Today i decided to change the sparkplugs on my 3ln, not a tough job i wouldnt have thought... i changed the first plug without much trouble, and then i got the second one out, i went to put the new plug in and the trouble started. The new plug was very tight to go in so after a few turns i backed it off and started again as i thought that the thread might be crossing. The second attempt started a bit better but as i got the plug down a bit it started going tight it was still no where near where it should have been then it snapped off as i was turining it! So now what do i do? Anyone ever heard of this happening before? Any advice on what to do from here would be appreciated. I started taking the bike apart because obvilously the heads going to have to come off. <!-- s --><img src="{SMILIES_PATH}/icon_sad.gif" alt="" title="Sad" /><!-- s --> [/b]
the thread must have already been crossed if you're lucky and you do it carefully you might be able to clean up the threds without taking the head off go out and buy a 10mm x 1mm pitch tap (thread cutter) you will need to get a fluted type i will post a picture of the one i have, so you'll know what i'm talking about BTW they're hard to get and a bit pricy
CAUTION! Grease up your tap before chasing the threads!!! tap down a few mm then pull it back out and take the chips out of the grease. Regrease and proceed a few more mm. Repeat this until you are all the way through. It is important to not let any chips find there way into the cylinder. They can become imbedded in the dome of the cylinder head and lead to pre-ignition when they basically turn into glow plugs.
