Harmonic balancer bolt

[Blazin]

Driving down the road yesterday afternoon, almost done plowing. I hear ting  ting   ting ta ting ta ting  ting, what in the heck  ?
I get out, look, the harmonic balancer bolt is sticking out and the fan is tinging it! I pull it out, its broke off  ! Drive it to the shop. pull the belts, fan, fan shroud. Up on the lift, pull the pulley, and balancer. Drill, and easy out it. Piece I got out was about 1/2 long. Put it all back together with a NOS alt belt as the one I took off had a 2" long split length wise. Never seen a serpentine belt split like that.

[thirsty]

You got lucky with that! It could have gone a lot worse for you. Do you have any idea why it broke off that far in?

I had a similar problem years ago. Just bought a truck and it had a lot of lifter noise. A week or so before I had to make a 3 hour all highway trip with it I thought I better look into the lifters. Pulled the valve covers and none of the lifters were pumping oil. I got a cam and lifter set and some new push rods and a timing set. When I took it apart and installed the parts everything went like normal. Putting the balancer bolt back in it kept turning with an 8" ratchet. When I realized what was happening I was furious! I think that was the only time I have ever thrown a tool in the garage. The bolt was fine but the threads in the crank weren't. After I calmed down some I went to talk to my old school mechanic dad. We looked at it and decided we could thread it more. It worked out and I cut a new bolt that would grab the few new threads and used loctite. I drove that motor for about 4 years afterwards.

[Blazin]

Well this morning, I here ting ting ta ting ting ting... again! Bolt broke again. This time its getting a new used balancer, new key, the hole tapped to 1/2x20 thread, and a new bolt. Posibly a new used bottom pully if I can dig one out of my box trailers! 

[Captkaos]

Dude that would worry me doing it twice?  Is the tension too tight?

[Blazin]

Its been fine since, the key, and key way had some play. The balancer was moving around even when the bolt was tight.