Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
> Exhaust tape?, tape the joints of my Eurorace...
VaccaRabite
post Apr 14 2009, 08:07 AM
Post #1


En Garde!
**********

Group: Admin
Posts: 13,553
Joined: 15-December 03
From: Dallastown, PA
Member No.: 1,435
Region Association: MidAtlantic Region



My carbs are popping on decel. It could be timing, but I bet that my Eurorace headers are leaking from the collector. I know I can see exhaust coming from it at idle.

I think I remember seeing some sort of aluminum tape that you could put on exhaust pipes to seal a leak. I thought that might be an easy way to seal up those joins after I have the pipes ceramic coated.

Anyone know anything about it? What have others done to stop the collector leaks on their EuroRace headers?

Zach
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cap'n Krusty
post Apr 14 2009, 08:38 AM
Post #2


Cap'n Krusty
**********

Group: Members
Posts: 10,794
Joined: 24-June 04
From: Santa Maria, CA
Member No.: 2,246
Region Association: Central California



QUOTE(Vacca Rabite @ Apr 14 2009, 07:07 AM) *

My carbs are popping on decel. It could be timing, but I bet that my Eurorace headers are leaking from the collector. I know I can see exhaust coming from it at idle.

I think I remember seeing some sort of aluminum tape that you could put on exhaust pipes to seal a leak. I thought that might be an easy way to seal up those joins after I have the pipes ceramic coated.

Anyone know anything about it? What have others done to stop the collector leaks on their EuroRace headers?

Zach


"Could be timing"? 'Splain that, please. I see it pop up all the time in these discussions, but have never, in nearly 40 years of schooling and wrenching, seen any documentation to support this statement. The Cap'n
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
ConeDodger
post Apr 14 2009, 08:53 AM
Post #3


Apex killer!
***************

Group: Members
Posts: 23,757
Joined: 31-December 04
From: Tahoe Area
Member No.: 3,380
Region Association: Northern California



QUOTE(Vacca Rabite @ Apr 14 2009, 06:07 AM) *

My carbs are popping on decel. It could be timing, but I bet that my Eurorace headers are leaking from the collector. I know I can see exhaust coming from it at idle.

I think I remember seeing some sort of aluminum tape that you could put on exhaust pipes to seal a leak. I thought that might be an easy way to seal up those joins after I have the pipes ceramic coated.

Anyone know anything about it? What have others done to stop the collector leaks on their EuroRace headers?

Zach


Red RTV Silicone. Sensor safe in my case...
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
VaccaRabite
post Apr 14 2009, 09:28 AM
Post #4


En Garde!
**********

Group: Admin
Posts: 13,553
Joined: 15-December 03
From: Dallastown, PA
Member No.: 1,435
Region Association: MidAtlantic Region



QUOTE(Cap'n Krusty @ Apr 14 2009, 09:38 AM) *

QUOTE(Vacca Rabite @ Apr 14 2009, 07:07 AM) *

My carbs are popping on decel. It could be timing, but I bet that my Eurorace headers are leaking from the collector. I know I can see exhaust coming from it at idle.

I think I remember seeing some sort of aluminum tape that you could put on exhaust pipes to seal a leak. I thought that might be an easy way to seal up those joins after I have the pipes ceramic coated.

Anyone know anything about it? What have others done to stop the collector leaks on their EuroRace headers?

Zach


"Could be timing"? 'Splain that, please. I see it pop up all the time in these discussions, but have never, in nearly 40 years of schooling and wrenching, seen any documentation to support this statement. The Cap'n


http://www.youtube.com/watch?v=PbnVnjfgM8A

T4, backfire due to being 180 out of time (surrounded by World members).

I dunno about when time is close enough to be running. But another member recently had a thread about a running engine that was backfiring stop when he got the timing right.

But, as I said, I think my issue is exhaust leaks from the header collector, and not timing.

Zach
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
jimkelly
post Apr 14 2009, 10:25 AM
Post #5


Delaware USA
****

Group: Members
Posts: 4,969
Joined: 5-August 04
From: Delaware, USA
Member No.: 2,460
Region Association: MidAtlantic Region



a fine gentleman like myself always learns something when hanging out with these gear heads.

lesson learned that day - fire out the carbs is bad : )


Attached image(s)
Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
SirAndy
post Apr 14 2009, 10:33 AM
Post #6


Resident German
*************************

Group: Admin
Posts: 41,815
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



QUOTE(Vacca Rabite @ Apr 14 2009, 08:28 AM) *

T4, backfire due to being 180 out of time (surrounded by World members).

I dunno about when time is close enough to be running. But another member recently had a thread about a running engine that was backfiring stop when he got the timing right.

But none of those were backfiring on decel as you stated in your first post.


A otherwise good running engine that backfires on decel will most likely have an exhaust leak ...
(IMG:style_emoticons/default/shades.gif) Andy
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cap'n Krusty
post Apr 14 2009, 02:35 PM
Post #7


Cap'n Krusty
**********

Group: Members
Posts: 10,794
Joined: 24-June 04
From: Santa Maria, CA
Member No.: 2,246
Region Association: Central California



Let's talk about this. Your car runs, right? I thought so. The evidence you give for reaching the conclusion that timing will cause backfiring consists of a video of an engine backfiring with the timing 180 degrees out. Note that it it never starts, and that the backfiring is through the intake, not the exhaust. An engine 180 out won't run. Nor will one 90 degrees off. Maybe even 45 degrees. Even at 5 or 10 degrees, timing won't cause backfiring in our exhaust systems. Exhaust backfires in T4s tuned for the street is usually either a serious lack of exhaust back pressure or a leak, allowing fresh air to be drawn into the system. Backfires through the carbs on a running engine are generally either intake leaks, badly worn carbs, or failure to properly adjust the carbs and the linkage.

The Cap'n
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
r_towle
post Apr 14 2009, 04:53 PM
Post #8


Custom Member
***************

Group: Members
Posts: 24,624
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States



If your motor is backfiring from the carbs...you are running too lean.
Look for leaks at the manifolds, loose bolts at the carb base...that sort of stuff. re-tighten every single bolt/nut on the intake. Also clean your idle jets...one clogged jet will make it backfire up the carb.

If its backfiring from the exhaust at decel...well fix the damn leak.
Red RTV can be used...yup. I would take a closer look at the joints and come up with a better mechanical solution...not a fan of sealants in the exhaust setup....just a long term repair and maintenance issue that will never go away.

Rich
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Chris Pincetich
post Apr 14 2009, 08:09 PM
Post #9


B-)
****

Group: Members
Posts: 2,082
Joined: 3-October 05
From: Point Reyes Station, CA
Member No.: 4,907
Region Association: Northern California



I have fiberglass exhaust wrap around mine. I doubt it plugs any leaks, but the header was a little less than tight at the collector and the wrap really tightens it all up as well as saving my cables from the heat. The header is ceramic coated, so I am hoping all the bad issues with rust found doing this (exhaust wrap) will not be a problem. After a year part of the wrap is worn, so I may unwrap it soon to check/maybe replace/clean out the crap it is likely collecting. My cables are doing great! (IMG:style_emoticons/default/beerchug.gif)
Use that red RTV on the stub pipes (IMG:style_emoticons/default/wink.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
SLITS
post Apr 15 2009, 06:59 AM
Post #10


"This Utah shit is HARSH!"
**********

Group: Benefactors
Posts: 13,602
Joined: 22-February 04
From: SoCal Mountains ...
Member No.: 1,696
Region Association: None



Exhaust wrap is cool ... for a race car. The retained heat causes the metal to crystalize and crack or turn to dust in your hand. Just be prepared to spend more money.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
underthetire
post Apr 15 2009, 09:03 AM
Post #11


914 Guru
*****

Group: Members
Posts: 5,062
Joined: 7-October 08
From: Brentwood
Member No.: 9,623
Region Association: Northern California



A good gasket and High temp RTV. The copper stuff works well, but not sensor safe. The red works almost as good, but is sensor safe. The aluminum tape works like crap. Used to use that when I was a kid. Burns right through.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
VaccaRabite
post Apr 15 2009, 09:50 AM
Post #12


En Garde!
**********

Group: Admin
Posts: 13,553
Joined: 15-December 03
From: Dallastown, PA
Member No.: 1,435
Region Association: MidAtlantic Region



Okay, so if I understand Capt and Rich, since I am popping up through the carbs, it is not an exhaust leak, but an induction leak.

The carbs I have are fresh rebuilt, but I will clean the idle jets again.

The phenolic gasket between the head and the manifold has a thin smear of RVT on it, and the nuts are tight, so it is unlikely that it leaks there.

I can try putting a little rvt on the gasket between the carb and the manifold, and tighten the nuts again.

The linkage being off a bit is a possibility. it is close right now, but I do not think that it is exact.

I'll likely hit people up for tuning help at the MidEngine Invasion to get it running right.

Zach
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 26th September 2024 - 05:30 PM