Repairs 05 Ferris Blowing charging circuit fuse

guruyouthpastor

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I have an 2005 Ferris IS3000 that is blowing the charging circuit fuse after about 30 seconds of engine running-----any thoughts????? Help!!!
 

oops409

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I had a similar problem. The fuse would blow after about 15 minutes running. Later, it would blow just by turning ignition switch to on. Replaced voltage regulator and the problem went away
 

bertsmobile1

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Get the multimeter out.
Check the output of the rectifier in both AC & DC and between each of the pins and each one of them to ground.
Also check the fuse holder, they tend to get grubby which pushes up the resistance beyond what the fuse can take.
 

fabrizi0

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Had similar symptoms on my Ferris DD 48", Kawasaki 19 HP. Otherwise, never a problem in 14 years.

Recently, the mower stopped dead in the middle of the lawn. That must have been the battery fuse; I wasn't paying close attention at that point. A month later when another fuse blew, I began paying attention! From that point on, fuses blew more frequently, and consistently it was the charging circuit.

Within another month the fuse began blowing immediately. The coil wire resistance to ground was inconsistent - sometimes a dead short, and open at other times. The coil resistance itself was consistently okay (~0.11 Ω).

The charging coil output voltage at speed was 28 - 32VAC, and would source 4 Amp AC when shorted. One time when it was running and coil voltage was good, I put the charge circuit fuse in, and all was okay... until the engine speed was slowed to low idle. Then bang, another 20A fuse - I could see the flash. From then on it blew the charging fuse immediately.

When I pulled it apart, the problem was obvious - a breather chamber cover bolt had vibrated out, was loosely wedged between adjacent coil poles and had been rattling around. That chipped the enamel in a few small spots.

coil w bolt, crop.jpeg


At high RPM, centrifugal force caused the bolt to swing horizontal, possibly still in contact with (bare) wire, but not in contact with the mounting ring. But when the engine slowed to low idle, less centrifugal force allowed the loose end to drop onto the mounting ring, creating a temporary coil-to-ground short. That was the reason for inconsistent results, like coil wire resistance to ground was sometimes infinite, and sometimes zero.

Removed the bolt and of course the short was gone. As far as I can tell, without the bolt there is no coil-to-coil short; no bare spots touch. The bolt may have shorted between coils once based on the scorched enamel on one pole, but it didn't come off the wire.

scorched enamel low res.jpegscorched, flipped, low res.jpg

I don't know which contact was intermittent, maybe both. I cleaned the discolored and bare spots, and coated them with 3M ScotchKote FD, a tough weather-proof coating for exposed electrical wiring. Not pretty; it doesn't smooth well. But it works.

recoated detail 1 low res.jpg

Replaced the regulator, re-assembled, and the battery charges fine. Without the loose bolt in there, I'm pretty sure it will continue working.

Is this what the Kawasaki instructions mean when it says to check that bolts are tight, daily?
 

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calder-cay

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Had similar symptoms on my Ferris DD 48", Kawasaki 19 HP. Otherwise, never a problem in 14 years.

A great write-up with quality photos and attention to detail.

Thanks for posting this!!
 

fabrizi0

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So, now one year later - a full season of mowing, no blown fuses, works fine.

A different electrical gremlin showed up; convinced it was the battery. Apparently got run down over winter from disuse. Come spring it would star the mower, but pulling in the PTO it would stall. I put a battery tender on it; once the mower was used regularly again, the battery tender no longer needed. Maybe 1 more year?
 
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