JD LX277 PTO bolt keeps breaking off

JAG79

Forum Newbie
I bought it used 8 years ago. Bolt broke first time 3 years later. 4 years later bolt broke again. Bolt broke again a year later. Any ideas what could be causing this?
 
Waiting on the "go buy some grade 8 or tungsten carbide bolts" crowd LOL. (y) Maybe some ARP 9000 wonder bolts.

Sounds like the bolts are not tight enough. Mowers have a ton of vibration and get bumped around during mowing. Buy new bolts and orange thread lock them in. Proper torque spec might be a good idea.

Also look for dead siezed spindle bearings or idler bearings causing extra blade load.

Deck might be clogged with who knows debris.
 
Usually those 7/16"-20 X 3-1/4" screws are grade 5. Also are torqued to 55 ft-lbs per the service manual. many hardware store sell lower grade screws.

Here is how to tell which screws are which.

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Waiting on the "go buy some grade 8 or tungsten carbide bolts" crowd LOL. (y) Maybe some ARP 9000 wonder bolts.

Sounds like the bolts are not tight enough. Mowers have a ton of vibration and get bumped around during mowing. Buy new bolts and orange thread lock them in. Proper torque spec might be a good idea.

Also look for dead siezed spindle bearings or idler bearings causing extra blade load.

Deck might be clogged with who knows debris.
Each time I have gotten the replacement bolt from the dealer. It actually looks like grade 8 markings. Also am torquing to 55 ft lbs.
 
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