Spark plug maintenance

[nissanh]

Hello all,

These days I am helping my cousin who has a 1999 pathfinder to extract a stuck spark plug.

Who ever did the spark plugs didn't put any anti-seize on the threads and as a result he broke the no:02 spark plug while trying to remove it. He tried using the easy-out tool and no luck so far. He is now working on the time-sert kit. If this fails, he needs a cylinder head!

We tend not to touch the conventional plugs until about 20K-30K miles, and with this many miles carbon deposits may fuse the spark plug to the cylinder head. Case is worst with platinum plugs where we don't replace them until about 50K miles.

Just make sure to put anti seize lube before you install the spark plugs.

 

[yota_addict]

I'm no expert on any of this stuff but sounds like the spark plug is out if he's using time sert. Seems if a spark plug gets stuck maybe penetrating oil would help. Let it soak in for a day or so. Breaker bar? I've actually had a stuck emissions control valve that was the size of spark plug removed easily with an impact wrench, unfortunately you take a chance with that and possible destruction of the threads leaving you to do time sert or new head.

 

[TheDurk]

Hello all,

These days I am helping my cousin who has a 1999 pathfinder to extract a stuck spark plug.

Who ever did the spark plugs didn't put any anti-seize on the threads and as a result he broke the no:02 spark plug while trying to remove it. He tried using the easy-out tool and no luck so far. He is now working on the time-sert kit. If this fails, he needs a cylinder head!

We tend not to touch the conventional plugs until about 20K-30K miles, and with this many miles carbon deposits may fuse the spark plug to the cylinder head. Case is worst with platinum plugs where we don't replace them until about 50K miles.

Just make sure to put anti seize lube before you install the spark plugs.

NGK says quite clearly their 'tri-valent' plated plugs don't need anti-seize. (see attachment) I have been using NGK plugs without anti-seize every 30k since Day 1 (well, since 30k, 175k now) and I never have a problem. Odds are either yours were not plated plugs or they were wildly over-torqued or left in long after specified mileage life. Using anti-seize can actually CAUSE over-torquing of spark plugs.

Denso also recommends against. http://www.globaldenso.com/en/products/aftermarket/plug/basic_knowledge/installation/index.html

I am a big fan of anti-seize but not on plugs and not on lugs. Use NGK or Denso, torque to spec, change on time and you will be just fine with no anti-seize.