Battery not charging, having trouble diagnosing

Hi KZ folks,

I'm having some trouble with a newly purchased '77 KZ400. It's in decent shape with low miles, and the electrics don't look like a birds nest, but it's not charging. It will start and run (with some issues that I'll be chasing down later), but the battery reads 12.5 volts with the engine running, and does not charge. I've gone through the electrical connectors - including the ones in the headlight - and hit them with deoxit, but still no luck. The shop manual gives some interesting instructions on how to test the alternator output.

Alternator Output Test, 1974-1977 and 1977 to 1978 Deluxe A models
1. Remove the left hand side cover and the headlight unit
2. Disconnect the 6-pole connector from the left hand side, and the 9 pole connector in the headlight housing
3. Disconnect the white wire from the rectifier at the battery positive lead
4. Connect the positive terminal of the 0-20 DC volt meter to the white wire which was removed. Connect the negative volt meter to a good ground.
5. Remove the right hand side cover (Caution: In the next step, do not allow green and brown leads to touch anything. Also, do not allow them to remain connected for longer than is necessary for this test).
6. Disconnect the green and brown leads from the voltage regulator. Temporarily connect these leads together.
7. Start the engine and run it at idling speed (1,110 - 1,300 rpm). Do not run it at a faster speed.
8. Observe volt meter. If it indicates 14 volts or greater, the alternator is okay. If output is less than specified, either the alternator or rectifier is defective.
9. Stop the engine. Refer to figure 2. Connect a 1-ohm 200-watt variable resistor, such as a commercial carbon pile, between the white wire and ground. Do not disconnect the volt meter.
10. Start the engine, then gradually increase its speed to 5,000 rpm. Adjust resistor at the same time engine speed is increasing, so that output voltage is maintained at 14.5 volts
11. Stop the engine. Do not change the setting determined in step 10.
12. Refer to figure 3. Connect the positive terminal of an 0-20 ammeter to the white wire, which goes to the rectifier, and the negative terminal to the carbon pile.
13. Start the engine, then run it at 5,000rpm. If the ammeter does not indicate 13 amperes or more, the alternator or rectifier is defective.

I feel like an idiot, but I can't find any 6-pole connector on the left side. There's a white wire that splits out of the positive battery terminal, but that's all I can see.

Does anyone know specifically which connector this is referring to?

Good news! Don't even start by testing the generator (BTW, it isn't an alternator) output. Start by testing the rectifier. That test is very easy to perform and is described in the Kawasaki Service Manual; you only need an ohm meter to test it. If that fails the test replace it; otherwise move on to test the regulator. That test is also in the manual.

It is more likely that either the rectifier or regulator is faulty rather than the generator. If you need a rectifier or regulator let us know and I'll give a link to a great place to get quality units at low prices.

Ed

650ed wrote: Good news! Don't even start by testing the generator (BTW, it isn't an alternator) output. ...

I thought alternating-current-generator is the definition of "alternator".

loudhvx wrote:

650ed wrote: Good news! Don't even start by testing the generator (BTW, it isn't an alternator) output. ...

I thought alternating-current-generator is the definition of "alternator".

No disagreement here, but anyone trying to find out information about a KZ "alternator" will be out of luck because all Kawasaki documentation (service manuals and parts diagrams) I have ever seen refer to it as a generator. I guess it's Japanese / English translation quirk. Ed

Some FSMs refer to the "Dynamo" located under the "Alternator cover."

Good Fortune!

Patton wrote: Some FSMs refer to the "Dynamo" located under the "Alternator cover."

Good Fortune!

Good point! The KZ400 FSM does call it a "dynamo." The link below shows the testing instructions for the '74 - '77 charging system (starting on page 154) including the rectifier and regulator. The Kawasaki.com parts diagrams refer to it as a generator. Ed

home.online.no/~ivbekkel/Workshop%20manu...al%20P%20137-175.pdf

The Clymer manual calls it an alternator. I've always called it a stator. Whatever floats your boat, I guess, with apologies to technical correctness

I'll check the R/R and report back. Thanks!

As I understand the lingo --
The dynamo aka alternator is composed of the "stator" (electrical windings) and the "rotor" which turns/rotates inside the stator.

Some manuals refer to "left side engine cover" instead of "alternator cover," and "dynamo" instead of alternator," all while using "generator" in the index. :lol:

Good Fortune!

When I went to turn the bike on tonight, I found the battery to be completely dead, even though the ignition was off.

Snooping further into the wiring, I found one of the bullet connectors was very toasty and had melted the insulation onto an adjacent wire. Now we're getting somewhere!

I tightened up the female end of the connector, sprayed some deoxit (it was *very* corroded) and reconnected it.

While the KZ's battery was recharging, I connected my strom's, and attempted to turn the bike over. It sounded like the battery was dead already, cranking over very slowly. The connections were all fine. I kept cranking it, added full choke, and after maybe 20 seconds of on and off cranking, it all but stopped turning, and then sprung to life in an uncanny way - I've never seen anything like it, it was something out of a horror movie.

The readings at the battery terminals on the multimeter were all over the place. The rectifier heatsink quickly (within a minute of engine start) became hotter than hell to the point where it could not be touched, and I shut the bike off. I think I found the culprit.

Is there anything else I ought to check before replacing the rectifier?

Would verify integrity of ground connection where negative battery cable attaches to rear of engine.

And also assure the battery cable clamps are clean and snugly attached to the terminal posts.

Good Fortune!

tonezone wrote: When I went to turn the bike on tonight, I found the battery to be completely dead, even though the ignition was off.

Snooping further into the wiring, I found one of the bullet connectors was very toasty and had melted the insulation onto an adjacent wire. Now we're getting somewhere!

I tightened up the female end of the connector, sprayed some deoxit (it was *very* corroded) and reconnected it.

While the KZ's battery was recharging, I connected my strom's, and attempted to turn the bike over. It sounded like the battery was dead already, cranking over very slowly. The connections were all fine. I kept cranking it, added full choke, and after maybe 20 seconds of on and off cranking, it all but stopped turning, and then sprung to life in an uncanny way - I've never seen anything like it, it was something out of a horror movie.

The readings at the battery terminals on the multimeter were all over the place. The rectifier heatsink quickly (within a minute of engine start) became hotter than hell to the point where it could not be touched, and I shut the bike off. I think I found the culprit.

Is there anything else I ought to check before replacing the rectifier?

I have a bit of a problem understanding your testing techniques. :blink:
In a previous posting I stated:

"Good news! Don't even start by testing the generator (BTW, it isn't an alternator) output. Start by testing the rectifier. That test is very easy to perform and is described in the Kawasaki Service Manual; you only need an ohm meter to test it. If that fails the test replace it; otherwise move on to test the regulator. That test is also in the manual.

It is more likely that either the rectifier or regulator is faulty rather than the generator. If you need a rectifier or regulator let us know and I'll give a link to a great place to get quality units at low prices."

In my follow-up posting I even gave a link to instructions on how to test the rectifier, regulator, etc.
home.online.no/~ivbekkel/Workshop%20manu...al%20P%20137-175.pdf

I don't know if your bike's problem is the rectifier, regulator, or something else, but was there some reason you subjected your bike's electrical system to the risk of melting wires instead of starting by simply testing the rectifier? Frankly, it kinda makes me feel like trying to help is a waste of time. Ed

Hi Ed,

Apologies. I thought that it may have simply been a corroded connection that I didn't notice before, and because the Clymer manual (which I was working out of) prescribes testing the regulator / rectifier by measuring the voltage with the bike running, that's what I did. I hadn't considered that it might be a risk to do, and yes, I should have tested the rectifier first.

I'll go through the proper rectifier test tonight based on the factory manual.

Thanks