3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

better exhaust gaskets.

Thread Tools
 
Search this Thread
 
Old 06-03-08, 10:55 PM
  #1  
It's finally reliable

Thread Starter
iTrader: (18)
 
MOBEONER's Avatar
 
Join Date: May 2004
Location: NEW YORK CITY
Posts: 3,511
Received 9 Likes on 7 Posts
better exhaust gaskets.

Has anyone tried different methods to installing exhaust system gaskets that actually don’t leak?? I was thinking for installing 1/8 of an inch soft aluminum instead of your typical gaskets.
Old 06-03-08, 11:03 PM
  #2  
Brappable.

iTrader: (6)
 
RLaoFD's Avatar
 
Join Date: May 2005
Location: Bay Area
Posts: 1,384
Received 4 Likes on 3 Posts
If you use silicone gasket sealant with new gaskets, you should never get a leak.
Old 06-03-08, 11:17 PM
  #3  
It's finally reliable

Thread Starter
iTrader: (18)
 
MOBEONER's Avatar
 
Join Date: May 2004
Location: NEW YORK CITY
Posts: 3,511
Received 9 Likes on 7 Posts
It’s an exhaust system it will burn any sealing compound right out, I have tried those types of sealants and they only last a day or 2
Old 06-03-08, 11:41 PM
  #4  
Brappable.

iTrader: (6)
 
RLaoFD's Avatar
 
Join Date: May 2005
Location: Bay Area
Posts: 1,384
Received 4 Likes on 3 Posts
The right kind of Permatex exhaust gasket sealant will be able to take a lot of heat.
Old 06-03-08, 11:54 PM
  #5  
Rotary Enthusiast

 
Eggie's Avatar
 
Join Date: Jan 2002
Location: 15143
Posts: 859
Likes: 0
Received 0 Likes on 0 Posts
I doubt aluminum would handle the heat for long. Copper would be a better choice.
Old 06-03-08, 11:54 PM
  #6  
Senior Member

iTrader: (10)
 
red_dragon's Avatar
 
Join Date: May 2006
Location: Bay Area, CA
Posts: 619
Received 1 Like on 1 Post
which permatex sealant is the "right kind"? I'm trying to deal with my exhaust leak too.
Old 06-04-08, 12:22 AM
  #7  
Senior Member

iTrader: (10)
 
red_dragon's Avatar
 
Join Date: May 2006
Location: Bay Area, CA
Posts: 619
Received 1 Like on 1 Post
hmm ok so i found 2 kinds. The first one is copper hi-temp spray a gasket with temp range from -50 to 500F. The other kind is non-hardening Hylomar HPF with temp range -60 to 600F. Any idea which one might be better?
Old 06-04-08, 01:21 AM
  #8  
Banned. I got OWNED!!!
 
njstreetrx7's Avatar
 
Join Date: Sep 2003
Location: new jersey
Posts: 2,030
Likes: 0
Received 0 Likes on 0 Posts
I Use Copper Works Very Well
Old 06-04-08, 02:06 AM
  #9  
Archdandy

iTrader: (1)
 
hsitko's Avatar
 
Join Date: Mar 2006
Location: Predominantly educated metropolitan area
Posts: 550
Likes: 0
Received 3 Likes on 2 Posts
Or...new gaskets, and good exhaust nuts? Are you guys just being retarded? This isnt some kind of joke right?
Old 06-04-08, 02:42 AM
  #10  
Jeremy

iTrader: (1)
 
blue94FD's Avatar
 
Join Date: May 2006
Location: Hollywood, FL
Posts: 263
Likes: 0
Received 0 Likes on 0 Posts
http://permatex.com/products/Automot...sket_Maker.htm

I use this on everything. never had a leak, never blown out or burned up. perfect seal years later.
Old 06-04-08, 02:42 AM
  #11  
Senior Member

iTrader: (10)
 
red_dragon's Avatar
 
Join Date: May 2006
Location: Bay Area, CA
Posts: 619
Received 1 Like on 1 Post
lol well i mean some of us might have the misfortune of buying something like...say a bonez HF cat which has flanges that happen to not be flat (yay). Even with new gaskets I still have a fat exhaust leak.
Old 06-04-08, 02:43 AM
  #12  
Senior Member

iTrader: (10)
 
red_dragon's Avatar
 
Join Date: May 2006
Location: Bay Area, CA
Posts: 619
Received 1 Like on 1 Post
nvrmind, question answered
Old 06-04-08, 02:44 AM
  #13  
Brappable.

iTrader: (6)
 
RLaoFD's Avatar
 
Join Date: May 2005
Location: Bay Area
Posts: 1,384
Received 4 Likes on 3 Posts
Originally Posted by red_dragon
hmm ok so i found 2 kinds. The first one is copper hi-temp spray a gasket with temp range from -50 to 500F. The other kind is non-hardening Hylomar HPF with temp range -60 to 600F. Any idea which one might be better?
The Hylomar will work well with the situation you're describing with your HF cat.
Old 06-04-08, 05:12 AM
  #14  
Moderator

iTrader: (7)
 
dgeesaman's Avatar
 
Join Date: May 2002
Location: Fort Kickass
Posts: 12,302
Received 16 Likes on 15 Posts
I've tried the various high-temp silicones. They all went to toast for me.

I've used OEM. They work but they're expensive and don't conform at all to slightly warped flanged. Stainless exhaust parts are really nice, but they don't tend to be very flat. Doubling the OEM gasket sometimes works.

Recently I'm using two new options: 1) embossed solid copper gasket by SCE gasket at my 3" 2-bolt sections. 2) compressible graphite for the downpipe gasket. I got the graphite piece from Pineapple Racing. Rob says he usually doesn't run these on stock exhausts due to the backpressure blowing them out, but I have an aftermarket downpipe and cat-back installed so I'm not quite that bad. So far so good.

Both of these new options are working well, can take up a lot of warpage, and don't cost an OEM fortune.

Last edited by dgeesaman; 06-04-08 at 11:54 AM.
Old 06-04-08, 07:32 AM
  #15  
Racecar - Formula 2000

 
DaveW's Avatar
 
Join Date: Sep 2002
Location: Bath, OH
Posts: 3,850
Received 277 Likes on 198 Posts
Remflex Exhaust Gaskets

https://www.rx7club.com/showthread.p...hlight=remflex

Dave
Old 06-04-08, 11:53 AM
  #16  
Moderator

iTrader: (7)
 
dgeesaman's Avatar
 
Join Date: May 2002
Location: Fort Kickass
Posts: 12,302
Received 16 Likes on 15 Posts
^ This is the type of material I got from Pineapple.

Dave
Old 06-04-08, 02:33 PM
  #17  
Rotary Enthusiast

 
Eggie's Avatar
 
Join Date: Jan 2002
Location: 15143
Posts: 859
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by dgeesaman
2) compressible graphite for the downpipe gasket.
<snip>
So far so good.
How many miles do you have on this?
Old 06-04-08, 02:52 PM
  #18  
silver ghost

iTrader: (11)
 
G's 3rd Gen's Avatar
 
Join Date: Sep 2003
Location: Home of the Rolex 24
Posts: 3,061
Likes: 0
Received 5 Likes on 5 Posts
I think your prblem may lie w/ the flanges not gaskets. After time the expanding and contracting from the heat will cause the exhaust flanges to warp. The gaskests usually still seal until you take the exhaust apart and put it back together. I have had success by heating the flanges to glowing red hot and banging them w/ a hammer on a flat surface to straighten them to true. Let them cool an rehang them and it should seal fine. ( I have left the downpipe on and torched the flange right on the car. With a couple of whacks you can pull ithis off as well. ) G
Old 06-04-08, 03:00 PM
  #19  
Ooooooh, custom.

 
Rotary Noob's Avatar
 
Join Date: Oct 2006
Location: Corona, CA
Posts: 618
Likes: 0
Received 0 Likes on 0 Posts
I have a 2nd gen...but the issues are still the same.

Every time ive tried using ultra copper...it burns out right where the leak is. Stays fine on the outside of the flange, but where it needs to be, it doesnt do a damn thing.

I havent tried copper, but V bands work great. Sometimes the bolts warp though...which I suppose is why they sell just the band clamp...

What I did to fix mine is just weld everything together. I know that if its all welded then it wont leak, period. Its a temporary fix, on the stock (all 90lbs of it) exhaust. Itll get changed soon...but I need to pass smog.

I would recommend staying away from sealants though.

Heating the flange sounds like a good idea though...I might have to try that next time.
Old 06-04-08, 03:20 PM
  #20  
All Spooled Up

iTrader: (7)
 
badddrx7's Avatar
 
Join Date: Nov 2001
Location: Ironton,ohio
Posts: 2,752
Likes: 0
Received 3 Likes on 3 Posts
I do not know of ANY sealants that will hold up to the heat and stress produced on an exhaust system - period. And I wouldn't believe in any if anyone produced one. However I do believe in flat exhaust flange surfaces, new metal impregnated gaskets and some nickle-eze anti sieze lube for the bolts. This will hold and is what I run.


Later
Old 06-04-08, 05:01 PM
  #21  
Moderator

iTrader: (7)
 
dgeesaman's Avatar
 
Join Date: May 2002
Location: Fort Kickass
Posts: 12,302
Received 16 Likes on 15 Posts
Originally Posted by Eggie
How many miles do you have on this?
About 100.

That's why you haven't heard me making any particular endorsement yet. I still have my stock gasket, so if it blows out I guess I need to spend a couple more hours changing the gasket again.

Also, as Tom has said ^, no sealant I've ever tried has even come close to working. Even at the joint in the cat-back, which should be the coolest joint in the exhaust, the 600F fancy Permatex Copper Silicone sealant burns up in days.

Dave
Old 06-05-08, 11:52 AM
  #22  
TANSTAFL

iTrader: (13)
 
alexdimen's Avatar
 
Join Date: Oct 2003
Location: Richmond, Va.
Posts: 3,770
Received 123 Likes on 82 Posts
All of you guys probably have warped flanges. Those 2-bolt flanges love to warp from overtightening and aftermarket gaskets that let the ears bend.

I've had luck heating the flanges on my FC with an oxyacetalene torch, then whacking them on the ears (put a stack of nuts over studs to protect them or remove the studs) to bend them back the other way a little. My FC is finally leak free after doing this.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jeff20B
1st Generation Specific (1979-1985)
73
09-16-18 07:16 PM
Ian_D
New Member RX-7 Technical
6
09-06-15 10:38 PM
doritoloco
New Member RX-7 Technical
7
09-05-15 12:41 PM



Quick Reply: better exhaust gaskets.



All times are GMT -5. The time now is 03:15 AM.