WingedFrog
Well Known Member
I changed all Spark Plugs during my annual. Seven out of eight spark plugs went in easily but one wont go. It seems to grab the thread but after about one turn it gets hard and wont turn by hand. I tried to turn it 1/4 to 1/2 turn with the wrench, hoping the resistance would subside but no luck. I got advice to use a tool called M12-1.25 Spark Plug Chaser which delivery I am waiting for now (M12 is not a common size you can find in auto parts stores). The Spark Chaser is not a Tap, it has a tapered thread that will grab the existing thread and should restore the part that is obstructing the path of the plug. I had like to know if anyone had such problem and/or advice on how to proceed with the Spark Plug Chaser. The Spark Plug I retrieved is showing a thread that is intact, i.e., no cross thread sign so I suspect the damage/obstruction is limited to the first threads in the cylinder head's hole. Luckily the hole in question is looking downward which will prevent any debris to fall into the cylinder.