Chasing Exhaust Leaks, This is maddening, so many issues. |
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Chasing Exhaust Leaks, This is maddening, so many issues. |
ctc911ctc |
Apr 7 2020, 02:56 PM
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#1
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Senior Member Group: Members Posts: 892 Joined: 9-June 18 From: boston Member No.: 22,206 Region Association: North East States |
All,
'74 914, 2L, original engine - about 20K miles I started a new thread because the ones I could find did not address this issue. Perhaps it is me???? Last month I purchased new gaskets (thanks Mark @914R) and annealed them as per instructions. Used super glue to stick them in place. Mounted the heat exchanger/manifold and locked them in with around 20lbs of torque. Copper goo on the nuts, etc. When I started the car it was the sound of my youth - smooth, strong,,,,,,ahh After a few days the sound changed, using a rubber tube held to my ear I found exhaust leaks in the junction to the muffler (used new gaskets, alum sandwiched ones). Here are the leaks Copper Gasket Leaks Seems as if the nuts were not tight enough. I made certain that the edge of the pipes were square and both on the same plane. Questions as to the copper gaskets: 1. Seems that one was not seated concentrically with the pipe, that exhaust was leaking from day one - is there a method to square this or center it? 2. the other gasket it seems did not get seated at all, so it seems as if it was concentric just not tight enough????? Now the aluminum Gaskets I really tightened the bolts, I have ordered new gaskets and am brushing smooth the flanges which were both kind of cruddy, any advice as to installing these? THANK YOU TEENERS! |
TheCabinetmaker |
Apr 9 2020, 06:49 AM
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#2
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Torque is 14lbs. "About 20"? Did you use a torque wrench? Never saw a setting that said about. Overtightening will cause the ears to bend and possibly crack, and can strip the threads in the head. Torque to 10, then 12, then 14. Torque slowly, and "feel" for anything that doesn't seem right. Install muffler, but just snug before torqueing he's. I had a Bursch muffler that just would not seal. The flanges were thin, and warped. Had my welder make new flanges from ¼" steel. 4 years and no leaks yet. Won't buy another Bursch! The last one l bought still had wet paint out of the box, and you could see where they beat a cavity in it to accommodate the misplaced pipes. It cracked at that point.
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ctc911ctc |
Apr 9 2020, 08:07 AM
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#3
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Senior Member Group: Members Posts: 892 Joined: 9-June 18 From: boston Member No.: 22,206 Region Association: North East States |
Excellent Guidance!
(IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/pray.gif) I used a 1/4 inch drive. I hand tightened them to a good strong but not teeth-gnashing torque. New lovely copper nuts, synch, tighten, tighten, round and round while watching the copper gaskets making certain they were proud on all sides of the pipe. Putting the final touches on today - will post results. CTC911CTC Torque is 14lbs. "About 20"? Did you use a torque wrench? Never saw a setting that said about. Overtightening will cause the ears to bend and possibly crack, and can strip the threads in the head. Torque to 10, then 12, then 14. Torque slowly, and "feel" for anything that doesn't seem right. Install muffler, but just snug before torqueing he's. I had a Bursch muffler that just would not seal. The flanges were thin, and warped. Had my welder make new flanges from ¼" steel. 4 years and no leaks yet. Won't buy another Bursch! The last one l bought still had wet paint out of the box, and you could see where they beat a cavity in it to accommodate the misplaced pipes. It cracked at that point. |
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