Topic: Not Charging CB550K [Problem Solved!] [Problem Broken Again!]

[scottly]

OK, here is my diagnosis. You found your rectifier to be suspect, and I think you were correct. Pat yourself on the back for your first diagnosis, and you didn't even know how to use a meter a month ago!! However, you mistakenly substituted an incorrect part, and that's where the fun started. But hey, look how much we have all learned! Try a direct replace rectifier, and let us know how it goes.
Scott

[campbmic]

I doubled up on one of the AC terminals? Could this be the problem? What store would carry a 3 phase?
Thanks a ton for your help! I would ride to Arizona and buy you beer but I would have to have about 30 backup batteries right now.

I'll try and get a 3 phase tomorrow and put it in and see if it works. This thread should definately be helpful to anyone in the future with charging issues.

[scottly]

Dammit, I just totally edited away my last post!!

[Laminar]

I doubled up on one of the AC terminals? Could this be the problem? What store would carry a 3 phase?
Thanks a ton for your help! I would ride to Arizona and buy you beer but I would have to have about 30 backup batteries right now.

I'll try and get a 3 phase tomorrow and put it in and see if it works. This thread should definately be helpful to anyone in the future with charging issues.

As I mentioned before, I have a known working stock CB550 rectifier I can send via Priority Mail and you'll have it in 2 days. Let me know if you're interested.

[scottly]

Glad you caught that before I blew it away, Laminar.

[TwoTired]

I'm pretty sure the radio shack rectifier is a two phase rectifier.  You need one more phase to make a complete circuit or 1/2 of another radio shack part in addition to what you have.

Yellow wires attach to the AC or ~ marked post  Green to to the - and Red to the + of both components.  One of the RS device will have no connection to one AC post.

You can test the old rectifier for function using the analog ohm meter.  Takes 12 tests.
Measure ohms of green to each yellow and write down reading
Then reverse the meter lead polarity and measure the green to yellow again,  write that down.
Repeat the above with the yellow to Red terminals

A good rectifier will have ∞ (infinity or no meter deflection) with one meter probe polarity.  And some low resistance on the scale (meter needle deflection) with the opposite meter probe polarity connection.

[scottly]

I'm pretty sure the radio shack rectifier is a two phase rectifier.  You need one more phase to make a complete circuit or 1/2 of another radio shack part in addition to what you have.

Go back and read the previous posts; we have already determined the Radio Shack rectifier is SINGLE phase. For that matter, I have never seen a two phase rectifier, or a two phase system, for that matter. Perhaps you could educate me on this oddity?

[TwoTired]

The pointer posted before clearly refers to a full wave bridge rectifier which is a two phase rectifier.
"25A, 50V Full-Wave Bridge Rectifiers
Model: 276-1185 | Catalog #: 276-1185 "

As such it has four diodes in it.  See first pic.
Then redrawn in the second pic.

The third pic shows what is needed.  Two more diodes that can be used in a second full wave bridge rectifier.

[scottly]

Bull#$%*. A full wave, single phase bridge rectifier has 4 diodes. Period. A full wave, three phase bridge rectifier has six diodes. Period.

[TwoTired]

Fine.
Just add the connections of the second bridge to utilize two more diodes of the second bridge.  Presto, a six diode three phase rectifier assembly.

[scottly]

I'm still waiting for your tutorial on 2 phase systems...

[TwoTired]

I'm still waiting for your tutorial on 2 phase systems...

Actually, the rectifier doesn't know or care about whether AC inputs are single phase or two phase.  If you connect a single four diode bridge rectifier to the Honda alternator it rectifies two distinct phases of AC sine wave input 120 degrees apart, since that is how power is created in the alternator windings.  All you need are two more diodes for the third phase, which can be found in a second bridge rectifier.

The bridge specified by R.S. is NOT labeled single phase because its operation is not phase dependent.  The single phase designation is something you applied to it, without merit.  When used in this application, it rectifies two phases.

If campbmic wants to use the rectifier(s) he already has... See:

http://forums.sohc4.net/index.php?topic=19155.msg200097#msg200097

If you'd rather convince him to spend money on something else, that is between you two (or three).

Clearly, I'm not wanted here.  So, I'll just go.  (Actually, I should have just stayed away while you reinvent the wheel.)

[Spanner 1]

The idea of buying another Radio Shack rectifier is a good one....... 1/2 of the 'new' rectifier would take care of the 3rd. phase of the alternator ( which is currently  shorted to one of the other phases on the 1st. rectifier = no worky at all ).....
And a bonus of a 2 diode unused portion which would always be available as a built-in spare should one ' junction' of the bridge fail.....I love it....!!

[campbmic]

Well I purchased another four diode rectifier from radio shack. I won't be able to test out the double rectifier setup until around 10PM tonight ( I have 3 hours of European History after WWII on Thursday nights  ) but I will let you all know how it goes. Laminar, I'm going to see how this goes tonight and if it doesn't work I''l just buy your rectifier.

Also, if my alternator is producing 12V, 10V, and 8V out of the three yellow wires does the rectifier transform all 30V into DC volts or does it not work like that? What I'm asking, "Is my alternator producing enough electricity?"

Thanks!

[Spanner 1]

The thing about our sohc alternators is this........ it's part of a system comprising of the alt., rectifier, regulator and the battery. It's impossible to isolate one part ( like the alt.) and make sense of any voltage reading....Honda does not even go near that.....!
The only reliable test is the simple voltage vs. rpm. at the battery... up to 14.5v at 5,000 rpm. Not happening ?...next is un-plug the alt. and do the windings test ( already explained )...In your case, the proper rectifier set-up will fix the problem IMO.....
3 hours of post WW2 European History....yuck, get a beer , quick  !!!!

[campbmic]

Alright I put the new rectifier in and it is charging! Yay for rectifiers! However, now there is a kind of whining/winding noise coming from the alternator. It sounds very strange and I'm not for sure if its normal or not. I will try and post a video but does this noise typically occur?

[scottly]

Yahoo! You are charging!!! Not sure what to make of noise from the alternator; these alternators have no mechanical things to them. I'm guessing you are so gun-shy, you are attributing normal engine noises to the alt...
Congrats on fixing your charging problem!! 

[campbmic]

Well I took my bike on about a 10 mile highway trip with the headlight not plugged in

When I left my battery was 11.8
When I returned it was 10.8 and rising and eventually got up to 11.5 about 10 minutes later

I'm afraid that if I tried to take an hour long trip at night then the battery would die. What could cause this?

[scottly]

Wow, what a disappointment!! You mean it got up to 11.5V 10 minutes after you shut it off?

[campbmic]

Yea I got home immediately killed it and measured it at 10.8 and it was steadily rising. After about 10 minutes I checked it again and it was steady at 11.5.

[scottly]

Ok, and last night, you thought it was charging? What were your readings then?

[scottly]

I'm guessing you don't have the rect wired properly, but the noise thing is making wonder. Does your electric starter work, when the battery is charged? My 750 had the starter mess up once, the starter motor spun, but didn't turn the engine. Turned out to be a loose rotor, spinning on the end of the crank. I don't know if the starter drives the rotor on your bike. Just a thought....

[campbmic]

Last night I tested the battery at around 11.9 while the bike was on. I started the bike and set the idle to 4k and it was just barely charging. If I set the idle to 4k now it still just barely charges, anything below that seems to not charge.

[scottly]

Yeah, you're not charging.

[campbmic]

I just blew up my MM trying to test my spark plugs too so I had to go buy a new one