# What are these broken magnet pieces? (Battery not charging)



## denno (Jul 10, 2009)

OK, that title means....
Craftsman 917.255450 riding mower, 14 HP Kohler engine. On the rim of the flywheel is a magnet, looks intact, brushes by what I guess is the alternator. However, there are broken pieces of magnet all over the place under the hood (and sticking to the hood).

Meanwhile, the battery does not charge. Mower will run from a jump, until it is shut off.

S'pose these two things are RELATED?

Is there a second magnet assembly on the bottom of the flywheel, separate circuit for charging battery? (Schematic doesn't look like it ---- not that I speak schematic...)

Can someone get me started with this diagnosis and repair?


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## 30yearTech (Sep 14, 2006)

There is a magnet underneath the flywheel that creates the field to energize the alternator windings also located underneath the flywheel. You will have to remove the flywheel to see whats going on under there. Some of the magnets that are bonded to the flywheel may have come off. 

Let us know what you find.


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## denno (Jul 10, 2009)

Thank you and good morning.
Another nudge to my learning curve, then......the side-mounted magnet and the coil it interacts with is just the spark generator? (Schematic seems to show lines running from the same place to the lights and also back through the diode/charging system to the + side of the battery --- I guess "schematics" are not "wiring diagrams").

OK, so I'm going to pull the flywheel. (That might be my farthest exploration into a mechanical device so far). 

Practical question --- am I going to need a flywheel puller?

Impractical question --- Sears reports this engine as discontinued (on their parts site). I suppose I should (and will) check that with Kohler. I suppose I could scare up a flywheel for it somewhere anyhow. Hooray for the Internet!


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## 30yearTech (Sep 14, 2006)

Engine is not obsolete, parts are still available for it. Use the model and spec number CV14S-1451 to locate parts for your engine. It shows up on Sears parts direct site for me.


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## denno (Jul 10, 2009)

Okay, I like your result with parts direct better than mine.

Meahwhile.....about that flywheel. I took off the fins (and only dropped one of the screw bushings in the grass) just to get them out of harm's way. Then I had at the central bolt. It is not budging so far. 
Question: seems that would be a right-hand screw, so tightening is naturally against the direction of turn when the motor is running. But is it possibly left-hand?
I have sprayed a loosener on it and given it pretty good pressure with a shortish socket wrench in both directions. No sense that there is any give at all either way. Until I am sure which hand it is, don't want to extend my leverage and give it REAL pressure.

Also, I am sticking a screwdriver between two teeth on the flywheel and bracing against the shaft of the starter. Probably a better/safer way to hold the flywheel against the wrench?

Any advanced bolt persuasion advice? Oh---hammer drill, maybe?

Meanwhile, I am opening another thread for my other mower, different problems. Gotta get ONE of these working or call in the neighbor with the tractor mower!


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## 30yearTech (Sep 14, 2006)

The retaining bolt for the flywheel is right hand threads, so it will come out counter clockwise. It's torqued to around 50 ft lbs so it is on pretty tight. An impact wrench will get if off pretty easy, it's possible to break the teeth on the ring gear holding it like you are.


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## Rentahusband (Aug 25, 2008)

Did you get the flywheel off?
Dean


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## denno (Jul 10, 2009)

Nope. Gonna have to borrow an impact wrench/drill/whatever. Probably can't get back to it till Sunday.
Other way would be use a biggish wrench and extend the handle w/pipe, get some real leverage; but something might well break. 

BTW, is there a right way to brace the flywheel against the wrench? I've had weed whackers that had a couple holes to line up and a pin to insert, for instance. 

Despite trying to do this correctly, I AM assuming that a new flywheel is in order; don't suppose one replaces the magnets.


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## 30yearTech (Sep 14, 2006)

You could use a band type wrench to hold the flywheel, although an impact will take the bolt out without any help holding the flywheel. 

I have never had luck getting the alternators to work again after reinstalling the magnets, but I have been told by others that they have had success. There is a good possibility that the alternator may have some damage from the loose magnets.


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## cajunh2s (Apr 19, 2007)

Denno

If you don't have a flywheel wrench....you can try jamming the blade under the deck..with a 2x4 or something...not the best thing in the world to do for the crankshaft.....but sometimes desperate measures are taken...lol

and the wax trick may help that stuck flywheel......take some bee's wax.....and melt some on top the nut on flywheel.....making sure you hit those top threads...let set a few minutes and harden....then break that nut off no problem...,,what happens is...the liquid wax...seeps down into the threads on the flywheel....as it dry's it expands breaking away rust and corrosion....and the wax..also works as a lubricant...cool huh

you can do this with a socket and breaker bar...if no impact wrench is available...

good luck
cajun


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## denno (Jul 10, 2009)

Thanks for input to the Nut Challenge. Tomorrow I will see which is easier to find----a wrench or beeswax.


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## Rentahusband (Aug 25, 2008)

Impact wrench would be the best to avoid damaging the flywheel. Usually the flywheel is stuck to the crankshaft due to the tapered fit, what I do is put the nut back on the crankshaft so the end of the crank is even with top of the nut. Lift up on the flywheel and *"tap"* the end of the crank with a hammer. 
Dean


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## cajunh2s (Apr 19, 2007)

Denno

The wax is pretty easy to find....most super markets or a wal-mart will carry it
look where the candles are...or in the hobby section....this is the stuff they use to make candles with..

cajun


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## denno (Jul 10, 2009)

None of my garagejock neighbors has an impact wrench, so I'm gonna get one on eBay and will have a report for y'all in a few days. 

Not to ignore the beeswax thing, but I'm gathering an impression that it is likely not so much rust as that these bolts are notorious for being tight due to the rotation, the long time between loosenings, and the conical configuration of the shaft. Or something.

Oh --- other thing is that I've had it explained to me that this is a bolt with an attached washerlike flange, as opposed to a nut that leaves the bolt threads exposed; so wax can't get where it's needed. Phoo!


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## denno (Jul 10, 2009)

Stuck!
Managed to borrow an impact wrench, removed the bolt.
Had a 3-prong puller, not wide enough. Was also advised by friend not to mess with the rim of the flywheel anyhow. Tried a couple of prybars and banging on the middle --- actually, on advice, on the reinserted bolt. No action! 
Can see how I could (find or) construct a puller that worked on bolts in threaded holes in the flywheel. But I think I am gonna take the thing to the friendly local ATV shop and beg a favor. Or let my wife do the chick thing and beg the favor....
That'll be probably Friday, so talk to y'all then.


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## denno (Jul 10, 2009)

Update: That shop will pull the flywheel for me once I get it down there...tomorrow?
Meanwhile, I got the battery checked and although new this season it is a dud. 

Should I hold the phone and (reassemble the flywheel vanes and whatever else) and put a good battery in and see if it runs it dead? Or, lemme see....once it is running, can I put my multimeter (assuming I can figure out how to use it) on the battery and learn whether it is charging or discharging? Or the output of the alternator (if I can figure out which wire that is...)

Could there be anything in running the mower or in attempting to start it, etc., that would kill a battery?


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## Deathrite (May 21, 2009)

ONCE YOU GET A NEW FLYWHEEL INSTALLED.. you can check for charging by starting the mower (anyway it will) and then putting your DMM (digital multi-meter, analog [one with the needle] will also work) in DC VOLTS mode. if its is manual range set pick the first range OVER 15 volts. should be 20 or 30. make sure the leads are plugged into the correct spots (you would be surprised...) and place the red lead on the positive post of the battery and the black one on the negative post of the battery. you should see a reading over 12 volts. 13 to 15 volts is what we commonly see. this means the charging system works. if you see only 12 volts or less... charging system is likely dead.


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## denno (Jul 10, 2009)

And thanks for that primer.
Just for the sake of discussion, since I have not got the machine down the hill to the shop yet....
Fellow at the shop said he once found that there were 4 magnets on the flywheel, one having come out or broken up or whatever.....he removed the one opposite [gotta say, I can't imagine how there could be wobble from a missing magnet --- I can't MAKE the dang thing wobble with a hammer and two crowbars!] and the alternator ran fine on two.

If I were going to be exhaustive, then I would reassemble everything and see if the battery were charging --- since it is now known the battery was no good. S'pose I should look up how much a new flywheel costs.

Just musing, here, while I get to the next step.


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## 30yearTech (Sep 14, 2006)

If you remove any of the magnets, it will affect the output of the alternator, if the alternator will work at all.


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## denno (Jul 10, 2009)

Well.....finally got someone to take off the flywheel for me. Correct tools, took 20 seconds.
Not a shred of magnet left on it. Stater also bunged up some. Retail for stater and flywheel said to be around $300, not a good option for me. [Haven't started looking for alternative markets, used parts, whatever, yet].
Is there any reality to replacing the magnets and using the old flywheel?

At least, with all these investigations and failures of various parts, I surely know how to look in more detail at a used mower now.


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## 30yearTech (Sep 14, 2006)

Unless you need the alternator to do more then recharge the battery, just run it without the alternator. You can periodically charge the battery with an external battery charger. It will not affect the running of the engine at all.


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