If you use sealant past the catalytic converter, don't worry about fouling the 02 sensor. If you use the sealant by the flex pipe... well you know the answer to that.

Although I must say I haven't heard of clamps purposely being a tad loose to drain excess water, at least on cars.

First time for everything ay.

 

Yeah seems silly, especially once the silicone is dry.

I don't think the exhaust is supposed to drip, either.

I just tried again using paste and the car is drivable but leaking. At least now I can drive to Advance Auto and get some high temp silicone and some beer for afterwards.

 

You should get heat wrap while you are at it. Get bigger clamps also. Wide ones. You wrap the pipe over and over till you get a nice tight bandage in a sense. Then you slide your clamp over that and tighten it.

These are the types of clamps I am speaking of.

Vibrant Performance ::.

 

I'll use the heat wrap. I've also ordered a tail pipe expander tool to get the pipe as round as possible.

 

So I finally got the exhaust clamps in place and fully sealed. I didn't think this would be such a pain. What I learned:

+ A cheap tranny jack with a strap is useful if you're dropping the exhaust solo.
+ Critical: Grind off as much of the corrosion and previous sealant as possible. Sand and then degrease the pipes after grinding.
+ Use new clamps.
+ If you're getting your adhesive at Autozone, use the sticky gray Permatex exhaust putty and not the useless blue Permatex sealant, which is liquid.
+ During re-installation, apply putty and install the clamps onto the header/cat pipes first.
+ Apply putty on the exposed inside area of the clamps.
+ Apply putty to the cat back pipes and slide into the clamps on the header/cat pipes.
+ Quickly, before the putty dries too much, install the exhaust hanging hardware.
+ Untighten the front bolts on the clamps, then start tightening all the bolts evenly.
+ Tighten until snug and then give it a little more until the bolts are just very tight -- watch the clamps and make sure the sleeves don't deform.
+ Wait a few minutes for the putty to set up a little, then run the engine at idle only for 10 minutes.
+ Check for leaks.
+ Turn the car off and set sit overnight before driving.

Note that one of the cat back pipes was deformed a little, so I bought an exhaust pipe expander and used it, but the pipe pinged and sounded like it was going to crack, so I stopped there.