1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

RB Exhaust Question

Thread Tools
 
Search this Thread
 
Old 07-04-07, 09:08 AM
  #1  
B6T
ERTW

Thread Starter
iTrader: (2)
 
B6T's Avatar
 
Join Date: Nov 2004
Location: Waterloo, Ontario
Posts: 880
Likes: 0
Received 0 Likes on 0 Posts
RB Exhaust Question

I've got a full RB exhaust system on my GSL-SE. It's the single pipe system that uses the OEM mid-pipe. When I installed it, I used high-temp silicone on all gaskets just to ensure everything seals nicely and stays quiet.

The problem is that it sounds like there is a slight leak, but I cannot find a leak at any of the flanges (can't feel exhaust gases exiting at the flange). I think it might just be the exhaust pulsing in the header, but because it sounds exactly like an exhaust leak, I'm confused. Does anyone else have this exhaust system and has noticed this?

Thanks!
Old 07-04-07, 10:45 AM
  #2  
Senior Member

 
AdamAnt's Avatar
 
Join Date: Jul 2002
Location: Burlington, Ontario
Posts: 517
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by B6T
I've got a full RB exhaust system on my GSL-SE. It's the single pipe system that uses the OEM mid-pipe. When I installed it, I used high-temp silicone on all gaskets just to ensure everything seals nicely and stays quiet.

The problem is that it sounds like there is a slight leak, but I cannot find a leak at any of the flanges (can't feel exhaust gases exiting at the flange). I think it might just be the exhaust pulsing in the header, but because it sounds exactly like an exhaust leak, I'm confused. Does anyone else have this exhaust system and has noticed this?

Thanks!
Any chance you still have the air pump hooked up? That could make the noise. I had a GSL with that set up years ago and it did not make any noise.

Adam
Old 07-04-07, 02:14 PM
  #3  
Lapping = Fapping

iTrader: (13)
 
Jeff20B's Avatar
 
Join Date: Aug 2001
Location: Near Seattle
Posts: 15,725
Received 83 Likes on 76 Posts
Are those gaskets supposed to be installed dry? I think they are. It's most likely to leak at the header flange where it bolts to the presilencer as that is the hotest part. You'd think the engine flange is the hottest but it's not. Remember you have the cooling system nearby.
Old 07-04-07, 02:24 PM
  #4  
Famous Taillights

iTrader: (3)
 
FirebirdSlayer666's Avatar
 
Join Date: Oct 2005
Location: Hagerstown, MD
Posts: 3,443
Likes: 0
Received 1 Like on 1 Post
I'd go back and double check your bolts on the header as well, they can have a tendancy to back thread themselves loose
Old 07-04-07, 02:41 PM
  #5  
Lapping = Fapping

iTrader: (13)
 
Jeff20B's Avatar
 
Join Date: Aug 2001
Location: Near Seattle
Posts: 15,725
Received 83 Likes on 76 Posts
Good idea. They don't actually unscrew themselves. What happens is the gasket relaxes a bit. So double check all fasteners.
Old 07-04-07, 02:53 PM
  #6  
Rotoholic Moderookie

iTrader: (4)
 
vipernicus42's Avatar
 
Join Date: May 2002
Location: Ottawa, Soviet Canuckistan
Posts: 5,962
Received 32 Likes on 25 Posts
High temp silicon could NOT withstand the 1800-2000F that your rotary's exhaust puts out. Those gaskets are meant to be installed dry (or one exhaust shop told me that you could soak it in water for a half hour before installation which would make the little white dots on the gasket expand before installation, though I don't know if that's a good idea).

In any case, your leak may be caused by the fact that you used silicon and now it has burned or melted away, leaving a gap for exhaust gas to escape.

If I were you, I'd just bite the bullet, buy a new set of gaskets and install them dry, or have a shop install them since they have impact wrenches and torches that you don't have, which would make it easier to remove the old gaskets and give a better seal on the new ones.

But that's just my opinion. You might get by just by tightening the hell out of it as it is now.

Jon
Old 07-04-07, 05:17 PM
  #7  
Lapping = Fapping

iTrader: (13)
 
Jeff20B's Avatar
 
Join Date: Aug 2001
Location: Near Seattle
Posts: 15,725
Received 83 Likes on 76 Posts
One more thing. Once a gasket is compromised, the white stuff between the metal pieces burns out and allows exhaust to leak. Best to install them dry and avoid the hassle.
Old 07-04-07, 11:06 PM
  #8  
B6T
ERTW

Thread Starter
iTrader: (2)
 
B6T's Avatar
 
Join Date: Nov 2004
Location: Waterloo, Ontario
Posts: 880
Likes: 0
Received 0 Likes on 0 Posts
Thanks for the suggestions guys. I know the header gasket isn't leaking, but it's possible that one of the gaskets is leaking because I didn't use new ones when I installed the exhaust (bought it used). Then again, I can't feel any leaks around the joints. Any other thoughts?
Old 07-05-07, 07:45 AM
  #9  
Bubble Gum's Good

iTrader: (1)
 
glewsRx's Avatar
 
Join Date: May 2005
Location: Norfolk, VA
Posts: 625
Likes: 0
Received 0 Likes on 0 Posts
Yeah, your exhaust is leaking and the above suggestions are sufficient.
Old 07-05-07, 09:37 AM
  #10  
RX for fun

iTrader: (13)
 
Siraniko's Avatar
 
Join Date: Aug 2001
Location: Socal
Posts: 15,926
Likes: 0
Received 22 Likes on 19 Posts
Originally Posted by vipernicus42
High temp silicon could NOT withstand the 1800-2000F that your rotary's exhaust puts out. Those gaskets are meant to be installed dry (or one exhaust shop told me that you could soak it in water for a half hour before installation which would make the little white dots on the gasket expand before installation, though I don't know if that's a good idea).

Jon
I disagree with the above. I always add a dab of silicone on the exhaust gaskets to ensure that it doesnt leak particularly on the 13-B header which came with many styles. In fact, with my set-ups, I use a 12-A header gasket which is cut in half.
Old 07-05-07, 10:42 AM
  #11  
My 7 is my girlfriend.

iTrader: (5)
 
orion84gsl's Avatar
 
Join Date: Feb 2006
Location: London, Ontario, Canada
Posts: 3,162
Likes: 0
Received 1 Like on 1 Post
My header seems to be making the same noise, however no leaks were found, so I assume its just the pulses hitting the header. It's actually louder at the header than at the muffler. I've emailed Jim Langer at RB about this, but still waiting on a response.
Old 07-05-07, 11:16 AM
  #12  
Have RX-7, will restore


iTrader: (91)
 
mazdaverx713b's Avatar
 
Join Date: Oct 2003
Location: Ohio
Posts: 21,750
Received 1,062 Likes on 899 Posts
i completely agree with installing the gaskets dry. its a must! however, if your header were a smidge loose for long periods of running time, it MAY have warped the flange bolting to the engine or the flange bolting to the presilencer. this is a long shot since its pretty difficult to warp a flange, but it does happen and its another avenue to check once you reinstall your gaskets dry if the problem is not corrected.

Last edited by mazdaverx713b; 07-05-07 at 11:37 AM.
Old 07-05-07, 11:25 AM
  #13  
Lapping = Fapping

iTrader: (13)
 
Jeff20B's Avatar
 
Join Date: Aug 2001
Location: Near Seattle
Posts: 15,725
Received 83 Likes on 76 Posts
Did you check the torque on the nuts yet?
Old 07-05-07, 02:39 PM
  #14  
Senior Member

iTrader: (1)
 
sevens4me's Avatar
 
Join Date: May 2006
Location: State College, PA
Posts: 459
Likes: 0
Received 0 Likes on 0 Posts
I also installed that system on my GSL-SE very recently and I also used a very high temp silicone gasket sealer on all my new gaskets. It is VERY quiet and definitely not leaking, I haven't retightened anything yet, either. It has only been on for slightly less than 1000 miles, though.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Skeese
Adaptronic Engine Mgmt - AUS
65
03-28-17 03:30 PM
msilvia
3rd Generation Specific (1993-2002)
28
04-14-16 12:58 PM
12abridgeport
1st Generation Specific (1979-1985)
2
08-17-15 06:28 PM



Quick Reply: RB Exhaust Question



All times are GMT -5. The time now is 02:12 PM.