help!!!!!! stripped hex bolt on crankcase!!!!!!!!

30 replies to this topic
  • Digger01

Posted September 10, 2009 - 06:48 AM


Thats because he coached me through this not to long ago.

Two of my bolts sheared when assembling, right at the hollow protion and I had to take the cover off twice.

I would order some new bolts so if one breaks upon assembly you will have them if needed. I feel they were stressed from time.

  • bakeyz426f

Posted September 10, 2009 - 08:32 AM


this bolt doesnt look like the part without treads is very big in the manual. it looks like it could have threads in bouth case halves.
it is part number three its shows the bolt hole but it doesnt show the actual bolt on the parts picture. it does in the manual. i was going to drill but the small smooth part got me a little scared to do it. if i drill the head off can i still use an extractor if that doesnt work? does that bolt only go through one case half?

  • grayracer513

Posted September 10, 2009 - 10:08 AM


This is the last time:

NONE of those bolts thread through both halves of the case. If they did, the could not clamp the two halves together. They pass through the left case and thread into the right, just like all the rest of them that you removed. Drill the head off and be done with it.

  • bakeyz426f

Posted September 10, 2009 - 12:06 PM


i got it. drilled it out and it unscrewed thanx

  • squid john

Posted September 10, 2009 - 12:10 PM


it takes that much to get out a screw

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  • bakeyz426f

Posted September 10, 2009 - 12:37 PM


do i need to remove the neutral switch before i split the cases. also do i need to remove the oil pump before splitting cases.

  • grayracer513

Posted September 10, 2009 - 01:08 PM


do i need to remove the neutral switch before i split the cases. also do i need to remove the oil pump before splitting cases.

No, but in both cases, I would. There's a small pin and spring you could easily loose track of in the neutral switch.

  • USED YZ426F

Posted September 10, 2009 - 04:06 PM


The problem here is that the head of the bolt is stripped, if I read this right, not the threads. An old standard trick is to drill the head off the bolt by running a quarter inch or larger drill down on it until the head pops off. The bolt can be easily removed with pliers once the cases are opened up.


Been there and done that (more times than I want to admit).

  • bakeyz426f

Posted September 10, 2009 - 05:11 PM


i left it on and i didnt see any springs come out so hopfuly its in still together. i hate the philips head screws they put on the neutral switch. easy to strip out. after i had it apart i decided to start taking the nuetral switch off because the trans wasnt comming out. i strip a philips head but got it out by hack sawing and using a standard srewdriver.

  • rufusz

Posted September 11, 2009 - 12:27 AM


Trick with Philips head screws is to always use the proper size and proper quality screwdriver. Do not over tighten the screw and when unscrewing, apply enough pressure so the screwdriver doesn't jump/move (thus the need for proper size and quality) in the head. Most screws get destroyed because people use old/small/worn screwdrivers on them.

  • davcon

Posted September 11, 2009 - 05:42 AM


I've always used an impact driver for loosening phillips screws on cases (the one where you smack the back with a hammer and twist simultaneously). Used to be a standard item. That tool has been rolling around in my tool box since the Hodaka days!

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