jeff2wings Posted September 23, 2022 Share Posted September 23, 2022 Plug problem ? THIS is a plug problem 😳........... Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted September 23, 2022 Share Posted September 23, 2022 1 hour ago, jeff2wings said: Plug problem ? THIS is a plug problem 😳........... No that's an unplugged problem 😉 Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted September 23, 2022 Share Posted September 23, 2022 Or the worst example of thread drift yet! 😉 Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted September 24, 2022 Share Posted September 24, 2022 (edited) Like a Helicoil, one was fitted by a 'french' professional, in an OS 120 2 stroke, it came out the same day that the engine was run on unscrewing the plug, rectified by making a brass insert by yours truly. Edited September 24, 2022 by Paul De Tourtoulon 1 Quote Link to comment Share on other sites More sharing options...
jeff2wings Posted September 24, 2022 Share Posted September 24, 2022 Neat repair Paul, how much +did you allow for the interference fit? And that's a nice design/casting by os 😎 no way to repair the head on mine so made a new one Will give it a quick run before adding the fins Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted September 24, 2022 Share Posted September 24, 2022 (edited) 5 hours ago, Paul De Tourtoulon said: Like a Helicoil, one was fitted by a 'french' professional, in an OS 120 2 stroke, it came out the same day that the engine was run on unscrewing the plug, rectified by making a brass insert by yours truly. Sacre bleu ! Helicoils are useless for our plugs and car and motorcycle plugs or any other gas tight fittings. Inserts are the only way to repair plug threads. Once inserted with some thread seal they are often expanded at the bottom end to lock them in place with a special screw. Your French specialist needs some special words in his ear. For heavens sake dont let him near a fourstroke as that would have wasted the head. Edited September 24, 2022 by Engine Doctor Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted September 24, 2022 Share Posted September 24, 2022 I actually threaded the insert and the head, and then screwed it in. Quote Link to comment Share on other sites More sharing options...
jeff2wings Posted September 24, 2022 Share Posted September 24, 2022 Well l hope you used a taper thread or left a shoulder on the insert or you may have the same problem that I had. So I tested the HP61 and all good although it wasn't until I fitted carb No3 that I got it to go LOL ! Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted September 24, 2022 Share Posted September 24, 2022 Chamfer on the inside of the head and a couple of counter punches on the outside to stop it from turning, I can't find the date that I did it but over a year ago and still flying, it was for a club member. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.