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Discussion Starter · #1 ·
I got a JD 180 with a attitude! Just cause I use it and 'gator blades instead of a bush hog shouldn't make that much difference - wouldn't think!

Was hogging a couple of weeks ago when the blades went on vacation. Twas late, so quit for the day. Couple days later fired it up, hit the chew'em up switch and the blades went to work - for about 40 seconds. Hmmmmph. Shut it down.

Later one evening when didn't have anything else to do (Yeah, right), tried it again. Blades ran for maybe a minute, then I cut them off. When I hit the switch again, nada - motor didn't change pitch.

Tech manual sez you're supposed to be able to hear the PTO 'click' if you hit the switch with the ignition on (no motor running). MY ole' switch makes so Dang much noise when I cut it on you couldn't hear a cherry bomb in your back pocket if it went off at the same time! So much for that helpful comment.

So, I deposited my 68 year old spry butt down on the comfortable concrete and eyeballed the clutch - didn't see anything of immediate concern. Clutch frame rotated freely throughout the slot travel as allowed by the stop pin sticking down - maybe an inch or so.

Now, more about that stop pin ...
Started the motor while I was still horizontal, and reached up and hit the switch while watching the clutch. I saw it rotate to the stop point and thought I saw a spark at the stop pin!

Moved the light away and - Lordy, there was a whole bunch of sparks justa dancing around that stop pin! Strikes me as not being quite right -know what I mean, Vern?

Watched the show for a while, then offed the switch and shut down the motor. Turn the ig switch on again, hit the gogo switch. Reached up and moved the clutch around - back and forth - didn't see nary a spark! Nuttin! And it was dark up there!

Well, ain't what I expected. Poot switch off, start motor, Poot switch on, and the fireworks start again! Well, Crap!

Ok, Wise Souls, help me decipher this strangeness! First off, kinda makes sense that the PTO coil has sadly found an unwanted connection to the clutch frame. I saw the dash lights dim a bunch while this testing was going on - dropping close to 3 volts at the PTO connection from battery + and the coil surface gets downright hot pretty quick.

Now, seeing as how the crankshaft IS a least somewhat connected to frame ground through the bearings, piston rod, rings, etc - Granted, not an inspector grade connection but still SOME - why was the current not going thru the crankshaft to ground but instead puttin on the light show at the pin? (Never woulda seen it in the daylight tho!)

And, why didn't I see any sparks when I was rotating the clutch frame by hand with the switch on? Didn't see NONE! That's what gets me!

All ideas will be greatly appreciated!:dunno:
(Plus a cheap PTO clutch! Hint hint.)

Friendly Fred
 

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Hello, and welcome to the forum!

Now without being there, I'll try and get this right. When you turn the power on but the engine is not running the clutch should not engage anyways do to the safety switch, so there will not be any voltage present at the clutch.

Honestly, even with the engine running, you should not be able to engage the PTO unless you are in the seat, once again, safety presence switch.

Sounds to me like the clutch is shot. It is an electromagnetic switch and if the contacts inside the clutch have completely worn out it could be shorting out.

Without seeing it, it might not be electrical sparks (arcs) but it could metal sparks from a disintegrating sprag gear or locking mech in the clutch. The part that makes it lock in place for power to the deck.

As far as a cheap PTO, you'll have to shop around like EBay or other places on line, These guys are pretty good with engine related items for me, tewarehouse.com. Although you will have to make your own choice as we do not endorse any particular company.

I hope I understood you correctly.
 

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Discussion Starter · #3 ·
Hey, Five Points -

Thx for the reply.

Actually, listening for the PTO 'click' when the PTO switch is cut on WITH the ig switch in the on position *and the motor NOT running* is one of the diagnostic steps (Section 240-05-2 Item #6).

What you were probably thinking is whether or not the engine will actually start with the PTO switch turned on. It should not do that. That diagnostic step is the 'PTO Neutral Start' check (Item #4).

I'm fairly certain these sparks are electrical - the stop pin location is away from the main body of the clutch itself and protrudes through the bottom flange of the clutch. There are no moving parts (rotating) at that location other than whatever vibration (movement) of the flange being torqued against the stop pin.

I forgot to mention that the seat safety switch is not in the picture here. The original seat had a switch on the bottom (that worked) but was replaced with one that had no switch.

That connector is just laying under the seat in an electrically 'open' state. That implies that the seat switch would be a normally closed type with no weight on the seat (unless something else is screwed up with the circuitry).

The general conclusion is that the PTO asm is trashed. JD wants around $279.00 for the clutch last time I checked and eBay has them for $175 or so. Mower is only used infrequently so the cheaper PTO is a logical choice for me.

The only other issue with the mower is it is cantankerous as H... to start. Choke it briefly when cranking and then pull the lever all the way off. Have to keep it cranking till the engine catches and let it putter for 10-15 seconds, then S L O W L Y advance the throttle a bit at a time.

I investigated carb adjustment once for this issue - Man, what a God-awful process they describe! I decided to leave it til absolutely necessary!
 

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Maybe a good tune up is in order. Plugs, filter etc. Try some seafoam in the gas, it may help clean out a little crud from the carb and buy you some time on a carb rebuild.
 
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