PTO bolt came out ??

Hayward51

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My friend asked me to help figure out his Scag quit mowing. After looking at the clutch, it was obvious. The bolt holding the clutch on the crankshaft was gone and clutch had slid down off the key. We looked all over the yard, no bolt found. What are the chances it just backed out ? Or stripped out ? If it stripped out, what is the best course of action?
 

StarTech

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Might get lucky and it just backed out without damage the leading threads. These must be torqued to spec or they will do this. No impact install either.
 

Hayward51

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Might get lucky and it just backed out without damage the leading threads. These must be torqued to spec or they will do this. No impact install either.
Thanks for the positive reply. I'm headed out to pick up another bolt and hope for the best !
 

StarTech

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Just make you get a Grade 5 if 7/16 or grade 8 if 3/8" If M10 then 8.8 or 10.9.
 

Tiger Small Engine

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Just make you get a Grade 5 if 7/16 or grade 8 if 3/8" If M10 then 8.8 or 10.9.
I have seen 3 PTO clutch bolts back out and fall out in last two years, it happens. Install new bolt with Loctite thread locker and torque to specs, probably around 50-55 foot pounds.
 

Hayward51

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Thanks for all the advice. I have a new bolt and washers.
 

slomo

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Just don't go overboard and install some super hard bolt. Later on if someone has to drill it out........ Get the OEM bolt/s.
 

Hayward51

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I did buy the bolt from the local Scag dealer ($5. just for the bolt). Threads were OK but it broke one of the wires when it slid down the shaft. I spliced the wires back, installed clutch and it doesn't lock in. I'll pull the clutch and start testing again tomorrow. Hopefully, I can find something and salvage this expensive part.
 

Tiger Small Engine

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I did buy the bolt from the local Scag dealer ($5. just for the bolt). Threads were OK but it broke one of the wires when it slid down the shaft. I spliced the wires back, installed clutch and it doesn't lock in. I'll pull the clutch and start testing again tomorrow. Hopefully, I can find something and salvage this expensive part.
Watch Taryl Fixes all for poor man’s PTO clutch repair when two wires pull out of clutch. It involves driving a screw down into broken connections to secure wires.
 

Hayward51

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Thanks for your replies. I lucked out. The wire was also pulled back in the connector and wasn't making contact. All is back working !
 
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