Hello. I recently bought exmark 48 from a friend. Mowed fine for hour and half then blades quit turning. Mower ran, only blades stopped. I replaced PTO switch. Ran again. 6-10 minutes, blades stop again. Raised mower and metered pto clutch wiring at plug for 10 minutes and everything stayed engaged. Not to sound like idiot, but is there a switch that is tied to this circuit. I assume pto clutch is sketchy but not sure now....
Exmark Lazer Z 48
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Mower King
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Sounds like the PTO clutch might be bad. When the clutch is bad, it will work for a few minutes then burn out the PTO switch, put on another new PTO switch and it will burn it out also.....and will keep doing it. Get an OHM meter and measure the OHM resistance between the 2 terminals on the clutch, and report back with that number.
Clutch shows 2.3-2.4 ohms. Measuring at plug end.
Mower King
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That is a good reading for a used clutch, unless something else is happening with the clutch, those are good #'s
Clutch activates every time. Problem is it just cuts out after 5-10 minutes of running. Almost like its overheating. Not proper terms I'm sure but... im searching forums for another direction to go if I can assume clutch is good. Any pointers?
Mower King
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I'm not that familiar with Exmark but, If it cuts out every 5-10 minutes and acts like it re-sets itself and works again, kinda sounds like a relay cutting in & out. I would check & see if there is a relay in the PTO Clutch circuit, and go from there.
bertsmobile1
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Is the clutch adjustable and if so what is the air gap ?
When the air gap gets too big, the clutch draws a lot more current to hold the plates together.
When the air gap gets too big, the clutch draws a lot more current to hold the plates together.
I ran mower with pto engaged until clutch disengaged (around 5 min). When pto disengaged (everything else continued to run) I hopped off, unplugged clutch, metered it and read 0 ohms, Open line. Is it possible for clutch to overheat and disengage due to internal failure?
Mower King
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If I read a clutch and its' 1.7 or below, it's bad....but I measure them cold! I say measure it again when cold. Does your clutch have pigtail wires molded into it or do they unplug at the clutch? If it unplugs, unplug it and measure the clutch.
Original cold reading was 2.3 - 2.4. Then I ran it until it disengaged and it ohm's out OL. I'll have to research air gap and whether clutch is adjustable