Author Topic: Spark plug blow out (Read 3046 times)

wtsheff · « **on:** May 07, 2005, 04:02:13 AM »

Today I blew a spark plug out of the cylinder during hard acceleration.Anyone ever do that B4?

Bazza · « **Reply #1 on:** May 07, 2005, 04:28:51 AM »

I did have a couple come loose from lack of standard Torque wrench proceedures, so technically I could have lost one, but no, caught it in time.

wtsheff · « **Reply #2 on:** May 08, 2005, 02:29:40 AM »

Got a new plug and it will not tighten at all.Evidently the cylinder head threads are stripped-UUgh.Is there any possible way of repairing the threads without the head being removed-labor intensive(I was informed the engine had to be removed)?This will sound stupid but could the threads be tapped with the bike upside down to prevent the metal shavings entering the cylinder?Any other strategies welcome,thanks.

ray nielsen · « **Reply #3 on:** May 08, 2005, 01:44:16 PM »

Check with a automotive machine shop about installing a Heli-Coil insert. Sometimes they can do it with the head in place. They will probably drill out the head with a drill bit with grease in the flutes to trap the metal incurred in drilling, then tap it for the insert, again with grease in the tap flutes.

If the piston is at top dead center they may be able to vacuum out any metal that does get into the cylinder sith a tiny tube attached to a vacuum cleaner an d inserted into the cylinder.

I suspect the best solution is to have the head removed though. If you have to go that far have ALL spark plug holes Heli-Coiled!

Bob Holland · « **Reply #4 on:** May 08, 2005, 02:36:49 PM »

If it were mine, I would pull te head. It is not really that hard, and I would heli coil all 4 while the head is off. The biggest problen with doing it on the bike, as I see it, is getting the drill and tap perfectlly stright. If the machine shop has a way of doing that, then doing it on the bike may be OK.