I have a 99 k1500 suburban 5.7l gas engine. I am trying to replace the rear oxygen sensors and started with the "easy" one behind the rear cat. It would not budge. I used a propane torch to heat up the seat and managed about 2 turns. Now it will not move and busted a wrench on it. Any ideas on how to loosen it up to replace it?
Mike D.
More heat and some liquid or spray lube.
I don't think propane will get it hot enough. You need to heat the bung it's in, not the sensor itself. Heat, lube, repeat.
Spray some break free or Kroil on it. Then try turning it back in some. I use a heavy duty flair nut wrench to break them loose. You could make one by grinding a notch in a box end. It only has to be wide enough to get the wires through.
Propane was getting the bung red hot. I avoided the sensor.
If you're going to be replacing the sensor, just cut the wires and use a proper box-end wrench on it. A box-end that has been cut is not strong enough, in my experience. And as was already suggested, turning it in a bit before you continue out should help.
Ray
Use lots of PBBlaster, let it soak. Then use the box end, and turn it in then out, repeat until you get it going. Sort of like pumping a old well.
Cheers
Just got some. I miss the straw. Wasting a lot on the floorboards as I attempt to aim the "pinpoint" stream at the sensor :( I'll soak them a few days and see what happens.
If you're removing it for replacement, just cut the wires off the sensor and use a regular box wrench on it. You only need to get around the wires if you plan to reuse the sensor.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.