LMTV Alternator pivot bolt keeps breaking

[Konichiwa512]

In less than 500 miles, I have seen the 8in bolt that mounts my LMTV alternator to the lower pivot point break twice. It happened today near the CAT engine repair place in town. They said I needed a bushing for the aft hinge point. I have a newer alternator, the N1511, and the LMTV parts manual shows the old alternator which has no such bushing. Any parts figure I can find for the alternator does not include the pivot hardware, so that must be considered a truck part. The CAT mechanics were certain that a bushing is supposed to go in the aft pivot like they put them in daily, but I cannot find a part number or any info on this bushing. The CAT guys had a spare that they were going to install, but it was too large. Does anyone have info on these or have one they can mic and send me dimensions on so I can have it machined? The original is somewhere along Interstate 10, or was never installed and its absence contributed to the pivot bolts repeatedly failing.

 

[Konichiwa512]

Well I guess I will answer my own post. Most alternators have a bushing in the rear mount to help ground the case. I don't think mine had one since the time the Army installed my alternator, which has a date of Oct 2012 stamped on it. The alternator was free to wiggle around and must have been what caused the pivot mounting bolts to break. Call any alternator overhaul shop and they will not be able to look up parts for a military model alternator. But I removed mine from the LMTV and took it to the auto electric place in town and it took them 4 minutes to find a bushing that fit and install it, $10. I also bought a grade 8 pivot bolt at the hardware store to mount it. Hopefully this case is closed.

 

[rosco]

You did it right! Welcome aboard too. I have been fooling with these MV's 40+ years, and the parts stores throw up their hands when you say MV. Brakes are much the same, but the heavy truck stores are better about it then the automotive stores. The TM's talk a lot about maintenance, but what the truck receives, is something else. If that alternator was jiggling around, that's what broke the bolt, just from fatigue.