Spark Plug Installation - Torque Specs

SuperCuts

Forum Newbie
Hello Everyone,

Probably a stupid question but I will post it anyway...
I changed the plugs in my John Deere Walkbehind (61 inch with Kawasaki Engine). I removed the original plugs (from the factory) using my digital torque wrench. It took 14.2 Nm of torque to loosen them.

The JD maintenance book calls for the plugs to be torqued to 27 Nm. As I installed the new plugs, I used the good digital torque wrench using the old fashion get the plug tight and turn 1/4 more. Using this method, I noted the torque on the wrench was around 15 Nm (no were near the 27 Nm called for in the book).

Since the old fashion way got me close to the torque that was required to break the plugs free, I am really concerned with trying to get to 27 Nm...It seems like they would be way over torqued....

I have changed a lot of plugs over the years. I have never seen this kind of discrepancy. Should the break away torque and the tightening torque be similar in this case (since the original plugs are from the factory)? Since the plugs are tight and it runs fine, does anyone think I should try to get to the 27 Nm?

Kinda of stupid I know...again, my only concern is the great discrepancy between the factory spec and where I felt comfortable. . .

Thanks for any thoughts.
 
The calculator generation who only understand numbers in place of what the numbers actually mean can not fart without a number for it.
Finger tight + 1/4 turn if fine .We know that all that is required is some crush on the sealing washer
 
With sealing ring per NGK. Taper seat has a different spec.

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Now of course this for new plugs, older used plugs it is as Bert suggests as the sealing washer is already crushed.
 
Last edited:
27Nm is high for a plug with a crush washer. That is more like a taper seat plug in an iron head. I am with bert. 1/4 turn after finger tight.
 
Hello Everyone,

Probably a stupid question but I will post it anyway...
I changed the plugs in my John Deere Walkbehind (61 inch with Kawasaki Engine). I removed the original plugs (from the factory) using my digital torque wrench. It took 14.2 Nm of torque to loosen them.

The JD maintenance book calls for the plugs to be torqued to 27 Nm. As I installed the new plugs, I used the good digital torque wrench using the old fashion get the plug tight and turn 1/4 more. Using this method, I noted the torque on the wrench was around 15 Nm (no were near the 27 Nm called for in the book).

Since the old fashion way got me close to the torque that was required to break the plugs free, I am really concerned with trying to get to 27 Nm...It seems like they would be way over torqued....

I have changed a lot of plugs over the years. I have never seen this kind of discrepancy. Should the break away torque and the tightening torque be similar in this case (since the original plugs are from the factory)? Since the plugs are tight and it runs fine, does anyone think I should try to get to the 27 Nm?

Kinda of stupid I know...again, my only concern is the great discrepancy between the factory spec and where I felt comfortable. . .

Thanks for any thoughts.
Seat by hand and 1/4 turn for new, 1/8 turn for used.
 
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