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Spark Plug Torque

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Old Jun 19, 2011 | 07:33 AM
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Default Spark Plug Torque

Need some help here; The correct torque for spark plugs according to the book is between
12\18 foot pounds. My torque wrench starts out at 25 foot pounds so I need to convert 12\18 foot pounds to inch pounds. According to the torque conversion I should multiply foot pounds by 12 in order to get the correct inch pounds so; 12 x 15 (middle of the road between 12 and 18 foot pounds) would be 180 inch pounds. Am I correct???
 
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Old Jun 19, 2011 | 07:37 AM
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Yeah, thats right. 180.
 
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Old Jun 19, 2011 | 07:38 AM
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Correct!
 
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Old Jun 19, 2011 | 07:41 AM
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That's the conversion I've always known, so that is what I would do to, but actually I would just use my wrist torque, but with a real wrench you have it right.
 
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Old Jun 19, 2011 | 07:44 AM
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Boy, that seems like a lot of torque for a spark plug. I usually just hand tighten and then give her a bit of a good snug on my 5/8'" ratchet. I torqued her to 150 inch pounds and it really tightens the plug well beyond what I normally do. Sure don't want to brake off a spark plug.
 
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Old Jun 19, 2011 | 07:45 AM
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Originally Posted by Terrabella
My torque wrench starts out at 25 foot pounds
Do you mean 25 Inch lbs. ?
 
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Old Jun 19, 2011 | 07:49 AM
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Originally Posted by 1flhtk4me
Do you mean 25 Inch lbs. ?
I have two torque wrenches, one is for foot pounds ( which starts out at 25 foot pounds and goes up to 250 foot pounds) and a smaller torque wrench which is for inch pounds. The larger wrench will not go as low as 12 foot pounds therefore the reason for asking for the correct conversion from foot pounds to inch pounds.
 
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Old Jun 19, 2011 | 07:57 AM
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You are right with your calculations. The book calls for 12 to 18 ft pounds. I always use the lower number. I also put some anti sieze on the threads. Where did you find a 5/8 Ratchet???
 

Last edited by Ronp42; Jun 19, 2011 at 07:59 AM.
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Old Jun 19, 2011 | 07:59 AM
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wrist tight plus 1/8 of a turn with a wrench works too.
 
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Old Jun 19, 2011 | 08:06 AM
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Originally Posted by Ronp42
You are right with your calculations. The book calls for 12 to 18 ft pounds. I always use the lower number. I also put some anti sieze on the threads. Where did you find a 5/8 Ratchet???
You don't have a 5/8 ratchet?? I though everyone had one.
I meant to say 5/8 socket! Picky picky!
 
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