Need Help! Stripped Mulching Tooth bolt

yellowdogsvc · Apr 10, 2009

I have a Cat HM312 mulcher, almost identical to the FAE 125 fixed tooth mulcher head.

There are two bolts that hold the teeth on. I got down to my last two teeth and stripped out two of the bolts trying to get them out. The allen head socket won't work anymore. I have been grinding on one for about 4 hours trying to get the head grinded down far enough so that the tooth falls out but it is a S L O W process on a grade 8 bolt using a small, air powered die grinder. It's all that will fit. I tried my acetylene torch but was weary of applying too much heat and tempering the tooth pocket. Does anyone have a better solution? These bolts were evidently seized with loctite when the head was built. I only have two teeth left but again, I don't feel confident using the acetylene torch though I imagine a good welder could do it. Thoughts?
Thanks! Yellow Dog

Eagleview · Apr 10, 2009

If they were in fact put in with Loctite , you will need heat anyway to break the bond . You will never get the bolt shank out , without a head and locked with Loctite . When cutting something like that with a torch , it is best to put a dab of weld on the object . Start your cut on the dob of weld and carry on through the object . The dob of weld heats more quickly than it would normaly take to heat the object . As kids , we would lower our cars by cutting a coil or two from the springs . As it would take maybe 30 seconds to heat the round coil wire and would destroy the temper , we would put a dob of weld on the spot and we could then quickly cut the coil from there .

If it were me , i would weld a nut onto the stripped bolt head and undo it while the weld is still warm .

sal64 · Apr 11, 2009

hello did u try to drill out head allen head bolts are hard but with the right drill sharpend right you can do it,ive done it many times.

SPYDERLK · Apr 11, 2009

With stripped Allen heads I have good luck with grinding down the next larger size on a taper and then driving it into the stripped socket.
larry

yellowdogsvc · Apr 11, 2009

I ended up grinding down to the threads then I hammered the threads and the tooth popped off. I then used a pick through the bottom to knock any of the metal that was left in the tooth holder. It took about 4 hours to grind. I probably need a more powerful die grinder and/or a harder stone but that seemed to work. I now know what will work without changing the temper on the tooth holder. Good thing, because I stripped the other bolt on the very last tooth. I figure it wasn't too bad getting 26 of 28 teeth off without a problem. I now have 27 new teeth and one used one. Wasn't in the mood to grind any more.

I like the idea of cutting the bolt out but I was afraid of damaging the tooth holder and creating a balance issue or make it prone to breaking.
Thanks for the responses.. Yellow Dog

Eagleview · Apr 11, 2009

Sorry , i thought the bolts were threaded into the adaptor , they obviously had nuts behind them .

yellowdogsvc · Apr 12, 2009

Iron Horse said:
Sorry , i thought the bolts were threaded into the adaptor , they obviously had nuts behind them .

The bolts got through the tooth holder into the tooth which has the threads. No nuts visible. I tried cutting into the tooth but was afraid I was tempering the tooth holder too much so I backed off on the heat. I hope I didn't weaken that tooth holder already.

Mowermoney · Apr 12, 2009

Yellowdog:

This happens every time I change a set of teeth on my FAE's. Don't woory about overheating the tooth holder. Just cut with the torch straight in and awat form the tooth holder and ct through to the bolts, one at a time. Shouldn't take over 5 minutes. I had to cut several off last time I changed a set.

Over time the bolts seize and no matter how hard you try, you can't loosen them. I tried heating the teeth with a rosebud and using an oversize allen socket and still couldn't budge them.

Just cut them off and replace the tooth with new bolts with anti-seize compound applied.

David