Scooter Doc
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Post by Kaveman on Mar 16, 2011 19:38:17 GMT -6
Needed asap: torque specs for head assembly nuts ! ( to tighten 4 nuts atop the valve rocker arm assy ) 157qmj engine
Bill C.
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Scooter Doc
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Post by sprocket on Mar 17, 2011 17:55:20 GMT -6
Torque the nuts down to 13-15 foot pounds.
Be sure to tighten the nuts down in two steps using a crisscross pattern. Be sure to lubricate the rocker arms before assembly.
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Clinician
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Post by jaybenedetto on Jun 22, 2014 23:08:51 GMT -6
some on torqued my head nuts to 25ft lbs. i drove it across town maybe 20 min tops. can i back them off and reset them to 15 and would it be safe? was there any real damage? thanks  |
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Doc's Anything Goes
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Post by tvnacman on Jun 23, 2014 3:57:14 GMT -6
Yes loosen them up and retorque them .
John
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Post by royldoc on Jun 23, 2014 12:14:02 GMT -6
some on torqued my head nuts to 25ft lbs. i drove it across town maybe 20 min tops. can i back them off and reset them to 15 and would it be safe? was there any real damage? thanks I accidentally set my torque wrench to 25 instead of 15 once. The corner of the rocker arm assembly snapped off and damaged the threads in the nut.   I would look for any cracks.Also it may have deformed the bracket. Roy |
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Clinician
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Post by jaybenedetto on Jun 23, 2014 14:12:49 GMT -6
so u think from just a cruse across town screw it up warped it or broke it?
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Post by Bashan on Jun 23, 2014 15:31:54 GMT -6
No man, you're cool. If you don't see any damage on the cam retainer don't worry about it. Those dowels are strong as can be and you won't hurt the head or cylinder. The way I do those four bolts is set them to 17.....ride it a few times, then retorgue. The metal can stretch a little and they're often a little under 17 second time around. My point is, metal has a little give, so if the cam bracket is good, retorgue and ride...you didn't hurt anything. Rich
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Post by royldoc on Jun 24, 2014 11:42:02 GMT -6
I agree,it's probably ok. Just re-torque the nuts and do a visual. Mine broke just before I got to 25lb on the last nut. Also it would be a good idea to check the valve gap after you re torque the nuts. It probably won't change, but ya already got the valve cover off and might as well.
Roy
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