About to buy a wheelhorse, trying to get a jump on troubleshooting.

[Influencer88 3]

So I've been in the market for a used riding mower since I moved and now my yard is just too big to push mow. With life I haven't had the extra cash to pony up for a new mower and have had trouble finding a good used one at a fair price.

 

Fast forward to yesterday, got a call from a buddy of mine who says his brother has an older Toro Wheelhorse that needs a starter or solenoid, won't crank so towards the end of last season he bought a used zero-turn.

 

I rode out there with my buddy and looked at it, I won't lie, its in rough shape cosmetically. The shroud over the blower is missing, as well as the shroud over the pulley at the front, battery hold down bar is missing, the battery is currently held in with zip ties.

 

So, I'm figuring the battery is dead but I try anyway, first thing I notice is the brake definitely needs to be adjusted, no big deal. So turn the key and nothing. No click, no anything. I expected that. I brought a screw driver to arc the solenoid, absolutely NOTHING. Ok, battery is probably toast. I pull my car around, hook the jumper cables up and she turns right over with the key. So solenoid and starter both work, just a dead battery. Took a minute of cranking it before she started but she sat for a year so I figure a little trouble cranking is to be expected.

 

The battery was new, he replaced it when he first had trouble with it cranking. I'm thinking its a charging issue, but not one that I've found on the forums in my searches. Most of the posts I've found is the mower runs until their battery is dead then it dies. With this one, if I jump it off it runs GREAT until I turn it off and then absolutely nothing. Jump it off again and she runs fine.

 

I've looked at the charging diagrams, looks like the charge from the alternator runs through the ignition switch before going to the battery?

 

Not sure of the year but it's a Wheelhorse 312 8 Speed model number 73362 with a Kohler engine. It does have the Oil Sentry.

 

How many fuses should this model have in the fuse block? I only saw 2 fuses in there. It was getting dark when I looked at it so I couldn't look in great detail.

 

One thing for sure, once she started she ran great, he had a patch of grass under the trampoline where he didn't move it so I cut that for him, has a good cut. All gears work in both hi and low.

 

Best thing of all? Picking her up today at the tune of $75.

[SethL1984 38]

Good work! Sounds like you've already got a handle on what needs' doin'! the 312-8 is one of the most popular and gone to models. There're a few threads in the Electrical forum that deal with these issues directly. 

And if you can make it to Ardentsville in June you should be able to get all the parts you need!

 

Edited May 6, 2014 by SethL1984

[SousaKerry 500]

 

Try this file on for size should help you track down your mystery problem

 

 

and as always

 

[Influencer88 3]

I didn't see any threads that dealt with the issue the same as what I'm seeing, but it might just be some information I'm looking for is omitted.

 

The main difference (in the threads I found) with no charging is the ones I have seen the mower isn't charging the battery so as soon as the battery is dead the mower dies. My problem is the mower runs fine as long as I jump it, but it doesn't charge the battery at all.

 

At any rate I just got it home and am going her cleaned up some so I can see what I'm dealing with. Tomorrow I'll cut the grass with her for the first time, then I'll start tackling the charging issue. Who knows, might be a shorted wire or a bad fuse, just gotta dig in and find it!

 

The friend that helped me pick it up was unusually quiet when we were picking it up, it wasn't until we got back to my house that he started talking. "You know what this thing is worth right? You stole it for $75"

 

I already downloaded the transmission manual, owners manual and demystification guide. Thanks for the link though!

 

I'll get a couple pictures up, but here's one I snapped last night when I went to look at it. Like I said, she's in rough shape. I'll be doing what I can here and there to get her more up to par.

 

As you can see, PO has zip ties holding the battery in.

 

[bmsgaffer 2,043]

Since you have the magnum engine, it will run all day long without a battery... Assuming you can get it started. (magneto ignition)

 

The threads you read were from an engine with a battery ignition, which if its not charging will eventually die when the battery does.

 

Did you ever try charging the battery on a charger? Jumping it will not charge the battery very much.

 

I think you have a bad rectifier/regulator as well as a bad battery (deep discharge state over even just one winter WILL kill a battery). You can try putting it on a high quality charger/desulfator but I doubt it will last very long. I would just bite the bullet and get both.

 

That tractor looks great! At least from 10 feet I see no major issues. You stole that thing!

[Influencer88 3]

The safety switches need to be cleaned, one crack in the seat, all moving parts need to be greased but overall nothing horrible. Blades definitely need sharpened.

 

It starts fine, is there any preventive maintenance I should perform for the magneto ignition?

 

Gotta dig in and test the stator and RR to see how they are doing, I do know that at the battery there is zero volts while running. Once I know the charging issues are fixed I will buy a new battery.

 

Oh, should I mention, use to take me a little over 2 hours straight to cut the grass, I decided to cut it today to see how it performed before messing with switches and fuses and such. Took just over 30 minutes. I don't have a big yard, but its big enough and uphill so push mowing is a chore.

 

As for trying the battery on a charger, not yet. Will be placing on charger tomorrow when I start to clean everything up.

Edited May 6, 2014 by Influencer88

[boovuc 1,090]

If that battery is a Walmart battery, that in itself may be the problem.

With the motor running full open, get a volt-ohm meter and with the meter on Volts DC, put the red lead on the positive battery terminal and the black somewhere to ground on the tractor frame. If you read just a hair over 12 volts to 12.7 volts or lower, it isn't charging. If you are getting 13 to 16 volts, it's charging. If you are getting 16+ volts DC, the battery may be toast and will need replaced.

[Influencer88 3]

If that battery is a Walmart battery, that in itself may be the problem.

With the motor running full open, get a volt-ohm meter and with the meter on Volts DC, put the red lead on the positive battery terminal and the black somewhere to ground on the tractor frame. If you read just a hair over 12 volts to 12.7 volts or lower, it isn't charging. If you are getting 13 to 16 volts, it's charging. If you are getting 16+ volts DC, the battery may be toast and will need replaced.

The battery shows zero volts with or without the mower running. I think maybe a combination of shorted battery and blown fuse?

Other than the two fuses in the fuse block, where else can I expect to find fuses?

[bmsgaffer 2,043]

Zero volts will be a dead battery AND rectifier/regulator

 

One may have killed the other. If you put the voltmeter on AC and measure the two black wires coming from under the flywheel you should see over 30V. That will tell you the stator is good. I don't think there is a fuse in the charging system, so dont' worry about fuses. If it starts and runs (and you get lights when you have a good battery and rectifier) all fuses are good.

[Influencer88 3]

I guess I'll dig in tomorrow and test it all out. Where would I find the regulator?

[bmsgaffer 2,043]

ebay, or PM a vendor on here: Kelly

 

or there are others around. You can post in "Wanted" and they usually check there within a couple of days

[Influencer88 3]

Cool. I'm fine with jumping it off if it comes to it, but naturally I'd like to fix it. From what I've read the wheelhorse will last me a long time.

[Influencer88 3]

Ok, I have gotten the serial and model numbers.

 

Mower Model Number: 73362

Serial #: 49-01022

 

Deck Model #: 78345

Serial #: 49-01375

 

Still having trouble tracing the wires to where the RR is. Gotta get things cleaned up in there to be sure but all I've found is a connection with a purple wire coming out from behind the flywheel. Might be missing something, still looking.

[gwest_ca-(File Mod) 10,508]

With 0 volts your battery is completely dead or shorted. I would not run it again until you have a good battery installed. You chance doing damage without it. Even a battery too dead to do anything has 11 volts.

 

Here is the operator manual and wiring diagram

Illustrated parts list

 

Mower deck

 

Garry

[Influencer88 3]

How about where the wires for the RR and stator are located?

 

Normally I'm pretty good about figuring out wiring, but for some reason this one refuses to sink in.

 

 

This is the only plug I can see coming out of the engine.

 

 

Here we have the solenoid, two relays and fuse block. There is NO power at either fuse.

 

 

Control panel, no power anywhere here either.

 

 

AAAAAND this little gem, no clue what it is at all.

 

For a little more info, here's the engine information as well.

 

Kohler Magnum 12

Model: M12S

Spec: 471527

Serial: 2409015673

 

The main thing that's confusing me is I can't get a power reading from anything. The entire mower is a black hole for voltage.

[gwest_ca-(File Mod) 10,508]

The last picture is the voltage regulator in the blower housing. There is a hole under it so the air off the flywheel fan can cool it.

 

So you have no power anywhere. You have a battery installed? And what is the voltage across the battery posts?

 

Garry

[Influencer88 3]

So that 3 pin connector is for the voltage regulator? Well that atleast gives me something to start with.

 

I'm not a rocket scientist, well, I was as a kid but they kept crashing or blowing up so I gave it up. The 3 pins on the regulator should all connect in that connector, correct?

 

Reason I ask is when i pulled the connector off earlier, the middle pin was bent down and not connected. I wonder if it was grounding out and that's what did the charging system in.... Guess I'll be testing those points tomorrow. As a glimmer of hope, when I connected it back up there was a little arc so there's atleast SOME power getting to it.

 

On another topic, does anyone have a picture of the belt that should go from the PTO clutch to the deck? The belt that was/is on there looks like an automotive belt.

 

Also, no voltage with a battery installed/no voltage while running. Battery is on charge now, will test again tomorrow. Voltage before charging was at 11.5

[gwest_ca-(File Mod) 10,508]

Mower deck manuals. You may have a different width of cut  and outlet but should explain the belts

 

There should be a wire from the + battery cable on the stater solenoid going into the fuse panel to feed it. Then the fuses link that feed to the various circuits. The spark you saw at the voltage regulator may have blown a fuse.

 

Two of the wires on the regulator are for the AC leads coming from the flywheel stator. The 3rd terminal is the rectified and regulated DC current to the tractor.

 

Here is a link to the M12 Kohler service manual

http://www.wheelhorseforum.com/files/file/29-engine-kohler-magnum-m-8-m16-sm-tp-2203-apdf/

It explains the charging system.

 

Garry

[Influencer88 3]

Thank you. I'm very frustrated, like I said normally I can figure out wiring pretty easily but for some reason this mower just locks my brain up. That and with years of neglect every time I start to look at the wiring I notice something else I need to do and there goes my concentration.

[Influencer88 3]

Now that I know where the RR is I could test it, I never would have found it bolted on the cover like that.

 

So, here's what I've got:

 

Two wires on outside of regulator plug, which according to the diagram should be the AC lines coming from the stator. At low idle I'm getting around 20V, high idle I get around 40-45V. This should be ok, right?

 

WITH the battery connected and engine running I tested the RR, per Kohlers troubleshooting steps. I tested at the B+ lead and got 13.8V, the manual stated to apply load and if the voltage increases that the RR is good. I turned the lights on (again, per the manual) and voltage increased to between 14-15V, so according to that the charging system is good.

 

What threw me off is if I disconnect the battery I get no voltage at the RR B+. Does it have to detect a load to work?

 

Whoever messed with the connector before me definitely bent the spade connector for B+ down by accident and I'm confident that's what started the issues. Maybe I'm lucky and bending it back and making sure its connected I've fixed the problem and won't require new parts.

 

Unless anyone has another suggestion or insight into the issue, I suppose I'll keep an eye on the battery and charging system over the season and if I have no more issues I'll consider it good to go, if I do I'll go ahead and replace both battery and RR.

[gwest_ca-(File Mod) 10,508]

The regulator must see battery voltage before it can regulate the current from the stator to turn it on so to speak. A good test to do that is not often discussed is to turn the key to RUN with the engine NOT running, check the voltage at the regulator +DC terminal and compare it to the voltage across the battery posts. It should be the same and if it is the regulator is seeing the battery voltage so it knows what to do. Dirty connections can cause a difference so the regulated voltage may spike trying to compensate. This test also verifies that the path the current takes to the battery is not compromised.

 

Sounds like you are good to go.

 

Garry

[Influencer88 3]

Is this a difference between single phase and three phase charging systems or a difference between magneto ignition and battery ignition? Reason I ask is on my motorcycle or car I can test the output easily by disconnecting the battery and measuring the voltage from the RR, so it doesn't need to "sense" the power from the battery first.

 

I guess this makes sense as the RR is basically there to charge the battery vs on a battery ignition system the RR provides voltage for the entire system as well as keeping the battery charged.

 

Well, good thing I found this awesome forum and thank you for all your help Garry, I was basing all of my diagnostics off of systems I had worked on before and this one is different!

[bmsgaffer 2,043]

That's the difference between tractor and automotive style rectifiers/regulators .

 

Is the battery holding a charge after you threw it on a charger? If it is still really low I would replace it or you risk burning out the regulator trying to charge it.

 

If it is, then you are good to go! Good catch on the spade terminal, that's an easy (and cheap) fix!

[Influencer88 3]

After charging the battery it is holding steady at ~13-14V, using an analog Multi-Meter so can't be exact, but I'd say its pretty much 13.7V. I've started the wheelhorse about 7-8 times today testing things here and there and every time I do the poor mans load test (hold meter to battery while cranking), battery doesn't drop below 12V and jumps right back. Charge is staying right under 14.

[bmsgaffer 2,043]

Sounds like you've got it licked!

 

Get a real hold-down for the battery and you will have a nice looking, long lasting tractor there!