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DISCUSSION => Engine + Driveline => Topic started by: adam12hicks on June 08, 2008, 09:20:25 AM

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: adam12hicks on June 08, 2008, 09:20:25 AM

So when I pulled my throttle body heater pieces there were two metal gaskets between the throttle body heater and intake manifold, and it was covered in red rubbery gunk.  When I reassemble my intake and put new gaskets on, should the gaskets get treated with some sort of RTV or other sealant or should they be bolted up dry?

Thanks!
Adam

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: Wise Old Dog on June 08, 2008, 01:03:06 PM

Dry, no RTV on any intake system. It will kill your O2 sensor.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: adam12hicks on June 08, 2008, 04:22:37 PM

Ok thanks!  I wonder why someone used this red rubbery goodge (that's not a word) on the metal gaskets... so the throttle body to intake manifold is separated by a single dry metal gasket?

Thanks again for the response!

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: nicknikolovski on June 08, 2008, 07:06:06 PM

It could be rubber grease, not sure why its on there.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: tjts1 on June 08, 2008, 10:25:04 PM

Quote from: Wise Old Dog;50802

Dry, no RTV on any intake system. It will kill your O2 sensor.

Unless you use "O2 sensor safe RTV". I just used RTV on the TB gasket, between the lower and upper halves of the manifold and at the head. No gaskets = no problems.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: Wise Old Dog on June 09, 2008, 05:35:55 AM

I would be concerned that the silicone would squeeze out internally and create an airflow disturbance. Although it would seal better than the OEM gasket.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: tjts1 on June 09, 2008, 09:27:54 AM

Yes, you have to be very careful in how you apply it. It has to be a very thin layer, evenly spread along the outside edge of the port. You want it to squeeze out toward the outside of the port as much as possible.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: strad on June 09, 2008, 05:38:09 PM

Those metal gaskets are designed and intended to work without sealant.  They are designed to crush seal at correct torque given clean flat mating surfaces.  

If anyone besides a dealer/good independent shop has worked on your car in the past, chances are they did not know what they were doing.  That would explain the presence of sealant.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: adam12hicks on June 09, 2008, 07:03:37 PM

Yeah I'm not sure what work was done.  The car has 130k and was a 1 owner.  It still has everything factory in place, but has a new fan clutch.  The throttle body had definitely been removed though I'm not sure why it would have been.  Everything else looks OEM.

Thanks for the advice guys.   Oh and Strad, you say those are crush gaskets, but is it published anywhere how much torque should be applied to the throttle body stud nuts for them to seat properly?   (I said stud nuts... I'm going to tell my wife that's my new name.)

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: strad on June 09, 2008, 07:35:43 PM

I could not find that torque figure quickly in the E36 manual.  I seem to remember finding it though when I did all my vacuum lines.  Pretty sure I torqued those fasteners to 11 ft-lbs.

Title: Ok one more quickie - throttle body gasket - wet or dry?
Post by: adam12hicks on June 09, 2008, 07:52:53 PM

Excellent thanks for the response!