How to replace O2 housing (pics)
Feb 17, 2008, 07:59 PM
#1
How to replace O2 housing (pics)
The o2 housing isnt that bad, some people will not do it unless changing some other components along with it. I had no trouble changing it, as long as I had a blowtorch and the right tools. You could however, take this time to also change your Exhaust Manifold, Downpipe, Maybe even your Hot-section. But it's not that bad and probably takes 5-10 hours your first time doing it. But who doesnt like working on their car?? To continue Read on....
How to replace your O2 housing.
This guide is based on a 9, should be the same for the 8, but do not quote me on that. In this guide I remove a ported stock housing, and replace it with a Megan housing. (The megan is identical to most o2 housings such as the Ebay, and various manufacturer's housings, the issued would be with a cast housing, such as the Works or similer. The only difference being I think you reinstall the L bracket to the block and the tube/pipe type you leave it off). Lets get started..
Dont make plans for a whole weekend, you never know how this could go. Do have extra transportation, I must have been at the parts store 5 times, I may have forgotten something in the guide, like needing a particular size wrench or something, so be ready. Its all there though.
Required Tools
lots of
.New O2housing + Gasket (should come with one)
Floor Jack and some Jack-stands.
Blowtorch (yes this is absolutely necessary)
PB-blaster (needed as well)
Shallow metric sockets from sizes 10mm to 19mm.
Wrenches from 10mm to 19mm.
Open end O2 sensor socket (or open end 22mm wrench)
Flathead and Phillips screwdrivers
Anti-seize bolt lubricant (use it or you will hate yourself later)
2 Gal of Antifreeze, and 2 Gal of Distilled water
Funnel (comes in handy)
Red RTV Silicone (recommended)
Possibly replacement Donut Gasket depending on your setup.
Getting started.
Start off by gathering the tools and jacking the front of your car up. I used the front jacking butt as shown in the service manual, then used 2 jackstands on each side of the car in the standard jacking positions. I had jacking blocks to stop it from bending the pinch welds.
Edit: Disconnect the negative(black) terminal on your battery BEFORE you try and remove/install your downpipe. Some people have hit the starter with the DP causing some electrical issues, not to mention the possibility of shock or death.
Now get up under the car and get your downpipe out of there. Remove it from 2 rubber hangers, remove 2 bolts from the DP-O2 housing, then remove it from the Cat and place it aside. Your experience will vary depending on the Downpipe you have installed.
This is my DP, it is a pain to remove with all of those wires... Once your pipe is out check the O2 housing for the Donut Gasket, It might look like part of the housing due to dirt, but it is not, gently pry it off with a flathead, If your using the stock Gasket, you are probably going to need to replace it. Mine was a week or two old, so I re-used it. if it breaks or wont come off, turn back now and get a new one.
Now look at your new O2 housing, try to slide the donut gasket on, does it fit? My qtp gasket would not, so I ported the inside of it about 1mm. You may not have to. I used a dremmel on low with one of those barrel-shaped sanding cylinders. It took about half an hour.
Now that you have all of the proper fitting parts go ahead and run a 1mm dia. bead of the red rtv around the bottom of the donut gasket where it will sit flush with the O2 housing. Press on the donut and sit the housing aside to dry.
Removing the Radiator, Intake, and other stuff
I tried to do this without removing the radiator, but I swear to you, if you remove it, it will save at least 2-3 hours of work, plus you wont damage it.
Start by draining the radiator, after the car has cooled for 4 hours or so climb under and on the passengers side at the back of the radiator you will see a little hex-shaped plug with a small tube under it facing down. Put a bucket (or whatever) under the tube and use a phillips driver or wrench to loosen the hex-nut. Once you see a drop, go to the top of the radiator and remove the radiator cap. Not the tube should be flowing with fluid. If you loosen the bolt too much, it will flow out the back and get all over the place, be carefull with that.
Wait a while (around 20 mins) for the radiator to empty. While it is draining go to the top of the engine and start removing the Upper Manifold heat shield. There is a clip with a wire and about 3-5 bolts. It is pretty straight forward to remove. Get it out and set it aside, then have a
, now remove your intake piping. You may have to remove your UICP depending on your setup. This is pretty straight forward, and only done to get the radiator out.Now that the radiator is empty, disconnect the 2 bolts holding the brackets/hose from the radiator cap area to the overflow tank at the left of the enginebay. Then remove the overflow tank cap (just pull it off). Now remove the upper radiator hose, use a pair of pliers to pull back the latching clamp and slide the hose off. Once it is off stuff a papertowell into the hole to stop it from leaking all over your engine. Now do the same for the lower pipe. While you are down there you will see the bottom of the fan, and a little bracket with wires hanging off it. There is a grey electrical connector for the fan. Disconnect it, then disconnect that wire from the bracket by pulling the plug/bracket rubber part out.
Now back to the top of the radiator. Disconnect the 2 bolts on the front frame holding the radiator stoppers to the frame. Now remove both left and right stoppers, then pull the radiator out. It will be leaking crap everywhere, so before you move it, stuff a papertowell in the lower radiator hose hole. Pull it straight out, fan and all and set it aside.
Now take a look at all of that space you have in there! Refreshing!
Now that the radiator is out go ahread and disconnect all the bolts on the lower heat shield, Dont remove it, just disconnect it, because the O2 sensor wire is still in the way.
continued next post.......
Last edited by Jameson_IXMR; Feb 29, 2008 at 12:25 PM.
Feb 17, 2008, 08:34 PM
#2
Don your protective goggle and blowtorches, it's time for the fun part!!
First things first, go ahead and spray all 5 bolts holding the O2 housing to the Hot-section with PB blaster, and let soak for about 45 minutes. I suppose you could do this before removing the radiator and all that, hopefully you read this whole thing before starting! Let the Blaster do its thing, then get in there with a papertowell and wipe it all off, be sure to get it all off, that stuff is flamable!!
Now put on some safety goggles (seriously, dont want rust in your eyes!!!)
Light your blowtorch and start heating the O2 housing where it meets the O2 sensor (do not heat the sensor, only the housing). Once you start to see specks of hot iron quickly turn off the heat and get a 22mm wrench on the sensor. It should come out with practically no effort. Count how many rotations it takes to get it out and remember that number. Pull the sensor out of the heat shield, remove the lower heat shield, then place the sensor up somewhere safe, I tucked mine neatly near the intake manifold, on a papertowell.
There are 3 bolts on the upper part of the O2 housing, you will need to heat the O2 housing (not the bolts) then get a wrench on them and brake them loose, do not remove them yet. It works just like the O2 sensor did.
Once those are loose, get at the 2 lower Nuts, this time heat the Nuts, not the O2 housing, and get a wrench on them to break them loose. It takes some maneuvering to get to some of these. I used wrenches and shallow sockets for everything, it is a tight fit, but it is possible. For the one in the back bottom, I used a wrench between the number 2 and 3 exhaust manifold runners and that worked well.
Now that all of your bolts are broken loose take a little break, get some lunch, relax!! This takes some time to get done!
First things first, go ahead and spray all 5 bolts holding the O2 housing to the Hot-section with PB blaster, and let soak for about 45 minutes. I suppose you could do this before removing the radiator and all that, hopefully you read this whole thing before starting! Let the Blaster do its thing, then get in there with a papertowell and wipe it all off, be sure to get it all off, that stuff is flamable!!
Now put on some safety goggles (seriously, dont want rust in your eyes!!!)
Light your blowtorch and start heating the O2 housing where it meets the O2 sensor (do not heat the sensor, only the housing). Once you start to see specks of hot iron quickly turn off the heat and get a 22mm wrench on the sensor. It should come out with practically no effort. Count how many rotations it takes to get it out and remember that number. Pull the sensor out of the heat shield, remove the lower heat shield, then place the sensor up somewhere safe, I tucked mine neatly near the intake manifold, on a papertowell.
There are 3 bolts on the upper part of the O2 housing, you will need to heat the O2 housing (not the bolts) then get a wrench on them and brake them loose, do not remove them yet. It works just like the O2 sensor did.
Once those are loose, get at the 2 lower Nuts, this time heat the Nuts, not the O2 housing, and get a wrench on them to break them loose. It takes some maneuvering to get to some of these. I used wrenches and shallow sockets for everything, it is a tight fit, but it is possible. For the one in the back bottom, I used a wrench between the number 2 and 3 exhaust manifold runners and that worked well.
Now that all of your bolts are broken loose take a little break, get some lunch, relax!! This takes some time to get done!
Feb 17, 2008, 08:42 PM
#3
Take this time to get under the O2 housing, you will see an L-shaped bracket like so...
Get on the 2 bolts on that bracket with a wrench, remove the bracket entirely. If you are using an O2 housing that uses this bracket remember to re-install it once you put the new one on. Otherwise just ignore that.(Most dont use the bracket)
After the O2 housing has cooled down from the stern blowtorching you gave it earlier, go ahead and remove the lower nuts, and set them aside. Then remove the 3 Top bolts and be ready to catch the O2 housing, otherwise it will just fall to the ground. Set those bolts aside as well as the housing and gasket that came off of your car.
You should now have something that looks like this.......
and another view! Congratulations you are about 1/2 way through.
lets continue......
Get on the 2 bolts on that bracket with a wrench, remove the bracket entirely. If you are using an O2 housing that uses this bracket remember to re-install it once you put the new one on. Otherwise just ignore that.(Most dont use the bracket)
After the O2 housing has cooled down from the stern blowtorching you gave it earlier, go ahead and remove the lower nuts, and set them aside. Then remove the 3 Top bolts and be ready to catch the O2 housing, otherwise it will just fall to the ground. Set those bolts aside as well as the housing and gasket that came off of your car.
You should now have something that looks like this.......
and another view! Congratulations you are about 1/2 way through.
lets continue......
Last edited by Jameson_IXMR; Feb 17, 2008 at 08:45 PM.
Feb 17, 2008, 08:58 PM
#4
Installing the new Housing!
Okay, now take the Original 3 bolts and 2 nuts from the O2 housing, coat the threads well with anti-seize lubricant (available from any autoparts store). use a papertowell to wipe away the excess very well, it doesnt take much, wipe it off with some pressure and it will come off and penetrate the threads at the same time.
Make sure your O2 housing/Hot-section/and gasket's are clean then continue. If not wipe away any debris with some carb-cleaner and a paper-towell.
Now stick your new O2 housing up there with the new gasket between the hot section and housing. Stick in the top bolt and make it hand-tight. Now install the other 2 bolts the same way, and also the 2 nuts. Go back around and hand tighten all of the bolts.
Now get a torque wrench and use a star-like pattern to start torqing the bolts/nuts in place. I realise it is impossible to get a torque wrench on some of the bolts, just make sure those feel about as tight as the rest. It is important to use the star-pattern so the gaskey seals evenly. Torque the bolts to about 28-32 lbs. I forget the actual torque value so make sure you double check this with the service manual, easily found on the internet, and these forums.
Once your new housing is installed, you should have something that looks like this!!
Your almost there!!!
Now remember when you counted how many turns to get the o2 sensor out? Well guess what, rotate the o2 sensor that many turns in the opposite dirrection, then install it into the new O2 housing. This will keep your wires straight. Then tie and wires out of the way of the exhaust parts. If you install the Upper heat shield it has a clip for the wire, but it will still need zip-tying towards the bottom and top near the valve cover.
continue......
Okay, now take the Original 3 bolts and 2 nuts from the O2 housing, coat the threads well with anti-seize lubricant (available from any autoparts store). use a papertowell to wipe away the excess very well, it doesnt take much, wipe it off with some pressure and it will come off and penetrate the threads at the same time.
Make sure your O2 housing/Hot-section/and gasket's are clean then continue. If not wipe away any debris with some carb-cleaner and a paper-towell.
Now stick your new O2 housing up there with the new gasket between the hot section and housing. Stick in the top bolt and make it hand-tight. Now install the other 2 bolts the same way, and also the 2 nuts. Go back around and hand tighten all of the bolts.
Now get a torque wrench and use a star-like pattern to start torqing the bolts/nuts in place. I realise it is impossible to get a torque wrench on some of the bolts, just make sure those feel about as tight as the rest. It is important to use the star-pattern so the gaskey seals evenly. Torque the bolts to about 28-32 lbs. I forget the actual torque value so make sure you double check this with the service manual, easily found on the internet, and these forums.
Once your new housing is installed, you should have something that looks like this!!
Your almost there!!!
Now remember when you counted how many turns to get the o2 sensor out? Well guess what, rotate the o2 sensor that many turns in the opposite dirrection, then install it into the new O2 housing. This will keep your wires straight. Then tie and wires out of the way of the exhaust parts. If you install the Upper heat shield it has a clip for the wire, but it will still need zip-tying towards the bottom and top near the valve cover.
continue......
Last edited by Jameson_IXMR; Feb 17, 2008 at 09:33 PM.
Feb 17, 2008, 09:10 PM
#5
Re-installing the radiator!!
Get your radiator from whatever safe place you put it and sit it back in the car. There are two little holes at the bottom of the enginebay, and two little rubber circles on the bottom of the radiator, put the circles in the holes, very simple. Now put on the two upper radiator mounts/stoppers, and put the 2 bolts back into the frame. Tighten those down.
Take all of the papertowells out of the hoses (make sure you get them all) then connect the upper and lower hoses to the radiator, use pliers to put the clamp back over the radiator inlet.
Now put the 2 clamps on the overflow hose back on the frame and bolt them in. Then put back on the overflow-cap. It just pops on easily.
You can now install your upper heat shield if you like, you can probably kiss your lower shield goodbye, as it will not bolt up anymore, unless you are using a stock O2-housing. Tighten all the bolts if you do this.
Re-installing your downpipe.
Pretty straight forward, your might be different. Put it in place, hold the front up, connect it to the Cat (dont forget the gasket). Then connect it to the rubber hanger(s). Now bolt it up to the new O2 housing, make sure, absolutely sure, you torque this correctly or it will leak. Make the bolts hand tight, then alternate giving each one 1/2 a turn, back and forth, so it goes on evenly. Be sure it seats to the donut gasket already installed on the O2 housing from earlier. I torqued mine to 37lbs, check with the maker of your downpipe for this number. A leak here will mess up your AFR's as well as make your engine dirty as sin, real fast. Also it can leak out onto the hood through the hood vent.
Once your DP is back on, go ahead and put your Intake and LICP back on. Make sure to tighten everything down really well. Might even be a good idea to perform a quick boost leak test. (search for how-to).
Get your radiator from whatever safe place you put it and sit it back in the car. There are two little holes at the bottom of the enginebay, and two little rubber circles on the bottom of the radiator, put the circles in the holes, very simple. Now put on the two upper radiator mounts/stoppers, and put the 2 bolts back into the frame. Tighten those down.
Take all of the papertowells out of the hoses (make sure you get them all) then connect the upper and lower hoses to the radiator, use pliers to put the clamp back over the radiator inlet.
Now put the 2 clamps on the overflow hose back on the frame and bolt them in. Then put back on the overflow-cap. It just pops on easily.
You can now install your upper heat shield if you like, you can probably kiss your lower shield goodbye, as it will not bolt up anymore, unless you are using a stock O2-housing. Tighten all the bolts if you do this.
Re-installing your downpipe.
Pretty straight forward, your might be different. Put it in place, hold the front up, connect it to the Cat (dont forget the gasket). Then connect it to the rubber hanger(s). Now bolt it up to the new O2 housing, make sure, absolutely sure, you torque this correctly or it will leak. Make the bolts hand tight, then alternate giving each one 1/2 a turn, back and forth, so it goes on evenly. Be sure it seats to the donut gasket already installed on the O2 housing from earlier. I torqued mine to 37lbs, check with the maker of your downpipe for this number. A leak here will mess up your AFR's as well as make your engine dirty as sin, real fast. Also it can leak out onto the hood through the hood vent.
Once your DP is back on, go ahead and put your Intake and LICP back on. Make sure to tighten everything down really well. Might even be a good idea to perform a quick boost leak test. (search for how-to).
Feb 17, 2008, 09:29 PM
#6
Take a moment to be sure the following is complete...
O2 housing torqued and secure.
O2 sensor Installed good.
Intake/Upper IC piping installed.
Downpipe/Exhaust installed correctly.
Donut Gasket is seated properly.
LICP installed and tight.
All plugs/papertowells out of radiator.
Radiator Hoses are tight and clamped.
All wires (o2 sensor/MAF wires) are secure/zip tied safely.
Overflow lid is on, all brackets are secure.
Did you anti-sieze all bolts? You better have.
I may have forgotten some other stuff......
Make sure EVERYTHING is good and tight, and then continue.....
O2 housing torqued and secure.
O2 sensor Installed good.
Intake/Upper IC piping installed.
Downpipe/Exhaust installed correctly.
Donut Gasket is seated properly.
LICP installed and tight.
All plugs/papertowells out of radiator.
Radiator Hoses are tight and clamped.
All wires (o2 sensor/MAF wires) are secure/zip tied safely.
Overflow lid is on, all brackets are secure.
Did you anti-sieze all bolts? You better have.
I may have forgotten some other stuff......
Make sure EVERYTHING is good and tight, and then continue.....
Feb 17, 2008, 09:39 PM
#7
By now, everything should be good, except one thing. No coolant in the radiator!!
Get a gallon bottle of distilled water, and measure out half of it. (I just poured out half the bottle onto my plants and stuff). Now fill the other half with antifreeze so it is a 50/50 mix.
Note: Depending on where you live, you might want to mix the Antifreeze and water at a different ratio, be sure you know what your doing before you mix it. If your in Florida like me, go ahead and continue on reading now....
If everything is straight. Pour the mix into the radiator slowly!! Fill it right up to the top. It will probably take abour 1.3 USgal.
Now fill your overflow tank to about half full, between the low and full marker lines.
Put on your radiator cap, Make sure it is tight, make sure the overflow cap is on then continue....
Get a gallon bottle of distilled water, and measure out half of it. (I just poured out half the bottle onto my plants and stuff). Now fill the other half with antifreeze so it is a 50/50 mix.
Note: Depending on where you live, you might want to mix the Antifreeze and water at a different ratio, be sure you know what your doing before you mix it. If your in Florida like me, go ahead and continue on reading now....
If everything is straight. Pour the mix into the radiator slowly!! Fill it right up to the top. It will probably take abour 1.3 USgal.
Now fill your overflow tank to about half full, between the low and full marker lines.
Put on your radiator cap, Make sure it is tight, make sure the overflow cap is on then continue....
Last edited by Jameson_IXMR; Feb 17, 2008 at 09:47 PM.
Trending Topics
Feb 17, 2008, 09:57 PM
#8
Be sure that your Radiator cap is the highest point in the cooling system. If your driveway is on an incline you are probably okay, if not leave the front jacked some to make the cap the highest point. Otherwise take the car off the jackstands/jacks or whatever you used. If you hired 2 strongmen to hold the front of the car up, tell them to take the rest of the day off.
Now put your gear in neutral and leave the p-brake on (especially if you are still on jacks or a lift or something).
Start the car. Put the Heat on full hot, and turn the fan to the highest setting. Now walk over and check the engine bay again. Look for anything you may have missed. Also check for exhaust leaks with the back of your hand, do it slowly so you dont burn yourself. Watch the overflow tank, after a couple of minutes the thermostat should click and the car should start sucking in the antifreeze mix. If it needs more it will pull it from the overflow tank. Stand by for about 10 minutes and fill it as it uses it. You may not even need to fill it at all. After 10 minutes or so, shut the car off.
Now let the car cool for about an hour, then come back and fill the overflow to the full line exactly.
Put the cap back on, check everything again. Now that the pipes are warm, check the torque on the DP again if you want (I did, and would again).
Take the car off jacks if it's still up. Check under it for any fluid leaks, check your oil level just incase.
Now take her out for a 1-5 mile cruise, be easy but not too easy.
Once your done check the levels again, give your plumbing, Intercooler,Intake,and mabye even exhaust a once over with a wrench/driver, make sure your overflow-tank is still full, if not top it off with the mix.
Thats it!!! You my friend, are done! Finished!
Note: Be sure to check your fluid levels again in a couple of days in case there was any air in the system. Since you filled/started it on an incline there shouldnt me much if any.
Done!
Note: Here is an addition from WickedE...
"When you're done and satisfied... Go find your significant other and make some squishy for not spending time with her. Then have a beer..."
Did I forget anything? If so let me know!! I will update it. Hope this helps someone out, I know I couldnt find a how-to with details and pictures. If this helped you out, I would love to hear from you.
Now put your gear in neutral and leave the p-brake on (especially if you are still on jacks or a lift or something).
Start the car. Put the Heat on full hot, and turn the fan to the highest setting. Now walk over and check the engine bay again. Look for anything you may have missed. Also check for exhaust leaks with the back of your hand, do it slowly so you dont burn yourself. Watch the overflow tank, after a couple of minutes the thermostat should click and the car should start sucking in the antifreeze mix. If it needs more it will pull it from the overflow tank. Stand by for about 10 minutes and fill it as it uses it. You may not even need to fill it at all. After 10 minutes or so, shut the car off.
Now let the car cool for about an hour, then come back and fill the overflow to the full line exactly.
Put the cap back on, check everything again. Now that the pipes are warm, check the torque on the DP again if you want (I did, and would again).
Take the car off jacks if it's still up. Check under it for any fluid leaks, check your oil level just incase.
Now take her out for a 1-5 mile cruise, be easy but not too easy.
Once your done check the levels again, give your plumbing, Intercooler,Intake,and mabye even exhaust a once over with a wrench/driver, make sure your overflow-tank is still full, if not top it off with the mix.
Thats it!!! You my friend, are done! Finished!
Note: Be sure to check your fluid levels again in a couple of days in case there was any air in the system. Since you filled/started it on an incline there shouldnt me much if any.
Done!
Note: Here is an addition from WickedE...
"When you're done and satisfied... Go find your significant other and make some squishy for not spending time with her. Then have a beer..."
Did I forget anything? If so let me know!! I will update it. Hope this helps someone out, I know I couldnt find a how-to with details and pictures. If this helped you out, I would love to hear from you.
Last edited by Jameson_IXMR; Feb 17, 2008 at 10:14 PM.
Thread
Thread Starter
Forum
Replies
Last Post
joel(PA)
Evo X How Tos / Installations
66
Mar 9, 2018 06:10 PM
halfnhalf83
Evo Engine / Turbo / Drivetrain
31
Oct 7, 2015 08:23 PM
MitsuJoe
Evo How Tos / Installations
1
Aug 1, 2004 01:59 PM
