shifted to second, thats all she wrote.

6 replies to this topic
  • worleybird81

Posted June 01, 2014 - 05:15 PM


Just rebuilt my 06 450. Intake valves were shot, so replaced those and figured since had it apart that I would throw in a new piston. My first time on a four stroke rebuild. I had the shop do my valve work and I was meticulous about every thing I did. Thought I had it until I shifted to second, and bang just quit. Anybody have any ideas?

  • Slow and Jerky

Posted June 02, 2014 - 04:08 AM


Does it kick over or did it seize?

  • dadat40

Posted June 02, 2014 - 01:18 PM


Take it apart and see where you went wrong

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  • worleybird81

Posted June 02, 2014 - 04:57 PM


Kicks over, pulled valve cover and my intake is off 90 degrees

  • grayracer513

Posted June 03, 2014 - 08:08 AM


Check the cam and caps for signs that it seized.  It is not difficult to deform a cam cap by seating them forcibly, torquing them excessively or out of sequence, that sort of thing.  The cam chain was replaced when you did the build, no?

  • worleybird81

Posted June 03, 2014 - 05:51 PM


Thanks Gray racer513. Did not replace the cam chain, and my torq and sequence was by th book. Signs that cam has seized???

  • grayracer513

Posted June 04, 2014 - 06:44 AM


 Signs that cam has seized???


Yes.  If the bearing surface under the cap is galled/scored badly, your cam may have seized.  But it's also possible that the chain has a tight link or two that caused it to slide and throw your timing off that way.  Either way, it should not be trusted after a timing slip.  Replace it, and the tensioner, too.

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