For those without much experience at taping a hole, I will add this. Make sure you have a sharp tap. Do not use an old dull beat up one you found in the bottom of the drawer. Get everything you can out of the threaded hole using compressed air. A nozzle long enough to reach the bottom of the hole is best. Use a light oil on the tap. Turn tap at slow steady speed. I if very little resistance is felt, turn tap all the way to bottom of hole. Stop turning immediately when bottom of hole is reached. Back tap out, blow off with air, blow hole out with air until nothing is coming out of hole. If resistance is felt while tapping, go a little way in, remove tap from hole. Blow hole out with air, blow tap clean and re oil. Do this as many times as necessary until bottom of hole is reached. This may or may not be quite time consuming depending on the amount of crud in the threads. PAY ATTENTION: DO NOT GET IN A HURRY!!! Taps are very hard which means they are brittle!!! They have to be hard to cut steel. If you break one off in your engine, its NIGHT MARE CITY!!! Because of the hardness of the tap, they can be EXTREMELY difficult to remove when broken. Remember, cleanliness, light oil, do not force it. Accurate torque is achieved with a clean, lightly oiled thread.