O2 Sensor Replacement Techniques

[fcasta308]

Hello all, for all of those living in the rust belt, working with rust is only half of the work sometimes. That being said, I have a brand new O2 sensor that my daily driver LeBaron is begging me to install. The problem is that the old sensor is clearly seized from rust and the heat cycles from driving. The previous owner must have attempted to remove it and given up because the wires were cut and then put back together with electrical tape.

I'm looking for any advice, techniques and alternatives in getting this O2 sensor removed. I've been soaking it with PB Blaster right before driving it for about a week now, hoping that as it heats the PB Blaster penetrates more and more of the rust. I'd like to avoid torching it since it's IN the car still.

All help is appreciated!

[dwh4784]

The best luck I ever had doing it in car was with an offset box end wrench. Otherwise I pretty much always put a new one in any time I have the engine out "just in case".

[ajakeski]

Penetrating oil isn't going to do it. You'll need to heat it with an oxyacetelyne torch.
That's the only way I get my rust belt o2 sensors to budge.

[zin]

Another, less conventional technique, which I've never had to try (thankfully) would be "pickling". Basically soaking the joint in hydrochloric acid to remove the rust, something like CLR might work too, but would be much weaker.

If heat isn't an option (and I would try that first), chemistry can be your friend... http://www.welding-advisers.com/Pickling.html

Best of luck!

Mike

[fcasta308]

Keep the suggestions coming please!
The wrench is similar to the "O2 sensor tool", only difference being the notch cut out to avoid cutting the wires ahead of time.
An oxyacetelyne would be ideal, but unfortunately not in my budget at this time. Although worst case scenario may be to at least rent one out.
The pickling process sounds insane (and I read that whole article)! But I appreciate the suggestion!

I'm also considering either the offset wrench/O2 sensor tool/breaker bar plus a long pipe attached at the end to increase the lever arm. Though I had a friend that twisted the breaker arm drive from how much force was applied... and his O2 sensor still didn't budge.

[83scamp]

I know you don't really want to go that route, but heat is your friend...

[supercrackerbox]

A mapp gas torch can be effective, and can be bought at most hardware stores for around $20. While not nearly as hot as acetelyne, it is much hotter than propane, and mine has served me well. Look for the yellow bottle.

[marc]

I cut the top of the old O2 off. A regular six point 1/2" drive socket and a long beaker bar works for me!

[zin]

If all else fails... Time for a 3" wastegate!...

Or if that's not in the budget, leave it there and have a new bung welded into the down pipe and roll on!

Mike

[going4speed]

Something that has worked for me is to do a tighten cycle first. I know it's counter intuitive but I find it helps to break lose the sensor before removal.

[zin]

+1 to this, just don't get carried away.

Mike

[thedon809]

One of my favorite tools for getting stuck/stripped bolts out is the ole air hammer but don't know if you have access to air.

[TheCanadian007]

Heat and penetrating oil. Heat it up, apply a penetrating oil like Deep Creep or PB Blaster, then heat again. Go back and forth, and then try loosening it with a breaker bar. Keep repeating until it budges. You can also get fancy penetrating oil that uses a refrigerant as a propellant, so it actually freezes the joint to try and break the rust seal. Heating it and then freezing it would be ideal.

[fcasta308]

I appreciate every single one of your posts, there's a lot of great info on here.
Since this is my daily driver I'll begin the attempt this Saturday but at least now I don't feel that nervous about cutting those wires! Thanks to all!

[going4speed]

Another thing that can work if you dont go crazy is tapping around the sensor with a hammer. By that I mean just around the outside area around the sensor not the sensor itself. The light shocks can help break lose the rust sieze.

[BIGBRUDDA]

I cut the top of the old O2 off. A regular six point 1/2" drive socket and a long beaker bar works for me!

Ditto Then get your nephew/ friend to lay underneath and square up the wrench. drop a cable-rope-chain down thru the belt maze and cinch it around the end of the breaker bar. insert stick or bar thru top end of said contraption . Get wife or other accomplice to take pics of you doin 2 handed curls with the handle.
Sound hokie ,but its about the only way to get more than 50 lbs torq on the wrench layin in the driveway.

[shmedley]

Keep the suggestions coming please!
The wrench is similar to the "O2 sensor tool", only difference being the notch cut out to avoid cutting the wires ahead of time.
An oxyacetelyne would be ideal, but unfortunately not in my budget at this time. Although worst case scenario may be to at least rent one out.
The pickling process sounds insane (and I read that whole article)! But I appreciate the suggestion!

I'm also considering either the offset wrench/O2 sensor tool/breaker bar plus a long pipe attached at the end to increase the lever arm. Though I had a friend that twisted the breaker arm drive from how much force was applied... and his O2 sensor still didn't budge.

Tell Jakub he really needs to stop getting the chinharbor freight breaker bars. I got a good breaker bar you can use if you want to

[dwh4784]

Yeah, I broke a 1/2 drive Harbor Freight breaker bar once. The 3/4 stood the test though. That was attempting to break loose the drivers side axle nut on my 99 Ram. I had two 220lb friends jump up and down on it and it didn't budge. Left it overnight with a floor jack pushing UP on it bending the breaker bar in a U shape. It was flung across the shop in the morning but the nut was loose!

[ShelGame]

I always just break the top end of the sensor off with my favorite tool - a hammer. Break off everything except the nut - the stainless, ceramic, all. Then you can put a shorty socket on there. The bashing with the hammer helps to loosen it up, and the shorty socket gets better leverage. I've never had to soak one or use heat.

[fcasta308]

Thank you all again for the suggestions. Since this is my daily driver I get a little nervous about starting a project unless I have the means to finish it! But much appreciated to everyone, I have a lot to try for one weekend!

Brad... I almost fell off my chair laughing that you knew the person with the twisted breaker bar.