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Raymond Fisher

Simplicity 12.5 LTH blades disengage when shifting out of neutral

I bought this lawn mower used last year and it worked fine. The safety for the seat has been removed and replaced with a jumped by the previous owner. I have had issues for the past couple months with the blades staying engaged. Before if I would turn the throttle down, the blades would stay engaged. Then they would only stay engaged for a little while. I have verified with a feeler gauge that the clutch is set between 0.010 and 0.012 on all three slots. I removed the clutch and verified that when the PTO switch is engaged that the voltage at the clutch increases from 0 to 21V. I cleaned the clutch, lubricated and replaced, reset the gaps and it cut fine. 2.5 weeks later the blades keep disengaging. With the seat safety off I was able to engage the blades, disengage the tranny and push/pull it to get my backyard. I tried to ride it again, shifted and it shut off. My great-uncle-in-law thinks it is a neutral interlock of some kind, but I can't find a good wiring diagram anywhere for where that might be located or how to test it.

Lawn Mowers
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1 Answer from this member:
Manage My Life
Given what you've described, I'd have to say that the problem is indeed with the safety circuit on your mower. You can contact Simplicity (online or a local dealer) to see if they can get you a schematic for your machine to make the necessary repairs. Since you know that the seat switch has been tampered with, it's very like that that will be where the issue is at.

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by Manage My Life
August 14th, 2013
0 votes
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