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krb

Magnum 310-8 charging issue

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Posted (edited)

Turns out I do have a magnum Single.  ( creeping (galloping??) old age and 16 horses i don't always remember what engine is on what)

 

This is the regulator that should be on your 10hp Magnum. 

 

If you find it disconnect the plug...set your multi meter to AC (very important AC) put one probe in each of the outer holes.  Start her up and get up to at least 2/3 throttle.  You should have 30 volts or more AC showing on the meter.  if you do the stator is good.  if not there are some more tests for it.  If you do get 30 volts then the regulator is potentially bad.

IMG_0065.JPG

IMG_0066.JPG

Edited by pfrederi
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Perform the test as mentioned above and note results then unplug the harness/plug and again insert your probes in the outer terminals and repeat the test and if its higher there is definately a problem with the regulator. Remember AC on the meter for this test.   Next test put meter on DC then go from the center terminal with one meter lead the red one and put the blk lead of your meter to a good ground.

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Hmmm, a conundrum.

 

This one has a plate where yours shows a regulator. My brother will post up some pictures soon. Appears factory.

 

He inherited this maybe 20 years or so ago. His father-in-law bought it new and I doubt he ever altered it and we sure haven't yet. The wiring looks untouched, not even a splice or frayed end.

 

It quit charging at the end of the 2015 mowing season. Last year we just suffered through with jump starting or hooking it to a charger overnight. This year we decided to fix that along with a few other maintenance items. Like brother said, the lights haven't worked since he got it, but we don't mow at night so never worried about it. We live about a mile apart and share the mower.

 

Like I said in the first post, I'm comfortable with troubleshooting and wrenching cars, trucks and farm tractors but this little thing has me stumped...

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You never know what was done to tractors over a 30 year period.  lets try to nail down what we are working on.

 

What is the model # and serial number of the tractor?

 

Does it have tail lights or just a reflector?

Trace the two wires on the light switch, one goes to the lights where does the other go? (Either the ignition switch or directly to the engine)

 

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It has reflectors.

 

I'll go get the #s and check the light wires

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No tailights leans to a 3 amp unregulated system...back where we were.  as you follow the light wire there will most likely be a plastic connector holding 2 wires on the way to the engine.  After that connector the 2 wires coming from the engine will probably be in a sleeve...the diode will l  be on the other wire inside that sleeve.

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Tractor ID # is 2110K804     22564

 

The light switch has black wires with a green tracer. Larger one goes to the headlights, other goes to a connector by the motor which turns into a yellow wire that terminates under the starter, along with the black wire with white tracer which connects to the keyswitch terminal "A".

 

Pictures forthcoming.

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Posted (edited)

The wire with the white trace that comes from the A terminal is eh one that will have the diode.  Do the headlight wire and the white trace wire go into a sleeve between the connector and the engine???

 

This an unregulated k series but loos about the same.  The plastic sleeve...about 1 inch in you will feel a bump   that is the diode.

IMG_0069.JPG

 

By model number this is a 1987 and the first time they used Magnums in the 10hp tractor...That may explain why some things do not exactly match the manuals...they frequently used up old parts wiring etc.at the start of a new model run.

Edited by pfrederi

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54 minutes ago, krb said:

Tractor ID # is 2110K804     22564

 

The light switch has black wires with a green tracer. Larger one goes to the headlights, other goes to a connector by the motor which turns into a yellow wire that terminates under the starter, along with the black wire with white tracer which connects to the keyswitch terminal "A".

 

Pictures forthcoming.

 Between that connector and the engine is where you should find the diode. Probably covered by a plastic sleeve like in my photo.

 

Can't see the connector in your pics

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On 4/16/2017 at 10:31 PM, 6bg6ga said:

 

Lets look at how to check a diode for those that haven't done it before or possibly are a tad rusty on it. The diode has a Anode+ and a Cathode end and the cathode has the line on it. So to check the diode simply put your meter on the diode function and take the negative meter probe and attach to the cathode end and the red lead from your meter to the Anode end of the diode you will get a reading of around .500 or so. Now reverse the leads put the red lead from your meter to the cathode/band end of the diode and your black lead to the anode end of the diode and it reading will be open. This result as mentioned above means the diode is ok. If the diode checks open for both tests the diode is open AKA no good. If the diode checks shorted in either and or both tests it is shorted and must be replaced.

 

Eureka! Finally found the little bugger. It was tucked into the short lead from the motor to the connector and hidden under the starter.

 

With the multimeter I get a reading of 1 and 671.

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6 minutes ago, krb said:

 

Eureka! Finally found the little bugger. It was tucked into the short lead from the motor to the connector and hidden under the starter.

 

With the multimeter I get a reading of 1 and 671.

 

 

Well at at least the diode was in the right place.

More testing

test.JPG

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Test 1 = 12.4v

Test 2 = - 0.2

Test 3 = 1 in both directions

Test 4 = 5.5

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Test 3 Checking charging lead to ground and reversed you say 1 in both directions...Is that 1 ohm or 1 meaning open  circuit (infinite resistance)? 

 

 

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Post #38 would seem to show an open with the leads reversed in my opinion and a acceptable reading with the leads neg to neg, pos to pos. I would say the diode is good. Start the engine and on the DC scale neg probe to ground postitive probe to the cathode band end of the diode and note the reading. You should have a 12.6 on up dc reading.

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pfrederi - it was set to "ohms". 20K I think. It was  "1" like in the first picture of #38. I don't know my way around a multi-meter real well...

 

6bg6ga - I'll check that next. How can I tell the cathode end?

 

Thanks again guys for your patience and efforts,

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Cathode end has the band on it. The negative end on the diode.  In checking the diode if your meter has a diode check that is all you need. On the diode check with the blk lead on the cathode and red on the anode it will register (depends on the meter) somewhere from .4-.7. When you reverse the leads the red on the band/cathode end and the black on the anode end it won't show anything. What your looking for is the junction to be good and neither shorted or open. Having a reading within the range I mentioned means the diode is good.

 

I'm guessing the craftsman meter shows the "1" when its open and shows "000" when there is a short. Just to be sure short the leads together and I'll bet she goes to zero and unshorted its showing the "1"

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I'm thinking you are right. The "1" was at the far left which I thought was odd and I believe it did register 000 the other way. I'll confirm and check the meter manual one evening when I get a chance - probably not this week...

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No need to bring out the manual. Simply turn it on select the diode function test and observe the read out. If it shows the ''1" without shorting the leads then that's its normal display. Once that is done simply short the two leads together and I believe it will show 000 on the display which means its showing a short. Based on the pictures in post #38 the diode is good.

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I probably mentioned this ....  Take your meter set on the VDC scale and go from the diode cathode/band end and the other lead to ground and you should see 12VDC on the meter. If you don't there are several possibilities...A) the diode is breaking down or if the output is less than 12VDC the flywheel may be missing some magnets and therefore puts out little voltage. If the voltage is good it looks like the end of that harness plugs into the ignition switch. Check for 12VDC in the connector end of the plug on that wire (follow it back). If no voltage check continuity from the diodes cathode /band end to the connector at the end of that wire. If nothing replace the wire or connector or both. If voltage is present the check the ignition switch with the switch disconnected and in the run position. Check the schematic noting the flow thru the switch per the usual A,B,C,D or number markings typical with most if not all diagrams.

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Well I finally had an evening off AND it is raining AND no kid duty so I have some shop time!

 

Post # 41: At the cathode end I have 12.3v.

 

Post # 43: For the diode check I have 626 (manual says scale is 400-1,000) at cathode and 1 when reversed. And 6bg6ba you guess correct on the Craftsman meter.

 

Post # 46: At the connector I get 12.3v, following the wire to the key switch I get 12.3v at the "A" (even though that schematic shows it is "R").

 

Sooo, did I get two dud batteries? It has been starting fine but we have also been putting it on a trickle charge thinking it is not charging. Or is 12.3v just not enough, the trouble shoot guide says 12.5?

 

 Thanks 

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Posted (edited)

Krb,

 

Put your meter on the AC scale. With engine running attach the neg meter probe to engine or chassis ground. Put the other lead on the anode side of the diode.  IF the stator is producing voltage you will see AC voltage on your meter.

Edited by 6bg6ga

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Posted (edited)
57 minutes ago, krb said:

Well I finally had an evening off AND it is raining AND no kid duty so I have some shop time!

 

Post # 41: At the cathode end I have 12.3v.

 

Post # 43: For the diode check I have 626 (manual says scale is 400-1,000) at cathode and 1 when reversed. And 6bg6ba you guess correct on the Craftsman meter.

 

Post # 46: At the connector I get 12.3v, following the wire to the key switch I get 12.3v at the "A" (even though that schematic shows it is "R").

 

Sooo, did I get two dud batteries? It has been starting fine but we have also been putting it on a trickle charge thinking it is not charging. Or is 12.3v just not enough, the trouble shoot guide says 12.5?

 

 Thanks 

Ok, meters can vary. Still would like to see the AC output from the stator. In your manual does it say idle or fast engine speed for the 12.5VDC?

Do you have another meter? Can you borrow one?

Edited by 6bg6ga

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A rectifier is an electrical device that converts alternating current, which periodically reverses direction, to direct current, which flows in only one direction. (Simple 1/2 wave rectifier)
 
This is why I would like to have you check the AC voltage coming off the stator. No AC present means the stator could have an open.

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