Serial number 1E081216 I know the manual says 20 newton meters but I removed the plugs yesterday and found a little bit of oil on the plugs. Took a flashlight and looked into the holes in the camshaft cover where the plugs go and found a little oil in each of the 8. This engine was overfilled with oil when I got it and ran that way for 11 hours before I corrected it. Has 28 hours now. In the past I've always torqued plugs to 20 ft lbs. Think it would be ok to torque to 20 ft lbs?
20Nm is roughly 15ft lbs
Found another place in the service manual that said to torque to 22 nm
My manual shows 20NM or 177 in pounds. I would not over torque them, the threaded diameter is small for a spark plug (12m x 1.25) and hence more apt to pull the threads. I would use a 1/4" drive inch pound torque wrench because a 3/8" or 1/2" are at the very bottom of their range and can easily exceed the torque it says it is applying. With new plugs if you can feel the gasket seat and half to turn more than 3/4 of a turn to reach torque you may be over torquing the plugs.
Last edited by howieranger; 08-09-2020 at 02:02 PM.
2018 Z521L 250 PRO XS V8
I believe the camshaft cover seals may be leaking causing the oil I found on the sparkplugs?
That would be something you would need to get your dealer to inspect and determine. LOOSE spark plugs (not torqued adequately) can cause leakage, of course.Originally Posted by C.Warrix
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