On Thu, 2 Aug 2018 03:31:58 -0000 (UTC), Arlen Holder
wrote:
Car is just bought by a kid just learning to drive (he's 16).
2004 Mitsubishi Lancer ES
Neighbors asked me to teach him how to replace the oxygen sensor (due to
emissions code).
The threads were stripped and "filled" with some kind of hardened "metal
paste".
The new part is a Denso 234-4739 (marked 485000-4060, 07U05)
The old part is a Denso (marked 234000, 8643, 07E23)
What would you suggest?
- Tap the threads? (22mm hex nut)
- New exhaust manifold?
http://www.bild.me/bild.php?file=3234632o2sensor01.jpg
http://www.bild.me/bild.php?file=8064061o2sensor02.jpg
http://www.bild.me/bild.php?file=6399144o2sensor03.jpg
http://www.bild.me/bild.php?file=1574232o2sensor04.jpg
http://www.bild.me/bild.php?file=9418974o2sensor05.jpg
http://www.bild.me/bild.php?file=4183674o2sensor06.jpg
http://www.bild.me/bild.php?file=5856176o2sensor07.jpg
http://www.bild.me/bild.php?file=3486734o2sensor08.jpg
http://www.bild.me/bild.php?file=9694112o2sensor09.jpg
http://www.bild.me/bild.php?file=5019152o2sensor10.jpg
First of all, it does NOT appear the threads in the manifold are
stripped or damaged - but some ham-fist crossthreaded the sensor,
stripping the threads off of it, then tried to "glue" it back in.
Get a tap to fit the threads and chace all the crap out of the
threads. BE CAREFULL to get it in SQUARE and not to recut the threads
in the manifold. After chasing out the threads you should have, if
not a full thread, at least enough thread to hold the new sensor
firmly in place.
If, by some chance you find the thead IS too badly damaged, now is the
time to find out how heli-coils or Speed-serts work. These are thread
repair devices that involve retapping the hole to a larger size with a
specialized tap, then installing an insert into the hole to restore
the thread to the original size and form.
It's a handy process to learn. - but requires some rather pricey
tools that you may never need to use again - - - so would likely be
"smarter" to have an expert (read that as someone who has the required
tools and has done it before) do the job for you.
The tap required to chase out the thread will be metric - usually an
18mm spark plug tap. (or thread chaser)