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 !