Removing insanely tight o2 sensor

[NewKleer]

I got a new o2 sensor recently for my r31 skyline (rb20det nics redtop). Anyway to cut to the chase, we cracked a clean break down the side of the 21mm (or whatever) o2 sensor socket in trying to remove the o2 sensor...first time id ever seen one break

so how would i remove the sensor (preferably not taking the dump pipe off) if its on so tight it breaks sockets?

[MANWHOR3]

I can't remember what the stuff is called, but it's sold in Autobarn. Ask them, they'll know. It's this thing you apply to it to dissolve the rust and lubricate the thread.

[vas_95]

I can't remember what the stuff is called, but it's sold in Autobarn. Ask them, they'll know. It's this thing you apply to it to dissolve the rust and lubricate the thread.

a liittle wd 40 goes a long way

[predator]

you cracked the socket?? never seen that happen before, must have been some pretty weak metal. Usually the thread will just sheer.

Did you use a breaker bar?? You *were* going anticlockwise right?

[MANWHOR3]

It's not wd40. I tried wd40, and it did not penetrate that well. It was something else.

[NewKleer]

yer i cracked the socket - o2 sensor sockets are a bit weaker than usual to start with due to the slit in them for o2 sensor wires. used a breaker bar, anti clockwise. this was a pretty heavy duty socket too, hence my surprise

any chance having the engine running (heating exhaust) helps at all?

[gtrGhosTDoGG11]

Heating it will make it expand and be harder to take off, also burning your hands off. Do it when its cold would be better. Keep trying.

[=premo=]

i had the same problem with mine last nite (didnt break the socket, just rounded the nut a bit), socked it in crc and half hour later came back, instead of undoing it i tried doing it up a little first (slightest bit) and then hit the dump pipe with a small hammer near the sensor, sparayed a bit more crc and another half hour later came back again and it came out. althow i wont be able to use the nut again as it folded in whilst i was undoing it (didnt matter as i welded a new one in my new dump).

[GTaaargh]

You might try some stuff called KoperKote - I might have the spelling wrong. It penetrates so well you can't keep it in the tube

[SECURITY]

when i was taking my o2 sensor off i snapped off the bit before the nut, the ceramic part. then put on some wd40 and ran the car for a minute or so, removed my turbo heat sheild and used a rachet to get it off.

[NewKleer]

just an update, i used some rost off, cut the wires off the sensor and used a proper socket, finally came out

[lwells]

I can't remember what the stuff is called, but it's sold in Autobarn. Ask them, they'll know. It's this thing you apply to it to dissolve the rust and lubricate the thread.

Are you thinking of Penetrene?

NewKleer: Out of interest, where did you buy the socket?

Lucien.

[B-Man]

inox

Also - heating it should help - well it helped me remove stubborn turbo bolts.

[NewKleer]

my brother had the socket...im not sure - it was a black one if that helps. im guessing the other socket cracked as it was the socket with the gap for the o2 sensor wires, and hence is fundamentally weaker due to that gap.

i also have to turn the car around before removing it, thus the exhaust would have been lukewarm. seemed to come out with too much trouble with the rost off/warm/better socket combined