4 replies to this topic

[pauldridge]

Many contributors have discussed the difficulty of getting an old O2 sensor out.  And, not surprising.  Many of these sensors have been in place since new, and are virtually welded in place by years of heat and rust.

 

Common wisdom is that removing the entire intake/exhaust manifold for proper access is the way to go, but that is a daunting task at best.

 

Determined to do it the easy way, I first acquired one of those special O2 sensor sockets, the type with a slot cut in one side to clear the permanent wires connected to the sensor.  These are just a few dollars (pounds) and I can't imagine how a sensor could be removed without one.

 

The problem is, most of these socket/tools come with a 3/8" drive slot, and that is just too small for the torque required to remove these sensors.  I tried first manually with a big breaker bar on a 12" 3/8" extension.  But there was just too much flex in the extension to make any headway.  So, next, I broke out my 1/2" air impact gun, and used a 3/8"-to 1/2" adapter at the socket to accommodate a 1/2" extension.  I pounded away with the gun for many seconds, until finally the 3/8" tit on the adapter failed and snapped right off.

 

Not to be defeated, I took the remains of the 1/2" adapter, and MIG welded that baby right to the O2 socket.  

 

(In hindsight, I now see that I could have spent just a few more bucks and gotten a 1/2" drive socket to begin with.. here's one on Amazon for about $13 US: https://www.amazon.c... 1/2 inch drive

 

Then I enlisted the aid of "Big Bertha", my gonzo, 3/4" drive impact gun (with appropriate step-down adapter) to my beefed up sensor socket.

 

Man, it just took a short blip on the gun trigger and that baby came right out.

 

The lesson learned, you just need appropriately sized tools for the job!

 

Even if you don't have a pressurized air supply at your home garage, it would be worth it to take your Mini around to a local garage that has a serious air impact gun.  No doubt they will be able to pop it right out and save hours of time.

 

IGNORE THE FOLLOWING IMAGES.. THEY WERE INTENDED FOR ANOTHER POST

Edited by pauldridge, 29 August 2017 - 10:11 PM.

[AeroNotix]

I don't really think taking the manifold out to get a stubborn lambda sensor out is all that of a pain.

 

The issue with working on the mini is the cramped, tight spaces with all manner of surfaces ready to graze your knuckles. You want to prioritise giving yourself room where you can. Make it easy for yourself.

 

Welding a custom socket together compared to either taking the manifold out or cutting your losses and cutting the wires to get a normal socket on there? Not worth your time!

[panky]

Great idea, always good to develop new ways of doing things. 

[pauldridge]

It took me literally 5 minutes to weld up that socket (but then a wiser person, following my advice, would just buy the 1/2" socket to begin with (and dispense with the need for a welder).  Can you remove (and reinstall) manifolds in 5 minutes?  My sole purpose of posting this was to save others from the false steps I initially took.  With the proper tool, at an expenditure of roughly 10 quid, the entire job should take less than 10 minutes.

 

One of the advantages of removing the sensor "in situ" si that you DON'T have to work in tight cramped spaces and bloody your hands.  A simple 12" long extension for the socket, and all the work is done well above the engine.

 

To each his own!

 

I don't really think taking the manifold out to get a stubborn lambda sensor out is all that of a pain.

 

The issue with working on the mini is the cramped, tight spaces with all manner of surfaces ready to graze your knuckles. You want to prioritise giving yourself room where you can. Make it easy for yourself.

 

Welding a custom socket together compared to either taking the manifold out or cutting your losses and cutting the wires to get a normal socket on there? Not worth your time!

[minimans]

Well to be honest I've been working with O2 sensors for many years and I've never come across one that needed a 3/4 impact gun to remove it! I have a O2 sensor wrench that is basically a big line wrench but swivels at the end for tight access and that always works for me. I'd be worried about damaging the bung or threads putting a huge gun on it?