spradilak
Newbie
Will do, thanks! Also I did find that tap, they've got it at the parts store and it's specifically called an 7/8" o2 thread chaser.
Exhaust leak after replacing Intake Manifold gaskets
- Thread starter spradilak
- Start date
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spradilak
Newbie
Bam and you're right again, grabbed a 1/4-28 nut from Ace and it's a perfect fit until I find a wing nut, thanks again!
Unless you can get to the backside of the O2 sensor remnant, so you can wet the threads from the inside of the pipe, penetrating oil is a total waste of your time.
The threads are sealed with a gasket, exactly like old-style gasketed spark plugs. The seal is air-tight. Penetrating oil cannot get into the threads to do any good until you've already backed the sensor out a half-turn or so. By then, you don't really need the penetrating oil. The penetrant does make a lovely puddle on your driveway, though.
If your manifold isn't bolted to the head air-tight, you'll get leakage out...and air leakage in. This can screw-up the O2 sensor signal, leading to false "lean" readings; and then the computer adds more fuel to compensate.
Make plans to remove the manifold, and remove the broken bolts. Get the manifold planed if it's to be re-used, or find a replacement. Any way you look at this, the exhaust system needs to be sealed-up AT LEAST to the catalytic converter, and ideally to the end of the tailpipe.
The threads are sealed with a gasket, exactly like old-style gasketed spark plugs. The seal is air-tight. Penetrating oil cannot get into the threads to do any good until you've already backed the sensor out a half-turn or so. By then, you don't really need the penetrating oil. The penetrant does make a lovely puddle on your driveway, though.
If your manifold isn't bolted to the head air-tight, you'll get leakage out...and air leakage in. This can screw-up the O2 sensor signal, leading to false "lean" readings; and then the computer adds more fuel to compensate.
Make plans to remove the manifold, and remove the broken bolts. Get the manifold planed if it's to be re-used, or find a replacement. Any way you look at this, the exhaust system needs to be sealed-up AT LEAST to the catalytic converter, and ideally to the end of the tailpipe.
spradilak
Newbie
Well I guess I'm just gonna crank on it with my 1/2 breaker bar with a fence post over it..that should remove what's left of the o2 sensor hopefully. I can spray the pb blaster into that hole, not sure if that would be any more effective.
As far as replacing the broken bolts that'll be something for me to unfortunately take to a make or a shop where they can try the welding a nut onto them thing to get them off that way.
I really don't have even a glimmer of hope for trying to extract those myself. Another member mentioned some type of exhaust manifold clamp. Not really sure what that is but I suppose it's worth looking into.
That was me, about the clamp. I have one on my 5.3 engine Tahoe. They only work on the ends of the manifold. I am unsure if they are made by anyone for the 5.7 engine.
As far as having to break the sensor housing loose to allow for penetrant to get at the threads, I disagree. That is an old threaded connection, that has expanded and contracted literally thousands of time and been subjected to engine vibrations and whatever crap the elements can throw at it too. That penetrant is made to "creep' in to the smallest of areas to reach the threads. I have used Kroil for many years and still say it works best but others have said PB Blaster is good too. Let's put it this way, "it cannot hurt to try". No doubt, when loosened a little and a bigger gap is exposed, even better, but I think the initial attempt of Kroil is worth the shot. This is IMO, of course.
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If exhaust gas--hot and extremely low viscosity, and under slight pressure due to exhaust restriction in the catalyst and the muffler--can't get out...penetrating oil that's thicker and under no pressure but gravity, can't get in.
Best be careful. What's left in the man. is just a thin,threaded shell. It will snap right off if your not careful.
We can agree to disagree. I don't doubt what you say as much as I think it is worth a shot. In my over 40+ years in the industry and close to 50+ years around vehicles and in shops, I have been wrong oh so many times.
spradilak
Newbie
Yeah I'm nervous about that and after my previous experiences with this truck..its what I expect. But I don't really see any other options. Gonna let the truck warm up for a few minutes first aswell.
spradilak
Newbie
Just wanted to update all you fine folks that helped me in this post. Drove the truck for about 10 minutes to get the ezhaust heated up a little. Got the old o2 sensor out easily and got the threads in the manifold cleaned up with the o2 sensor thread chaser. No more exhaust leak it's beautiful. Thanks again!
