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Old 07-10-2008, 10:31 AM
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groundsmechanic groundsmechanic is offline
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88 JD 48" Walkbehind Hot Soak No/Slow Start

I just had to go pick up our 1988 JD Walkbehind mower because it either won't start or takes 15-20 pulls to get started after it has been used for a while. It has a Kawasaki FB460V motor.

This thing has been nothing but a problem since I started here two years ago.

I clean the carb at the beginning of every season, all the fuel lines look good. Unless there is something in the tank clogging the outlet or filter, I am leaning toward a carb problem.
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Old 07-10-2008, 12:31 PM
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I took the mower out and mowed with it a bit and brought it back in, shut it off, and tried to start it. It started on the third pull. Then I shut it back off and it will not start. I took the plug out and grounded it, no spark.

I have had problems at the beginning of every season with it having a no spark situation. In the end, it ends up that I remove the flywheel and clean the stator and the inside of the flywheel with some emery cloth. Then it has spark. No I starting to think it is the stator itself. Getting hot and going bad somehow.
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Old 07-10-2008, 01:46 PM
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Phil G Phil G is offline
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Quote:
Originally Posted by groundsmechanic View Post

In the end, it ends up that I remove the flywheel and clean the stator and the inside of the flywheel with some emery cloth. Then it has spark. No I starting to think it is the stator itself. Getting hot and going bad somehow.

Just a thought, if you are going to dismantle and check the stator make sure you check the air gap between the stator and the coil pickup. I think it should be about 8 thou'. Maybe check the manufacturer's web site to confirm. A rough guide to set the gap if you've no gages, loosen the securing bolts on the coil. Place a piece of card (about the thickness of the box spark plugs come in) between the coil and fly wheel. Rotate the flywheel until the magnets grab the stator and clamp the piece of card. Now tighten the coil fixing bolts and slowly rotate the fly wheel and guide out the piece of card you used to set the gap.
Fit new plugs and away you go

Good luck Phil
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Old 07-10-2008, 02:22 PM
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groundsmechanic groundsmechanic is offline
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I guess what I call and you call the stator are two different things. John Deere calls what I am calling the stator, the alternator.



I call the part that is under the flywheel the stator, the part outside the flywheel is the coil.

I clean the ends of the stator every season to fix the no start.


BTW, John Deere shows the "stator" as being a complete circle, this one is less than half. There are other bolt holes, but no broken pieces and it looks whole.
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Old 07-10-2008, 02:53 PM
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Also, is there a way to test these? I have heard these go bad. That could explain the no spark.

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Old 07-10-2008, 03:20 PM
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You're right, it's the gap between the coil and the magnets on the flywheel that should be about 8thou gap. Guess we talk the same language, but different
That other small item with the tab on, where's that located? Something for the earth circuit?
I have had machines where the coil has a short in the winding and does not produce full voltage. If you've got a local guy who can test it, it would be money well spent.
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Old 07-10-2008, 04:57 PM
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Just realised, yours is a 1988 machine. In all probability it had contact breakers fitted to the ignition system and that small black unit is the conversion module. They should only be a few dollars to replace that, but, still get that coil checked out, it's 20yrs old. One thing to remember is that although electronic ignition is more reliable it does need a cranking speed equal to 300rpm to generate a spark.
Keep at it
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Old 07-10-2008, 11:04 PM
kawasaki1 kawasaki1 is offline
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the little electronic device is an ignitor. if it, or the coil goes bad, no spark.

the older kawi's like yours have them mounted on the right side of the engine usually right in front of the dipstick tube. the newer models that use them have them built into the coil.

i suspect your coil is breaking down when hot. when the ignitors go bad, they usually quit for good.

the stator under the flywheel has nothing to do with producing spark.
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Old 07-11-2008, 07:33 AM
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Quote:
Originally Posted by kawasaki1 View Post
i suspect your coil is breaking down when hot. when the ignitors go bad, they usually quit for good.

the stator under the flywheel has nothing to do with producing spark.
I thought I replaced the coil last year, but maybe not. I will order one anyway, it is only $50 or so. Cheaper than that ignitor.

It is kinda weird that the mower won't start unless I clean the rust off the stator ends and the inside of the flywheel if it has nothing to do with spark. I guess that is why JD calls it an alternator.

Thanks all.
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Old 07-11-2008, 09:12 AM
kawasaki1 kawasaki1 is offline
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the coil is probably cooling off while you're cleaning the magnets.

check the ground wire for bare spots/shorts while you have it apart.

one of life's great mysteries is why a coil is about $50-$60, and an ignitor is $50-$60, but a new style coil with an ignitor in it is about $75-$80.
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