Silicone Discussion

[Wreckless4thf]

Can you use silicone instead of gaskets for you intake? My ports lined up best without gaskets.

[youngengines]

I have a SB2.2 headed SBC. I used GE white 100% silicone (Wal Mart cauking tube)on my valley tray and NOTHING else. So far hasnt leaked a drop. I also use it any where else on the engine. I even used it on my headers at the head. No leaks, but the flanges are thick).

[Mike Thompson]

I use the standard tub and tile 100% clear silicone in the big tube. The only problem is over time it will wick up the oil. I guess because its not automotive grade. It has no problem lasting a season so thats good enough for me.

[Wreckless4thf]

Originally Posted by Wreckless4thf

Can you use silicone instead of gaskets for your intake? My ports lined up best without gaskets.

Nobody does this???

[Mike Thompson]

Originally Posted by Wreckless4thf

Nobody does this???

Fuel is not friendly to silicone.

[Bad News]

In no particular order.......

All of these are glazing quality silicone hence they are not cheap but are all available in a 10.2 oz caulk tube . Most are also available in colors.

GE General glazing SCS 1000 or 1200 clr, silver (aluminium),black,white, bronze.
Acetic cure type. Has some oil resistance, heat capability and uv stability. good stuff

GE Silglaze Neutral cure black
GE silpruf Neutral cure black
Dow Corning 795 neutral cure black
The above 3 are like the right stuff

Check into glazier supply co,s CRLaurence and Sommer and Maca ind. Also some plastic supply houses. They will stock smaller quanities like 12 and 24 tube boxes.
The clear and such available at the home centers has no oil resistance , heat threshold ,or uv stabilitiy.

Hope this helps.

[Chris Uratchko]

Originally Posted by Wreckless4thf

Nobody does this???

When I have to, I have done and still do this... no issues on a drag race engine.... don't know about on the street. There are OEM's out there that also don't use any gaskets on much of anything including the intake manfiolds..... just food for thought.

[hotrod2111]

Ok So nobody has stated the best way to preserve a tube after opening. The best way i've found is about a 3 " piece of duct tape wrapped tightly around the spout, then squeeze a little to fill the void in the tape.

[FastZ28s]

Originally Posted by hotrod2111

Ok So nobody has stated the best way to preserve a tube after opening. The best way i've found is about a 3 " piece of duct tape wrapped tightly around the spout, then squeeze a little to fill the void in the tape.

A large wire nut (a size that fits tightly) works great!

[FastZ28s]

Originally Posted by Chris Uratchko

When I have to, I have done and still do this... no issues on a drag race engine.... don't know about on the street. There are OEM's out there that also don't use any gaskets on much of anything including the intake manfiolds..... just food for thought.

We have done this too.
Also the comment about fuel not being friendly with silicone is true for the types that don't contain additives to make them fuel resistant, but there are plenty of high-quality silicones that will stand up to being exposed to air-fuel mixtures, and are therefore made to be used on intakes, and etc.... and there are some sealants made for aircraft work that behave like silicone, but are actually made up of other ingredients that are used on "wet wings" and therefore are constantly exposed to fuel without any problems since this is what they are designed for...

[Barry_R]

Motorcraft TA-31
gray silicone for 6.5/7.3 diesel service. Dries almost plastic in consistancy. Best stuff I've ever used for end seals & such. Fuel & oil don't seem to touch it. Comes in a caulk tube from the Ford dealer.

[ROB]

Originally Posted by Barry_R

Motorcraft TA-31
gray silicone for 6.5/7.3 diesel service. Dries almost plastic in consistancy. Best stuff I've ever used for end seals & such. Fuel & oil don't seem to touch it. Comes in a caulk tube from the Ford dealer.

This is good stuff but should be used sparingly on thin sheet aluminum parts. I've used this product a lot and have never been dissatisfied with it.

[69Cobra]

One more vote for Valco here! Good people, family owned and the shit works! Last I heard Hendrick Motorsports was using Valco's products.

[BigS1975]

3rd vote for motorcraft TA 31.I get a tube for every rearend job or diff. service.So I can say that shit is stock piled in my tool box.

[racer99]

Originally Posted by gieser

International grey silicone will seal damn near anything, just don't plan on taking it apart without cutting it off, international made a special razor sharp cutting tool that you hit with a hammer to cut the oil pans off, but it does come in a big tube and seals better then anything else ive used, just my .02 cents.

Same as Ford TA31 made for 7.3s.
It is grey,lasts forever and comes in a
caulking gun tube.