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Tach Drive Assembly

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nwetzler

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Hi All...hopefully this post reaches you Cub maintenance experts out there who have probably run into this problem a million times...I could sure use your help!

As this is my first post, I apologize in advance if it's in the wrong place, or has been answered one or more times. I own a 47 J-3 with the original A65-8. My grandfather (the Cub's owner since it's purchase from the CAP in 1950) and I recently attempted to replace the oil seal found inside the tach drive assembly, as it had been leaking, both from the knurled end that attaches to the assembly case, and the connection at the back of the instrument panel. After picking up the seal, speaking with our long-time mechanic, and grabbing my soft-jawed pliers, 7/8 box wrench, and safety wire tool I set out to replace the seal, which by all accounts was supposed to be an "easy" job. Of course, nothing is ever easy, and now I'm in quite a predicament. When trying to remove the piece that the knurled end attaches to (which then attaches to the accessory case) I, and 2 others who were helping, couldn't get the bolt to budge. It's a small amount of surface area to work with, and the box wrench just wasn't cutting it. After a brief call to the mechanic to ensure that the piece was right-hand (or positive) threaded, which he absolutely insisted it was, we continued on, this time with a deep-well 7/8 socket. Needless to say, there is not a whole lot of room to work on this job without removing the exhaust, or mags, or both...so we ended up taking a box wrench and hooking it onto the ratchet in order to gain leverage. A few unsuccessful tries later, and we were considering our options for heating the bolt, assuming there could be lock-tite on the threads, when voila! the bolt started to budge. My joy turned to horror when, as the second turn of the wrench made its way around, I did not feel the easily recognizable feeling of a bolt de-threading, but rather, the unmistakable slip of a bolt that was breaking off. Now, I have what I'm sure most of you reading this are aware is a nightmare scenario. I have an aluminum bolt that has been sheared off, stuck in my assembly case, and just to clarify...there is absolutely nothing to grasp onto. The bolt broke at the first thread, and has left little (to my knowledge) options for what to do next. The next day, the mechanic met me at the hangar, and after examining the situation, said I will need to remove the exhaust in order to see if there's enough room for him to punch or saw the bolt out. If that doesn't work, he said the next step is to remove the entire motor, and try to punch/saw the bolt out again....and if that doesn't work, replace the entire accessory case. So here's where I need you crafty, Cub savvy experts to throw me a bone. Has anyone had any similar situation to what I'm dealing with, and if so did you have any success getting the bolt out? If not, I'm also open to pure suggestions at this point to. I just want my cub back!!!!! The tach drive is still inside the bolt, so from my perspective unless that can be removed, tapping the bolt with progressively larger pieces is out, as there is nowhere to tap the piece to begin with. I think that about sums up the issue, although if I left something out, please let me know and I will gladly provide any info that might help someone help me! Many thanks in advance!
 

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