Magnum 310-8 charging issue

[krb 4]

Actually this is an owner issue...

 

Been searching the threads and found that the 310 has either a 3 or 15 amp system. This one is the smaller one with no alternator or regulator. But apparently has diodes?

 

I have the original owners manual and the charging circuit shows only the motor to the switch to the solenoid to the battery. Shows nothing inside or attached to the Kohler Magnum. Doesn't even mention diodes.

 

I'm comfortable with gas and diesel car, truck or tractor engines but no clue on this one. It starts and runs fine (when the battery is topped off) but won't charge. I have no clue where to start or what components to look for. There has to be something on the flywheel that creates a charge right? What job does the solenoid perform other than starting?

 

Thanks,

[pfrederi 17,959]

The diode is in the wire from the stator.  There are two wires one to the lights one to charge.  They travel in a plastic sleeve from the engine to a connector.  The diode is back inside that sleeve (see pic)

 

 

You should have 14.5 or more volts when running.

 

Solenoid has nothing to do with this issue.

 

 

Edited April 16, 2017 by pfrederi

[krb 4]

Thanks for confirming the solenoid wasn't part of the circuit. That had me confused. And many thanks for the wiring diagram, that one is way more detailed than the one in the manual!

 

The amp meter works and the fuses are all good. I'll check the black wire from the stator to the switch and the connections for continuity. Do diodes go bad?

[pfrederi 17,959]

Yes diodes can go bad

I am not an electrical expert but if the diode is working you should continuity only in one direction. If it is open both directions it is bad.

 

I think you will have to open the sleeve and then test for continuity across the diode.  You may have to poke a hole in the wire insulation on the engine side.  Then reverse your multi meter leads should work one way not the other

Edited April 16, 2017 by pfrederi

[krb 4]

I'm no electrical expert either, not even close...

 

Hence this question- If it is a 3 amp system, does that mean a 6 amp diode won't work? My brother (he inherited the tractor from his father-in-law) found this: https://www.milfordpower.com/25-755-31-S-Genuine-Kohler-Diode-Kit-p/2575531-s.htm

 

From what I understand of diodes, they are basically an electrical control valve letting current flow only one way. So is it the diode that limits the circuit to 3 amps or is 3 amps all that the stator creates and thus a 6 amp would work? My understanding of electricity is basic.

 

[pfrederi 17,959]

The diode only controls the direction of flow  voltage and amperage are determined by the stator.   I would guess the 6 amp diode means more amperage than that would damage it.  You should look up your engine on the Kohler site and determine the correct Kohler part number for your diode.

 

What spec# is your engine?

 

Edited April 16, 2017 by pfrederi

[6bg6ga 272]

11 hours ago, krb said:

I'm no electrical expert either, not even close...

 

Hence this question- If it is a 3 amp system, does that mean a 6 amp diode won't work? My brother (he inherited the tractor from his father-in-law) found this: https://www.milfordpower.com/25-755-31-S-Genuine-Kohler-Diode-Kit-p/2575531-s.htm

 

From what I understand of diodes, they are basically an electrical control valve letting current flow only one way. So is it the diode that limits the circuit to 3 amps or is 3 amps all that the stator creates and thus a 6 amp would work? My understanding of electricity is basic.

 

Ok, lets see if I can help. If you have a 3 A diode that means the diode is rated for 3A and yes a 6A diode will work. It will still be limited to the same current output from the stator. Putting on a 6A diode is not going to give you six amps now. You will still have what is being sent from the stator. It just means the diode will be able to take a higher current until it either shorts or goes open.

 

I can supply you with a standard NTE PN for both a 3A diode and a 6A diode and these are rated at 200 volts so they are good enough. PN for the 3A is NTE 5802 and for the 6A is NTE 5854 or the ECG number would also be either 5802 or 5854.

 

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.

 

If your meter doesn't have a diode function test simply put the meter on the resistance scale and repeat as posted above. One way you will show resistance(high) and reversing the leads will show a open and the diode is good.

[6bg6ga 272]

04.jpg shows blk lead to cathode of diode and red lead to anode.

05.jpg shows red lead to cathode of diode and blk to anode

06.jpg shows the resistance scale on the meter blk meter lead to cathode red to anode and a high reading

07.jpg shows the red lead to cathode blk to anode and an open

 

Looks like the picture order is scrambled but if you note the meter lead polarity and the position of the function control on the meter its easily figured out.

 

So, even if you meter doesn't have a diode check you can check a diode on the resistance scale.

 

Personal note here..... Since I don't like to spend mega bucks repairing something using the"Factory" parts I'm cheap enough to change out the diodes myself with the aid of a soldering iron and a couple of pieces of heat shrink tubing. It can be done simply and look professional and it will work and restore your Horse back to normal.

Edited April 17, 2017 by 6bg6ga

[6bg6ga 272]

12 hours ago, krb said:

I'm no electrical expert either, not even close...

 

Hence this question- If it is a 3 amp system, does that mean a 6 amp diode won't work? My brother (he inherited the tractor from his father-in-law) found this: https://www.milfordpower.com/25-755-31-S-Genuine-Kohler-Diode-Kit-p/2575531-s.htm

 

From what I understand of diodes, they are basically an electrical control valve letting current flow only one way. So is it the diode that limits the circuit to 3 amps or is 3 amps all that the stator creates and thus a 6 amp would work? My understanding of electricity is basic.

 

Looking at the specs  Kohler Kit the 6A 1000V PIV diode can be replaced with a 1N5408 diode at probably less that $2 for a pack of two. Note the 1000V PIV rating is NOT necessary in this instance. a Diode rated 200V PIV would be more than high enough voltage for this application. The rating on the diode of 3A means simply the diode is good for 3A and will either short or go open when the current rating is exceeded. Installing a 6A diode in place of a 3A will not cause the current ability to go over what the stator is capable of producing. In other words putting a 6A diode in the circuit will not give you six amps. If it were me I would use a 6A diode in place of a 6A diode and a 3A diode in place of a 3A diode.

Edited April 17, 2017 by 6bg6ga

[6bg6ga 272]

Examples of three different sized heat shrink tubing. After looking at those blue crimp snap together so called connectors I believe someone has been a recipient of the shaken baby syndrome. The blue so called connectors should be banned for anything other than trailer wiring whereas most trailer wiring has been done by a 11 year old.  I suggest either purchase the over priced

diode wiring harness or simply take the plastic cover apart to expose the bad diode cut the diode apart and select the correct size of heat shrink tubing slide over wire and solder in the new diode slide the heat shrink over the connection and heat with an actual heat shrink gun or borrow mama's blow dryer. Do not use a cigarette lighter to heat the heat shrink tube. Note a 1/4" piece of heat shrink will go down to approximately 1/8" when heated.

[pfrederi 17,959]

10 hours ago, 6bg6ga said:

Ok, lets see if I can help. If you have a 3 A diode that means the diode is rated for 3A and yes a 6A diode will work. It will still be limited to the same current output from the stator. Putting on a 6A diode is not going to give you six amps now. You will still have what is being sent from the stator. It just means the diode will be able to take a higher current until it either shorts or goes open.

 

I can supply you with a standard NTE PN for both a 3A diode and a 6A diode and these are rated at 200 volts so they are good enough. PN for the 3A is NTE 5802 and for the 6A is NTE 5854 or the ECG number would also be either 5802 or 5854.

 

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.

 

If your meter doesn't have a diode function test simply put the meter on the resistance scale and repeat as posted above. One way you will show resistance(high) and reversing the leads will show a open and the diode is good.

Excellent description thank you!!

[6bg6ga 272]

Addition info

 

You can order the following pn"s from Digi-Key

For the 6A diode the Manufactures Pn is P600m-E3/54  Digi-Key PN as follows  P600M-E3/54GlCT-ND      Price is .72 ea

 

For the 3A diode    In5408G  Digi-Key PN  1N5408GOS-ND      Price is .39 EA

[krb 4]

Thanks folks. I only had a little time Sunday evening to start troubleshooting. At all the points I checked (voltmeter, ignition switch, harness connector at engine), I was getting 12.3-12.5v whether idling or with throttle.

 

As I get more time I'll find the diode and check there. Man this thing has way more wires than I anticipated for a "simple" mower!

[6bg6ga 272]

If I were to make a guess I would say the diode from the stator/charging system is open and your getting nothing but battery voltage. I'm going to recommend in addition to the diode replacement that you put an inline fuse holder in after the diode in the harness at a point where you can easily reach it and change it if needed. Its unfortunate that Wheel Horse didn't do this because it would save the diode and open the fuse in event of a short or excessive current draw.

If anyone is interested in a step by step instructional pictorial I would be more than happy to make up a mock harness to show the proper way to incorporate two new diodes and a inline fuse in a harness that will be both functional and attractive so as to not take away from the normal wheel horse wiring theme.

[krb 4]

I tend to agree with your thinking there. Since every point seemed to read the same, which was battery voltage and not the 14.5+ as pfrederi mentioned.

 

Good suggestion on the in-line fuse. Why after the diode and not before? Or does it matter as long as it blows? And what amperage if the system is "3" amps? I don't know the formula for sizing a fuse but could find out I guess.

 

And yes I would benefit from the step by step but I wouldn't want you to go to all that trouble just for me. But maybe if this board has a sticky or something for it that would make it worthwhile?

 

Thanks again for yourall's time and help,

Edited April 19, 2017 by krb
more thoughts

[6bg6ga 272]

56 minutes ago, krb said:

I tend to agree with your thinking there. Since every point seemed to read the same, which was battery voltage and not the 14.5+ as pfrederi mentioned.

 

Good suggestion on the in-line fuse. Why after the diode and not before? Or does it matter as long as it blows? And what amperage if the system is "3" amps? I don't know the formula for sizing a fuse but could find out I guess.

 

And yes I would benefit from the step by step but I wouldn't want you to go to all that trouble just for me. But maybe if this board has a sticky or something for it that would make it worthwhile?

 

Thanks again for yourall's time and help,

I would put the fuse next to the load which is going to be after the diode. In looking at the circuit is would be stator, diode, and then fuse. The fuse if used in this manor should in most cases protect the diode and the stator.

[kybishop 0]

Thanks guys for all the help here.

 

I am attaching a photograph that krb (my brother) took. He will follow up with comments/questions on the photo. Having trouble locating the diode in the wiring harness. 

 

 

[krb 4]

As my brother said, I went through the wires and couldn't locate a diode or anything. At first I thought I had it right off the voltmeter but it turned out to be an inline female connector with a rubber boot over it. I used pfrederi's wiring diagram, which is helpful, even though the wire colors don't match ours.

 

I didn't pull the whole loom out, just traced them. It does have what appears to be a relay (in the upper center portion of the photo) that is attached to the right side of the frame? This doesn't show up in any of the wiring diagrams though. It appears to be original to the tractor. Any ideas?

 

The motor Model is M 10 S, the Specification # is 461521 and Serial # 1630905463

 

Thanks

[gwest_ca-(File Mod) 11,121]

Editing this to correct.

The M engines were first used in 1987 but the 310-8 in 1987 shows a 3 amp system in the operator manual. The 1630905463 Kohler serial is 1986 production.

1988 same 3amp charging system

Garry

[6bg6ga 272]

I don't have the tractor or a model like it but I can tell you there is a diode for each circuit somewhere for a total of two diodes. The diodes change the AC from the stator to DC which runs the lights, charges the battery and so forth. Its looking like the diagrams are simply a conceptual of what is in the diagram and not where it is. If it were me I would start looking at the stator and go from there. It might be in some heat shrink in the harness from the stator somewhere.

 

According to the diagram it s looking like it goes direct to the ignition switch and is a white wire. So, what I would do is take your volt meter and attach the red lead to this wire and the negative from the meter to ground. Start the engine meter on the DC volts scale and look for 12+ voltage. If it isn't there the diode is open and you need to go back toward the stator looking again. If there is DC voltage it is going to pass thru the switch and go to a fuse for the charging system.

 

Note*  If you don't have a meter go to your nearest Harbor Freight or cheap big box store and look for something usable. It doesn't have to be a fluke or something along that line to do what it needs to do for tractor work.

Edited April 21, 2017 by 6bg6ga

[pfrederi 17,959]

I just looked up your spec number...according to kohler you have a regulator (#11) which means it is a 15 amp system. That would change this whole discussion.

 

Has something been changed here?  With ignition switch in run but engine not running do your headlights work???

Edited April 21, 2017 by pfrederi

[kybishop 0]

7 minutes ago, pfrederi said:

I just looked up your spec number...according to kohler you have a regulator (#11) which means it is a 15 amp system. That would change this whole discussion.

 

 With ignition switch in run but engine not running do your headlights work???

Interesting. That may be why we can't find the diodes  

 

This is KRB's brother again. I haven't delved into this with him (yet) but need to. I do know that the headlights have not worked for as long as we have had it. The non charging issue is recent but the lights have not worked for many years, 15 years or so. 

Quote

 

 

Edited April 21, 2017 by kybishop

[pfrederi 17,959]

The reason I asked about teh lights...if it was a 3 amp unregulated system the lights work directly off the stator on AC current...but that only works when the motor is running.  The 15 amp regulated system the lights are run off the battery and will work with engine off.

 

Anyway look over the motor (post a picture of it) look for a matchbox size rectangle with a 3 wire plastic plug in one side.  It will be mounted to the air shroud and held there by 2 bolts...that would be #11 teh regulator.  (I only have 2 cylinder magnums so i can't be more specific as to location

[6bg6ga 272]

Good Find!! or Good Catch.

 

Regulator has AC from stator and DC out. Simple, Meter from DC out to ground nd see what you have. No output? Meter the AC from the stator with wires disconnected from the regulator and see what you have. No output? Meter leads from stator  and from stator leads to ground.

[pfrederi 17,959]

This is a 15 amp regulator on a 2 cylinder magnum...your wold look the same but would be mounted i a different place. But some palce on teh air shroud as it needs the cooling airflow....

Edited April 21, 2017 by pfrederi