Hi everyone,
I have a question, which is more important when changing spark plugs, following the torque setting or the 1/2 to 2/3 turn?
I am changing the spark plugs on our SUV. I bought NGK spark plugs to put in. On the NGK box, it says 1-2 to 2/3 turn. I have a Chilton manual for the SUV, and I looked it up, it says to use 13 lbs/ft to tighten the plugs.
I read on NGK's and Denso website that the use of anti-seize or grease is not recommended because it lubes the threads and when following the correct torque setting, the spark plug can be overtightened.
I did not use any anti-seize on the new plugs, I used the plug socket and extension, threaded it by hand until tight, then used the torque wrench to 13 lbs/ft. It was a little hard to judge because I couldn't turn the wrench in a nice, clean 1/2 turn because of the components around the engine in the way, but I was able to do 1/4 or 1/3 turns of the torque wrench. I tightened to 13 lbs/ft, I did the first two on the driver's side, and was on the third plug. After looking at the threads of the old plug, I started thinking. Yes, I was not putting any anti-seize on the new plugs, but, I had put them on the last set. I started wondering if there was enough anti-seize left in the threads inside of the engine to affect the new plugs.
The NGK website was saying that anti-seize could affect the torque by up to 20%. Reducing the 13 lbs/ft by 20% left me with 10.4, so, I set the torque to 10 lbs/ft, and tightened down the third new plug.
Wondering about the other two I had just done, I went back, loosened them back up, tighten by hand, then torqued them to 10 lbs/ft.
The reason I asking about what to follow, the torque setting or the 1/2 to 2/3 turn, is because of the second plug.
The first plug I loosened back up and retightened seemed fine. With the 10 lbs/ft setting, it tightened roughly about 1/2 turn.
The second plug I loosened, tighten by hand, but, using the torque wrench, it only went about 1/4 turn before it was clicking. Loosened it back up, and did it again, same thing.
Why is it only going about 1/4 turn before it clicks? When the other two were roughly 1/2 turn?
Something going on with the plug? Or threads in the engine?
Now I am concerned about the second plug, I don't want it to be under tightened, but, I don't want to over tighten it either.
I read the cleanliness of the threads can also affect the torque setting, makes sense, any kind of crud or build up would cause more resistance to turn, possibly reaching the amount of torque, causing the wrench to trip, before the plug was fully tightened. Judging by the way I could thread it by hand, the threads seem pretty clean, I think.
So, what do I follow? Torque setting? 1/2 to 2/3 turn?
Thanks,
I have a question, which is more important when changing spark plugs, following the torque setting or the 1/2 to 2/3 turn?
I am changing the spark plugs on our SUV. I bought NGK spark plugs to put in. On the NGK box, it says 1-2 to 2/3 turn. I have a Chilton manual for the SUV, and I looked it up, it says to use 13 lbs/ft to tighten the plugs.
I read on NGK's and Denso website that the use of anti-seize or grease is not recommended because it lubes the threads and when following the correct torque setting, the spark plug can be overtightened.
I did not use any anti-seize on the new plugs, I used the plug socket and extension, threaded it by hand until tight, then used the torque wrench to 13 lbs/ft. It was a little hard to judge because I couldn't turn the wrench in a nice, clean 1/2 turn because of the components around the engine in the way, but I was able to do 1/4 or 1/3 turns of the torque wrench. I tightened to 13 lbs/ft, I did the first two on the driver's side, and was on the third plug. After looking at the threads of the old plug, I started thinking. Yes, I was not putting any anti-seize on the new plugs, but, I had put them on the last set. I started wondering if there was enough anti-seize left in the threads inside of the engine to affect the new plugs.
The NGK website was saying that anti-seize could affect the torque by up to 20%. Reducing the 13 lbs/ft by 20% left me with 10.4, so, I set the torque to 10 lbs/ft, and tightened down the third new plug.
Wondering about the other two I had just done, I went back, loosened them back up, tighten by hand, then torqued them to 10 lbs/ft.
The reason I asking about what to follow, the torque setting or the 1/2 to 2/3 turn, is because of the second plug.
The first plug I loosened back up and retightened seemed fine. With the 10 lbs/ft setting, it tightened roughly about 1/2 turn.
The second plug I loosened, tighten by hand, but, using the torque wrench, it only went about 1/4 turn before it was clicking. Loosened it back up, and did it again, same thing.
Why is it only going about 1/4 turn before it clicks? When the other two were roughly 1/2 turn?
Something going on with the plug? Or threads in the engine?
Now I am concerned about the second plug, I don't want it to be under tightened, but, I don't want to over tighten it either.
I read the cleanliness of the threads can also affect the torque setting, makes sense, any kind of crud or build up would cause more resistance to turn, possibly reaching the amount of torque, causing the wrench to trip, before the plug was fully tightened. Judging by the way I could thread it by hand, the threads seem pretty clean, I think.
So, what do I follow? Torque setting? 1/2 to 2/3 turn?
Thanks,
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