03 450 cylinder head reassembly question

3 replies to this topic

Posted June 21, 2008 - 11:01 PM


When putting the head back on the cylinder the manual says to clean the bolts, washers and bolt holes, apply moly grease, torque bolts to 22 ft lbs, remove bolts, reapply grease and retorque to 14 ft lbs. My question is won't this screw up the head gasket by tightening, loosening and retightening. I thought they were made to be tightened once and not reused? I don't recall on any other bike I have owned where you follow this procedure. I have the engine back together and it runs fine but seems to be getting hotter than usual. Leaking head gasket perhaps? Thanks for any ideas you might have!

  • grayracer513

Posted June 22, 2008 - 06:39 AM


That's not all it says, is it? :thumbsup:

The process is to pre-crush the gasket by torquing to 22 ft/lb. After that, torque is relaxed, and the bolts run down to 14 ft/lb to establish a base torque. From this point, the bolts are rotated 1/2 turn farther, in 1/4 turn increments. This results in a more reliably even clamping force on the head than can be achieved by just measuring 27-30 ft/lb of torque.

And no, the gasket is not damaged. It is crushed farther when torqued the second time than the first, so it's OK.

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Posted June 22, 2008 - 07:55 AM


You're right, I left out the 1/2 turn part. Thats what happens when I post at 1 am after working on the bike all day. However I only tightened them another 135 degrees because I had reached 40 ft lbs of torque at that point and worried about stripping or breaking something. Would that be enough?

  • grayracer513

Posted June 22, 2008 - 11:50 AM


If you did the pre-torquing step correctly, and started at 14 ft/lb, torque them the full 180.

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