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Discussion Starter #1
I had a spark plug blow out on me the other day, I pulled out the plug and tried to thread in a new one but the threads are gone on the head. I can add a new coil (tap it out and add new threads) but I am wondering what everyone here thinks about that.

One one hand I would have to find a kit with a long enough tap to get down in the spark plug well or I can take off the head and that would make sure the cylinder is clean from any shavings.

I feel like taking off the head is a motor out job and will take a lot more time but would also make the fix last longer.
Any info is helpful.
Thanks.
 

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I think that I would go with a new head, as if it has happened with one plug, it could happen to the others.
 

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Remove the head and helicoil the threads. You will not be able to install a helicoil or timesert with the head in place.
Plug blew out because it was not properly tight in the head. Check your other plugs.
You can pull the head without completely removing the engine, but you will need to pivot the frame back to gain good access.
 
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Discussion Starter #4
I have bought replacements plugs and yelled at my mechanic (me). The plug shot the ignition coil out and broke that too. so I will go with the head pull.

When do you mean by "pivot the frame"?

Thanks @esq'z me for that.
 

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If you do a little searching you should find examples of pivoting the frame up. Engine supported underneath and rear wheel in the stand. Saves you complete disassembly and disconnecting everything.
 

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Ha, I just had this happen and put in a Time-sert last weekend! I assembled or made all of the needed tools for far less than the Time-sert price as well. If you were further south I would have been happy to lend to a hand.
479762
479763
 

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I figured that pivot the frame was what is in @pittmeister photo. How did you clean out all the shavings?
I used heavy grease on the drill and tap to catch as many chips as I could during the process. Afterward, I used WD-40 to "wash" the cylinder and a vacuum pump to suck it back out. Last, lots of compressed air and little bit of carb cleaner to get rid of any residue on the spark plug threads.

I read up some more about it after the fact and saw suggestions about stuffing a greased rag or rope into the cylinder which seems like a more comprehensive approach so long as you can get them out. I even considered stuffing one of those little cocktail umbrellas down there to catch chips.
 

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Is blowing plugs out of the head a common problem?
This is an interesting thread.
 

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Is blowing plugs out of the head a common problem?
This is an interesting thread.
Common on lots of engines including cars..... like Mitch said, IF left loose.
 
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Discussion Starter #13
The other 3 were still tight but I have a fear of over torquing plugs on aluminum heads. Now I know it can be too loose or too tight :(
 

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Use a torque wrench. That's what they are for.
 
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