Now with the efi system I'm starting to keep careful track of what rtv I use on the engine.
I went to the local kragens and bought 3 tubes of permatex rtv, one ultra copper, one ultra black, and one ultra blue (no reason in particular, I just wanted to use multiple colors for the heck of it )

Heres the skinny:
Ultra Copper:
Card and tube says it is sensor safe, and card/tube have matching part #.

Ultra Blue:
Card and tube says sensor safe, card/tube have different part #. (No R at the end of it on tube)

Ultra Black:
Card only says sensor safe. card/tube have different part #. (No R at the end of it on tube).

So... which do I believe? These discrepencies also match the pictures on permatex's website.

Oxygen sensors have been used for about 20 years. I can't imagine that a top notch supplier like Permatex would still be selling RTV that wasn't sensor safe. Especially if it states that it is sensor safe on either the package or tube. That's the kind of thing that a trial lawyer could use to make millions.
Bob D

Bob,
Agreed, I'm not a trial lawyer out to make millions I just don't want to hose the o2 sensor
Come to think of it, assuming any rtv gets into the water/oil stream, and does combust, which fumes travel down the exhaust ... the probability of all that is extremely low.

I have been using all three of those products for years on O2 equiped cars and have never had a sensor problem.

FWIW, I like the Ultra-Black the best. It seems to have the most stick when it comes out of the tube to help hold gaskets in place.

_________________

Dave Clement
68 Barracuda (Hot-Rod \6)
http://mysite.verizon.net/vze4pgxf/