spark plug failure

666damned · Post by **666damned** » Fri Apr 03, 2009 10:51 pm

the last time i saw a plug like that(first pic) Charles..........i also had a hole in the piston crown of an X7........

dirk · Post by **dirk** » Sat Apr 04, 2009 9:21 am

Hi Charles

stop your maintenance repairs now!

i am the man with the every day engine trouble

the plug.....
to short helicoil...you have between the plug and the plug thread a big gap.
i think the plug can not dissipate adequate the heat to the cylinder head and overheat.

cheers
dirk

Charles · Post by **Charles** » Sat Apr 11, 2009 10:21 am

So I took the engine out of the bike and the barrels plus head off the bottom end: piston is damaged and so is the lining of the barrel

the-elf · Post by **the-elf** » Sat Apr 11, 2009 1:38 pm

I would get the barrel replated and a new piston fitted along with a decent head. Oh and send the boys round to deal with the pr*t who fitted the insert in the first place.

Charles · Post by **Charles** » Sat Apr 11, 2009 1:53 pm

the-elf wrote:I would get the barrel replated and a new piston fitted along with a decent head. Oh and send the boys round to deal with the pr*t who fitted the insert in the first place.

Yes, will fit the newly plated barrels I bought from Lee plus a set of new pistons. Now I have to fit one new barrel/piston, I'd rather do both sides, as I don't know their history. Bought the bike with no knowledge of its history whatsoever.
Luckily I got a spare head as well. Only things I haven't got are a set of base gaskets. Dirk send me a scan of them, willtry to make them up myself. Now I need to find someone who can fix the old head, as I don't want to bin it.

Will have to deal with the d..k who fitted the helicoil myself, no boys around

Charles

the-elf · Post by **the-elf** » Sun Apr 12, 2009 10:24 am

Make sure that there is no bits of metal etc. floating around the crankcase. When this happened to be (air leak) I stripped and cleaned the crank and cases and was amazed at the amount of crap that was in there. Also if you wash the crank with solvent etc. remember to re-soak the bearings in two smoke oil prior to assembly.

Base gaskets are still available from big K. I ordered a couple of sets only a month or two ago from Z-Power.