o2 thread size help

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Oct 8, 2004 | 04:59 PM

~~egp320i~~

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From: Central Idaho

o2 thread size help

who knows the exact tread size of an o2 and the thread pitch?
I need to run a tap through to clean up the opening. thanks

Oct 8, 2004 | 05:44 PM

SLAB

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its 18mm....

some old fords used 18mm spark plugs...which are EXACT threads for an o2 sensor...

we have a ford spark plug thread repair kit at work, and it works on o2 sensors as well...

(most newer cars use 14mm apark plugs BTW)

Oct 8, 2004 | 06:01 PM

~~egp320i~~

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From: Central Idaho

thanks

knowing that is a big help, i figured the head is 22mm so its going to be around 17/18 or so.
any idea on the threads? they are pretty heavy duty so it should be a course thread then vs a fine thread or does it matter with a tap?
I have never really used a tap before so this is all new to me.

Oct 8, 2004 | 07:37 PM

teabagger

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thought it was 14mmx1.5?

Oct 8, 2004 | 08:21 PM

SLAB

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yes it does!

bring the O2 sensor to the hardware store (going to have to look pretty hard to find one with a tap like that) and they can tell you what thread size it is...

OR you can take the old sensor, clean the threads with a wire wheel, and then cut 2 slits 180 degrees apart on the threads themselves and then use that to clean the threads in the exhaust...

OR, take it to a muffler shop and have them do something, because that will be cheaper, and easier than buying an 18mm tap that you will only use once...