Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Reading the voltage directly from the coils and not through the rectifier, Set the meter to AC and take a reading.  If the reading is strange switch the meter to DC and take the reading.  If you are getting a reading in the 12.5 to 15 Volt range your charging coils are putting out DC and not AC and you don't need the rectifier.  You may see higher voltages than that with no battery hooked up,  Even at 15vdc and only 10 total amps available you will not hurt the battery if the voltage is a little high.

If you are getting DC voltage in that range you can hook up your coil directly up to the solenoid post and ground.  Make sure to connect the positive side of the output to the correct post on the solenoid, the ground can go to any ground point on the engine/frame.


Remember take these readings without the rectifier hooked up.

Good luck.

carlb wrote:
Well here is what I got.
 As I posted before there are actually four wires (two pairs) that come out from behind the shroud. Each pair are joined together to give you one wire with a connector on the end.  See photo in Reply #18.  (I never have really understood the two wires to one wire, unless there are four coils.  Maybe I should call Honda and see if they could give me an explanation).

Black probe to grnd. Red probe inserted into the wire connector
Engine @ idle reading from left wire - meter set to VAC    3.6V to 3.9V
Engine @ idle reading from right wire - meter set to VAC    1.6V to 1.7V

Engine @ full throttle reading from left wire - 12.5V steady
Engine @ full throttle reading from right wire - 5.3V steady

With meter set to VDC  Left wire 0.01V  Right wire 0.01V

If I had to take an uneducated guess I would say that I may have a coil that's not right.  5.3V compared to 12.5V. But what do I know.
Maybe in all my switching wires around in the beginning trying to figure out the rectifier hook ups I burned up one of the coils.  I know there is a chance that I at one time
I had the ground terminal on the rectifier swapped with one of the + output terminals on the rectifier. I had the first terminal and third terminal hooked up backwards.
I think.  If I did would, or could that have burned out or damaged one or more of the coils?  If so, I guess that could explain the wide difference in readings between
the two coil wires

Well from your readings it is putting out AC and not DC.  What reading do you get when you set the meter to AC and probe both wires at the same time.  If it is actually AC output you dont want to ground either of those wires.  You would only ground the negative wire after it was rectified to DC.

At this point I would take the shroud off and see exactly where the wires are coming from and how many coils you have. 

carlb wrote:
Okay I pulled the flywheel.  I have two coils, each coil has two wires coming.  All four wires are the same color.
One wire from coil "A" is joined to one wire from coil "B"
The second wire from coil "A" is joined to the second wire from coil "B"
The two wires that have connectors on the end that I have been connecting to the rectifier. Have a wire from coil "A" and coil "B"
It is supposed to be a 10A coil system.
Flywheel has 4 magnets.
This mean anything to anyone?
While I have things apart.  Is there a way for me to check the coils with an ohmmeter to see if they are okay? If so any thoughts as what kind of readings I should get
if they are okay. And what I should see on the meter if they are bad, or partially bad or shorted.

This morning I hooked an ohmmeter between the two coil wires. That is the two wires that have connectors on the end.  Not the two that come off of each coil. "I got a tone".
I probably should have gone between a wire and ground as well.   Maybe that reading would mean something to those that know about these things

From your description of the splicing, the coils are in parallel.  A single phase rectifier fed by two coils to my mind implies the coils are in phase.  I'm not sure if each coil should have the same voltage output.  In parallel the voltage across them must be equal but independently, this is not true.  I'm thinking there is nothing wrong with your coils; there are two to produce more current than a single coil.  I'm a little rusty on this stuff.

Are you removing the splice?  How are you checking the coil voltages independently?

Since AC, wire color does not matter, your rect/reg will flip the negative half of the alternating current into positive.  Your voltage at the solenoid and battery will vary with RPM and battery voltage.  That is, even with a regulator, the output of the regulator will be higher when the battery is not at full capacity, than when it is at full capacity.  If your battery is significantly drained, I wouldn't necessarily be concerned about the high voltage on the output of your regulator (battery post).  I assume you are keeping a load on the output, as JimmyM says.

Paul

manjestic wrote:

Hi Paul
I don't know or understand much about these type of things.  I had been checking the output by taking a reading from each wire with the meter set to VAC.  Red probe to to wire
black probe to ground.  But I was assuming that each one of the two wires were connected to a single coil (that is the two wires that were being connected to the rectifier.  Which now seems not to be the case.  As you said, the coils appear to be hooked in parallel.  So I'll have to think about what that means as far as readings go.
Thanks for your input. I know very little so any information is a help.  I tend to be able to understand what things do, but have no clue how some things work.

Do not check each wire to ground.  Place a probe into each of the connectors and read the AC voltage from both wires.  You only need the ground AFTER the rectifier as it is DC at that point. 

After checking the two wires in the AC mode of your tester

1 Connect both wires to the rectifier and switch your meter to DC
2 connect the output wires of the rectifier, negative to ground and positive to either the battery or the battery post on the solenoid.
3 take a voltage reading (DC) on your battery with the engine off should be 12.5 or 12.6.
6 start the engine and check the battery voltage at idle
7 bring the RPM's up to full throttle and check the volts again. 

If the battery was in the 12.5 to 12.6 range to start with I would expect to see a voltage around 13.5 or so.  If the battery was low to begin with it may take a while to bring it back up to normal voltage.

If you have a battery charger charge the battery first and make sure it is up to 12.5, 12.6 or so.

jrtrebor wrote:
Am I correct in thinking that you were were alternately measuring each of the two wires across chassis ground.  I'd be interested in what the AC voltage across both wires (no chassis ground) is at idle and full throttle, and with and without the rectifier/regulator (and load) connected.  I hope I'm not covering ground already er...covered.

What I'm after is how the two wires (representing the two coils in parallel) are connected to the rectifier.

manjestic wrote:
Thanks carlb  - This is sometimes part of my problem I don't even know how to correctly hook up and check things.  And yes I was "measuring each of the two wires across ground".  I'll have to put things back together and take a measurement across both of the wires coming from the coils.  The readings given in the photo below were taken with
the battery hooked in the system.  I hadn't checked it that day but when I checked it yesterday it was reading 12.4V.  I'll put it back in the charger and make sure it
has a full charge.
The diagrams that I have found for this rectifier. And the wiring diagram for the tractor that it came off of.  Show or call terminal #1 the Batt + terminal. The wire runs from the
rectifier to the key switch B+ terminal.  Along it's way there it is tapped into and that wire goes thru a main fuse and connects to the Battery + terminal.
Terminal # 2 is called or referred to as the Ign. terminal.  The wire goes from the rectifier to the key switch Ign. terminal.  Along its way there it is tapped into and that wire goes to a small 3 fuse, fuse block.  I hope some of this is making sense
I really appreciate all you guys help with this.  I can do a lot of things. But I can get lost when it comes to this kind of stuff.  As you can imagine with
me taking readings from the coils wires with one probe to ground.  I've simply been trying my best not to burn something up. By doing something stupid.
That I didn't know was stupid to do.  You won't be insulting me by stating simple, (doesn't everyone know this) kind of things.

I must say i have not seen a rectifier with two hot output terminals on it, but it may be more common on tractors than snow blowers.  The light might be fine with the 17.5 volts while that would be too high for maintaining the battery. 

Maybe use term 1 @ 17 volts for the light and term 2 @ 12.5 for batt charging. 

Term one may be limited by a voltage regulator built into the rectifier