SPARK PLUGS DIFFERENT SIZES?

[kevsem65]

I went to change my plugs for the first time since I bought the car yesterday with a set of new ngks, when I got to #3 the plug is a different size?? its wider and the ones in the box are all the same size I didn't bother pulling #4 bc I didn't have plugs to replace them but is that right they are not all the same size?

[aj81spider]

That's not right. They are all supposed to be the same size.

[kevsem65]

hmmm I thought so , why and how would it be different?

[azruss]

The PO probably stripped the threads, so just tapped a bigger hole and matched a plug to it. Seen a lot of funky stuff with plug threads, but this is a first

[kevsem65]

great... I was hoping someone was gonna say, "oh yeah, theyre different sizes".

[bradartigue]

Look at the bright side, you'll never have to worry about rebuilding that head. Straight to the trash (keep your cam boxes). Next time you do a head gasket buy a new base head, save yourself the misery of trying to weld that up.

In the meantime enjoy the weird.

[kevsem65]

Actually pep boys had a spark plug repair kit that worked perfectly. funny thing the guy behind the counter knew exactly what I was talking about and gave me a very reasonable fix. The kit had 3 different sized sleeves and a tap to install them and a tool to seat it. The install went smoother than I could have hoped for and I put new ngk platinum plugs in. The only reason I should ever have to replace them is putting on a performance head.

[aevansgatech]

Well, let's make it occurrence #2. I have a larger spark plug size in cylinder #2

Went to replace all of them and just the one was oversized. It was retapped so I'll get a new plug in that size to match the other new plugs.