Stripped Spark Plug Hole

[Anonymous]

I recently picked up a spare GS850 that I would like to try and get running. Come to find out it has a stripped spark plug hole (number 4). Does anybody have an idea on a fix for this type of problem?

Thanks
Curt

[Billy Ricks]

Heli coil or Timesert it.

[saaz]

If the hole is more cross thresed try a spark plug chaser. This will clean up the thread. If it is worse, I have seen plug repair kits that are supposed non-tap ones, but I think they do slightly enlarge the hole and then an insert goes in.

[Billy Ricks]

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2580897871&category=25262

[Anonymous]

Are helicoils easy to use? How does it know what size spark plug you are using? Does the head have come off for this to work?

[saaz]

The sava a thread is waht I have seen. The spark plug chaser just needs to be run though. I had a cross threaded plug that was restored very nicely.

[nabrams]

I once stripped the threads of the spark plug hole for my 1977 Honda XL350. I was really worried that it would be hell to repair.
I worried for nothing - it was easy to fix.
I got the spark plug hole repair kit from heli-coil (make sure you get the right one), and now the bike runs even better than it did before (I guess it's got better compression now). I didn't have to remove the head or do any drilling. Use grease on the tapping tool.
The trick is to tap a couple of threads at a time, back the tap out, clean the chips off the tool, re-grease and then repeat this as many times as necessary. I don't think much of the chips (if any at all) fell into the head. The grease catches it all up pretty well if you frequently re-grease the tapping tool.

[mcconnell]

If you try the inserts where you have to tap in new threads, follow the 'greasing' advice carefully. DO NOT use a vacuum cleaner to get out suspected chips without removing the carbs from the bike. If the intake valve is open while you are vacuuming, the carburator for that cylinder will gladly deliver a fuel-air mix into the cylinder. And vacuum cleaner. Disaster far beyond a stripped thread could result.

[lhanscom]

If you try the inserts where you have to tap in new threads, follow the 'greasing' advice carefully. DO NOT use a vacuum cleaner to get out suspected chips without removing the carbs from the bike. If the intake valve is open while you are vacuuming, the carburator for that cylinder will gladly deliver a fuel-air mix into the cylinder. And vacuum cleaner. Disaster far beyond a stripped thread could result.

Good tip, I wouldn't have thought of that! 8O

[Anonymous]

Best to take the head off, no questions asked. Grease on the tap helps, but there is no certainty that chips will not get in the cylinder. If it is a brand new engine on a really nice bike, I wouldn't dare take the chance of working with the head on. If this is a $200 project bike and you have really nothing to lose, who cares.

[Anonymous]

Helicoil part# 5334-14, can be done with the head on. Use grease to catch the chips, I did it in the summer on my GS 1000, worked great. Good luck.