Uh-Oh.......Exhaust leak in header area
Well, I think there may be two of us.
I, too, have an exhaust leak. I tried to use a boroscope today to get a look at the header installed ( mainly looking at the area BA found the crack ) and while I don't consider it conclusive I believe I have a similar problem. I'll have to get a better look this weekend, as this is my daily driver. I've already spoken to Loren about this and I'm sure we will be taken care of. I'll keep everyone posted.
Oh, I was #19 on the initial buy.
I, too, have an exhaust leak. I tried to use a boroscope today to get a look at the header installed ( mainly looking at the area BA found the crack ) and while I don't consider it conclusive I believe I have a similar problem. I'll have to get a better look this weekend, as this is my daily driver. I've already spoken to Loren about this and I'm sure we will be taken care of. I'll keep everyone posted.Oh, I was #19 on the initial buy.
EV ftw!!!
Joined: Nov 2002
Posts: 9,066
Likes: 622
From: Lake Ontario
Well, I think there may be two of us. I, too, have an exhaust leak. I tried to use a boroscope today to get a look at the header installed ( mainly looking at the area BA found the crack ) and while I don't consider it conclusive I believe I have a similar problem. I'll have to get a better look this weekend, as this is my daily driver. I've already spoken to Loren about this and I'm sure we will be taken care of. I'll keep everyone posted.
Oh, I was #19 on the initial buy.
I, too, have an exhaust leak. I tried to use a boroscope today to get a look at the header installed ( mainly looking at the area BA found the crack ) and while I don't consider it conclusive I believe I have a similar problem. I'll have to get a better look this weekend, as this is my daily driver. I've already spoken to Loren about this and I'm sure we will be taken care of. I'll keep everyone posted.Oh, I was #19 on the initial buy.
Please keep us posted as I was kinda looking forward to doing this mod early next year.....
Lead Lap
Joined: Jul 2003
Posts: 719
Likes: 0
From: Torrance, California
These are coated both inside and out, correct?
Since it happened during a race day, i'd say that the weld failed because of heavy thermal cycling occuring in between runs. There may be some pre-existing stress on that particular runner causing the heat to excacerbate an issue that may not be readily apparent on cars that are driven mildly.
If TeeLex experienced problems with that same runner, the design will definitely need to be checked or reinforced.
edit: How are the condition of your motormounts?
Since it happened during a race day, i'd say that the weld failed because of heavy thermal cycling occuring in between runs. There may be some pre-existing stress on that particular runner causing the heat to excacerbate an issue that may not be readily apparent on cars that are driven mildly.
If TeeLex experienced problems with that same runner, the design will definitely need to be checked or reinforced.
edit: How are the condition of your motormounts?
Last edited by MikeFD3S; Sep 14, 2006 at 11:03 AM. Reason: forgot something
These are coated both inside and out, correct?
Since it happened during a race day, i'd say that the weld failed because of heavy thermal cycling occuring in between runs. There may be some pre-existing stress on that particular runner causing the heat to excacerbate an issue that may not be readily apparent on cars that are driven mildly.
If TeeLex experienced problems with that same runner, the design will definitely need to be checked or reinforced.
Since it happened during a race day, i'd say that the weld failed because of heavy thermal cycling occuring in between runs. There may be some pre-existing stress on that particular runner causing the heat to excacerbate an issue that may not be readily apparent on cars that are driven mildly.
If TeeLex experienced problems with that same runner, the design will definitely need to be checked or reinforced.
Well said. I agree with each point.
.
That is definitely an unusual failure and is not what I expected from the construction and the initial report. I left a voice mail for Loren at S&S requesting a return call and of course hope that this is an isolated occurance.
I can say that every effort was made to create a strong reliable header. Anyone who has seen one of these 1st hand can attest that the materials and design look very strong. There has been some worries about the way the primary pipes are welded to the head flange but this is a common and proven header construction procedure. The person that had their headers re-welded prior to installation (can't remember who off the top of my head) actually was concerned about the catalyst flange on the redesigned header. This flange was originally welded 360 degrees on the outside but thanks to BA the design was changed for catalyst insert lip clearance. With this change the same joint is now welded 360 degrees on the inside.
BA, I feel for you. You have made a big contribution in this header journey and it just doesn't seem fair for you to be the one. Thanks for all you have done.
I can say that every effort was made to create a strong reliable header. Anyone who has seen one of these 1st hand can attest that the materials and design look very strong. There has been some worries about the way the primary pipes are welded to the head flange but this is a common and proven header construction procedure. The person that had their headers re-welded prior to installation (can't remember who off the top of my head) actually was concerned about the catalyst flange on the redesigned header. This flange was originally welded 360 degrees on the outside but thanks to BA the design was changed for catalyst insert lip clearance. With this change the same joint is now welded 360 degrees on the inside.
BA, I feel for you. You have made a big contribution in this header journey and it just doesn't seem fair for you to be the one. Thanks for all you have done.
Thanks for the kind words John. I do appreciate it.
I agree that these are strong, nicely welded headers. Nine months and mine still look great, and it's my daily driver here in Salty/Snowy/Rainy Ohio.
TEELEX - dude, it's cool that you have a boroscope!
I hate to hear that you may the same issue though. Major bummer! 
Check out the next post!
The Other Side
more good stuff. Hell, I don't mind keeping this header like this!
Putting the thing back on now because I leave tomorrow morning for a trip to Pigeon Forge TN. (car show)
Putting the thing back on now because I leave tomorrow morning for a trip to Pigeon Forge TN. (car show)
Lexus Fanatic
Joined: Aug 2004
Posts: 6,947
Likes: 4
From: Florida
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BA,
Is that the passenger side?
Actually I have access to a boroscope at my place of work. It is kinda cool to have some toys available for things like this.
I will make sure that I fluorescent penetrant inspect the header for hairline cracks after I un-install -or- if I get a new replacement, that one will get the FPI, too.
Hopefully this is not a design problem - I might be able to talk Loren into letting me do a 'failure analysis' on the header if I confirm cracking this weekend. I will be able to tell if the weld was penetrated properly -or- not.
Is that the passenger side?
Actually I have access to a boroscope at my place of work. It is kinda cool to have some toys available for things like this.
I will make sure that I fluorescent penetrant inspect the header for hairline cracks after I un-install -or- if I get a new replacement, that one will get the FPI, too.Hopefully this is not a design problem - I might be able to talk Loren into letting me do a 'failure analysis' on the header if I confirm cracking this weekend. I will be able to tell if the weld was penetrated properly -or- not.
It is indeed the passenger side TeeLex. On mine, visually, it did not look like the weld got deep enough between the pipes. I think my 1/4 mile stuff (heat cycling) exacerbated the problem.
Last edited by BA_GS400; Sep 14, 2006 at 07:16 PM.
Well after a closer look with good lighting and a small mirror one things for sure - I don't have any big cracks.
I have one small indication that I'm not sure if its real or not. In any case I do not have large cracks like BA. In fact the headers look pretty much like the day I installed them. Looks like I'll be checking out the cat to custom mid-pipe flanges for the suspected leak. So before I go any further with the header, I'm gonna make sure it's not the cat to mid-pipe flange 'seal' this weekend.
I hope the repair works out for you BA, cause we both know it's not a lot of fun changing headers on GS4 cars.
I have one small indication that I'm not sure if its real or not. In any case I do not have large cracks like BA. In fact the headers look pretty much like the day I installed them. Looks like I'll be checking out the cat to custom mid-pipe flanges for the suspected leak. So before I go any further with the header, I'm gonna make sure it's not the cat to mid-pipe flange 'seal' this weekend. I hope the repair works out for you BA, cause we both know it's not a lot of fun changing headers on GS4 cars.
WHEW! Got those pesky lights to go away after disconnecting the + battery cable for about an hour. Wow am I relieved! I didn't want to pay the Lexus stealership to give me a code and charge me for it. (which they would)
Road trip is ON!
Oh yeah, the exhaust leak is gone of course.
Road trip is ON!
Oh yeah, the exhaust leak is gone of course.
Lexus Champion
Joined: Feb 2001
Posts: 3,124
Likes: 32
From: Texas
Nice repair BA! It looks like you are darn quick with the R&R. How long did it take not having to mess with the heat shields? I had a long conversation with Loren today and he was VERY interested in getting this resolved. He said he shipped out a header to someone today... TeeLex? He will be reviewing BA's repair and may incorporate additional welding or bracing depending on outcome. He said he just ordered flanges for 20 more sets.
BTW, TeeLex, I am impressed by your resources. I look forward to your input. Hopefully yours will just be a gasket issue.
I also agree, those headers look pretty darn good for the wear.
BTW, TeeLex, I am impressed by your resources. I look forward to your input. Hopefully yours will just be a gasket issue.
I also agree, those headers look pretty darn good for the wear.
