopeful that the battery is a good unit.

Would have been nice to see the Voltage vs RPM readings that I requested earlier after the battery was fully charged.
Then we could see if the charging system is working or if there is simply too much voltage lost going to the Vreg/alternator.

Cheers,

[highrpms]

I will test the RPM voltage when I get home I didnt want to fire the bike up at 6am - haha...  

This is the readings I took this am after a full night sitting the voltage was at 12.57v:
Neg Batt Term to Black Reg Lead = 10.82v
Neg Batt Term to White Reg Lead = 10.82v
Neg Batt Term to Green Reg Lead = 66.9mv

Black Reg Lead to Green Reg Lead = 10.76v
White Reg Lead to Green Reg Lead = 10.76v

[highrpms]

TT:
Looks like the vreg is telling the alternator to put out max power, but the input to the Vreg has lost 1.81 Volts between the battery and the  vreg.  This is not good,  Probably have corroded connectors in the wiring, the key switch  contact are nasty, and the fuse clips are corroded.  The voltage loss in that path should be 0.5V or less.



So I should follow that path and clean all the connections.  I have seen the fuse clips and the all look good but Ill take them off and clean them any way.  As for the key switch contacts is that internal to the ignition? How is that looked at and cleaned. 

Again sorry for all the very general questions I just rather do as much as I can on my own (obviously w your help). 
Thanks

[TwoTired]

So I should follow that path and clean all the connections. 

I would.

You can actually find the major loss contributors, by placing the voltmeter probe tips on either side of the device or connection in the path.
The meter will read the difference in voltage for that component.  Best to have an accurate wire diagram for this endeavor.

I have seen the fuse clips and the all look good but Ill take them off and clean them any way. 

The fuse clips are made of a material that creates a transparent resistive film when it oxidizes.  Like electricity or oxygen, just because you can't see it doesn't mean it isn't there.  I like to find a dowel or mandrel slightly smaller than the fuse barrel, then wrap crocus cloth around that, and then polish the fuse contact areas with the cloth very bright and shiny.  If there are signs of melted plastic at the clip holder, then remove the back of it and check the solder connection integrity.

As for the key switch contacts is that internal to the ignition? How is that looked at and cleaned. 

They can be taken apart to look at the electrical bits.  The styles vary.  Many have springs that depart upon disassembly.  It's a dexterity/intelligence test. 

I think there was a thread posted about taking them apart.  I don't recall, offhand, which style of switch you have.

Cheers,

[highrpms]

Ok even I know this isn't good. First its hard trying to read voltage while rev ing a bike. I took reading from a 12.6v battery.  Turned key and started and at 1k rpm it was 12v, 3k rpm it was 11.93v, and at 5k rpm it was 9.8v. All readings during were all below 12v...

So this week its scrub all contact points.

What else  tho with the system not charging at all.

[Duke McDukiedook]

Something is wrong with your regulator- make adjustments/checks per the Honda manual- download it in the FAQ section.

[Spanner 1]

O.K....your bike is not charging.... is there close to battery voltage @ the regulator White term ( ignition on ) at the regulator?... i.e.   with the - meter probe on the battery neg., no scrub that, with the meter - on the Green wire at the Reg. and the + probe on the white wire on the Reg. the reading is?... ignition 'on'.

If no reading, turn-on headlight and wait a few seconds for a result.....

[highrpms]

If you see above this was the last time I tested and there is a drop in voltage that is not good (per TT, thanks)...

This is the readings I took this am after a full night sitting the voltage was at 12.57v:
White Reg Lead to Green Reg Lead = 10.76v



Also I took off and scrubbed everything this weekend.  Took fuse block, start seleniod, rectifier, regulator, etc off and scrubed the connections.   Sprayed call with CRC electric cleaner...  Put all back and same results.  no increase in Volts only decreases and all rpm bands. 

I have also took off the regulator and made sure the gaps etc and all were correct etc... 

So I am still searching, the next step was take headlight off and check connections and then try to read voltage and all different points and try to find where the loss in voltage and non charging is happening... 

Ideas, thoughts?
Thanks as always.

[Duke McDukiedook]

Test your stator as per the manual.

[Spanner 1]

If you have 10.76v between the reg. white and green then the field coil is getting voltage and the system should work... Next test would be the field coil. Disconnect the white wire from the reg. and put your meter on low Ohms scale. Test between the white wire and a good ground ( or the reg. green ). The result must be 7.2 ohms or very close to that.... report back !

[highrpms]

great, thank you.  i will test tonight and I will run the stator test this weekend. 

im thinking this has to be something dumb.  i worry about the headlight connections becuase once upon a time there was a front fairing on the bike.

i will test the above but is there anything else i need to look for.  strange thing is all is working correcly.  turn signals, headlights and highbeams, starter, etc...

[highrpms]

spanner - i tested the regulator.  i took off the white lead and i put the meter to it and then the frame ground and got a reading of 0.03ohms.  i then turned the key on and that reading went right to constant 0.00ohms. 

i did the same thing with the white and green leads of the regulator and i got the same exact readings.

what does that mean.  there is voltage across the regulator but what does the ohms tell me?
thanks!

[Spanner 1]

Just to be sure... were just testing the field coil's impedance ( ohms ). So no ignition needs to be 'on' , testing for 'ohms' not volts... seems like you did it correctly, again the White wire that connects to it's terminal on the regulator needs to be pulled-off and one probe from the meter connected to it ( loose white wire ) with the other probe to frame ground/ battery neg. / green terminal on regulator... and the reading was 0.003 ohms? then your field coil is shorted-out, kaput. There is a very slim chance the white and green wires are shorted at/in the alternator cover and there are connectors inside the cover too !!
Also, meter needs to be set at the lowest 'Ohms' scale, but not the 'Diode Test' setting... should say '200 ohms'......

[highrpms]

beacuse im a moron, i measured the regualtor lead not the white wire.  give me 2 seconds....

[highrpms]

not sure dloing this right but i am taking the white lead off the regualtor that hooking a probe to it. then the other to a ground...  i did that and the ohm reading on my manual and digital meters are O.L (over limit) or infinity symbol.  no reading.  i am using the resistance setting on the meter.  digital meter is auto ranging and the manual is up to 1K so... 

i know its user error but not sure what going on here.

[Spanner 1]

Yep, your doing it right!.... the White wire supplies power to the field coil... to measure the field coil to see if its good you did correctly. So, the coil is 'open circuit'... means the wire winding in the coil is 'broke' somewhere in the winding.... still a slim chance the connectors in the alternator have come apart ( under the left cover ), OR the big 2 piece plug that connects to the alternator has burnt/ loose connections, have a close look at that.... has ; white, green, yellow, yellow, yellow on both connectors.... good luck.

[highrpms]

wow you were right the 2 big plugs (from the stator) and wiring harneess are burnt...  and looks like the have had some acid drip on it and man were they stuck together!!!  took 15 minuutes to separate them.. i have a couple pics but i have not ever posted on here before...

so can the stator still be ok with the short or burnt part on there still?
do i have to cut the plugs off and jsut hard wire it all?  what is the solution and tests i need to do from here?

i will try to post the pics now...
thanks

and sorry i was on vacation and i also just got my computer fixed as well.   

[Spanner 1]

I bet your stator/ field coil is good.... I would cut-off each connector and replace with individual insulated 'spade' type male and female connectors ( got 'em at Home Depot ! )... just be certain your crimped connection is good every time ( pull on the wire hard to try to pull it out of the connector to be sure its a good crimp )... start bike , test for rising voltage across battery.... best of luck  

[highrpms]

test

[highrpms]

test

[highrpms]

test

[highrpms]

ok ok ok.  i cut the connectors off and redid them all with with male female connectors.  seems to have worked, kinda. after i made connections i put the charger on it breifly (30 minutes).  after all this i hooked the multimeter and kicked over the bike.  fired right up and i cranked it to about 5000rpms, i didnt have chance to hold it there, but it went to 13.8-13.9 volts...  so thats awesome because now it jumps up instead of going below 12 volts... 

hear is my questions tho...  it didnt jump up to 14+ volts tho.  is that still an issue?  is that 13.8 enough to charge the battery now? did it not jump up to 14+ but is that due to fact it was charged and the regulator didnt need the full 14+ volts???

insights and am i in the clear now?
thanks for ALL the help....

[TwoTired]

You really don't want the battery to change its voltage rapidly whether charging or discharging.
You hope it changes slowly and it usually does unless very very high current rates in or out present.

It take a some time to get to peak charge, and you may never see it with some measurement devices, as it samples what it is testing in intervals. If the Vreg is switching back and forth between full charge and half charge, due to loads on the system, you will only measure some average voltage based on the sample rates of the meter.

If you want to see 14.5 v peaks you may either have to use an oscilloscope, or remove all loads for the system and hold the RPM at 5000 RPM and wait for the battery to reach full surcharge.

13.8 V is a good average to maintain a fully charged battery under use.  When charging a depleted battery, the input current usually continues until 14.5 V is reached, then the charger current is decreased.

To be nice to the battery, the charge voltage should creep up slowly to that 14.5V, as this allows all the electrolyte to get full charged not just the electrolyte near the plates.

Cheers,

[Spanner 1]

As TT says, voltage won't go to 14.5 V across battery until the battery is much closer to fully charged... so with a battery that is still calling for charge a reading of 13.8V is good ( very good  )....... I declare it fixed  !! ... good luck and maybe a 'stimulus' to go-over all the connectors on your bike...