Its really not that bad, you can it all with a decent socket set (<$100) and some time, which you have since you can take the train
![Smile :)](./images/smilies/icon_smile.gif)
Lots of people on here to help if you run into trouble
But get your diagnosis down before you rip it apart
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I can tear it down again ofcourse, but I wished i checked if my engine had the old design friction gear last time..............1. Pre-ignition: this is usually caused by an excess of carbon build up in the combustion chamber, which gets very hot and ignites the mixture before the plug fires. The knock comes from the force of the early ignition pushing the piston and rod back down against normal rotation (because the piston isn't in the intended ignition position yet) and it bangs against the bearing essentially destrying it in very short order. Pretty bad.