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O-ring manifold sealing with square section

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O-ring manifold sealing with square section


Post by panster » Fri Oct 14, 2005 2:24 am

Has anyone ever seen any intake O rings with a SQUARE section? It seems to me that they might do a better job, as they sit in a channel shape recess! Just wondered,

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Re: O-ring manifold sealing with square section


Post by caschnd1 » Fri Oct 14, 2005 5:41 am

I've only seen them with a square cross section after they've been installed for a while and you remove them. I think the idea with the round cross section is that it crushes down to fit the square groove and makes a seal by forming to it.


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Re: O-ring manifold sealing with square section


Post by bibs » Sat Dec 17, 2005 3:54 am

has anyone ever tried using teflon tape around the indent where the o-rings sit in first....then slip the o-rings in place.....seems to me it would make a great seal!!! I,m going to try it on my pan.

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Re: O-ring manifold sealing with square section


Post by Cotten » Sat Dec 17, 2005 4:08 am


Been there tried that ferget it.

Teflon extrudes, meaning it deforms and squeezes away from where you want it as vibrations and the cyclic expansion and contraction from heat moves things around constantly.

If there was something better than just a clean and dry assembly, then the Factory would be selling it. (With a licensed product logo and a hefty pricetag!)

The best way to avoid manifold leaks is to test while installing, by putting ~15 psi of airpressure on on it, and squirting dilute dishsoap all around the clamps. When the bubbles stop, you've found the sweetspot, and must then make the carb align to it without bind.

Good luck!

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