drive motor bolt keeps backing out

[earlyriser]

Hi all. I have a 2007 S160 and a couple seasons ago I removed both final drive motors and completed a seal replacement on both. They are held on to the machine by allen head bolts. One of the bolts continues to come loose after working the machine hard. I imagine the drive motor getting hot along with constant vibration is a double whammy. I have used red permatex and it still happens. I have ordered both Loctite 266 and 2760 which I will pick up on Friday. Any advice is appreciated. Torqued to recommended ft lbs (95 I think). Thanks

 

[earlyriser]

anyone?

 

[foton]

anyone?

lets see if the locktite works the only other thing and it would take some clearance to do it is to used a longer hardened bolt (almost bottom it out) and use it as a stud but have a lock nut on the threads and use it as a jam nut . remember before using the locktite clean the threads with a solvent. is there a chance that something is bent and causing a vibration that is loosening thing up? good luck

 

[craigb93]

I had a drive axle bolt on my BMW that backed off a time or two even when carefully torqued. Left me on the side of the road once. The flange only has 5-6 threads thickness. Solved it by drilling the bolt heads for a safety wire to the adjacent bolt. Problem solved. -Dick

 

[flyerdan]

I had a drive axle bolt on my BMW that backed off a time or two even when carefully torqued. Left me on the side of the road once. The flange only has 5-6 threads thickness. Solved it by drilling the bolt heads for a safety wire to the adjacent bolt. Problem solved. -Dick

Safety wire is often the best way to secure something where only the bolt head is visible. If you can have a strip with bend up tabs between bolts like a small engine muffler, that could work but requires a flat surface between bolts.
Safety wire works in a lot of places, and you can get NAS bolts in NC thread that have the heads drilled for wire already.