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  #21  
Old 03-22-2013, 08:42 AM
BigJohn BigJohn is offline
 
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Location: Gloversville, NY
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Thank you for the good advice, and getting this thread back on track. I will be pulling the muffler off this coming week and will report on what I find.

Lee, do you think I should replace those original springs after only 140 hours? What about earlier suggestion to bend the tabs for more tension?
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  #22  
Old 03-22-2013, 01:44 PM
Dave12 Dave12 is offline
 
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It looks like your springs have been exposed to a fair bit of heat.
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  #23  
Old 03-22-2013, 03:40 PM
Mich48041 Mich48041 is offline
 
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Location: Riley TWP MI
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Default Testing extension spirngs

Connect one end of an old spring and a new spring together, then pull the opposite ends apart. The weakest spring will expand the most.
A scale can measure the force required to stretch a spring a certain distance. The spring could apply upward force on a weight sitting on a bathroom scale. Or a fish scale could stretch the spring. Each spring should be stretched an equal amount to get an accurate comparison.
Joe Gores
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  #24  
Old 03-23-2013, 12:00 AM
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jetmech jetmech is offline
 
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Location: Fairfield, CA
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[Lee, do you think I should replace those original springs after only 140 hours? What about earlier suggestion to bend the tabs for more tension?[/quote]

Aloha-those springs look heat soaked they are cheap to replace..on the tabs be easy they can crack if you torque them to much(done it)
Lee
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  #25  
Old 03-23-2013, 08:39 AM
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DonFromTX DonFromTX is offline
 
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IF heat softened the springs and this was the only problem, you would see gaps between the coils, which does not seem to be the case. Is it possible that the tabs were softened and released the tension? Of course we don't know how they looked when installed either.
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  #26  
Old 03-23-2013, 11:27 AM
RFSchaller RFSchaller is offline
 
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Location: Phoenix, AZ
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When I connected the oil return line I moved the muffler against spring pressure and created the Sam problem. Reseating the joint fixed it.
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  #27  
Old 04-05-2013, 07:23 PM
BigJohn BigJohn is offline
 
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My new S/S springs came today and since my airplane is still torn down for the inspection I dove right in. Removed the muffler and all four pipes. Cleaned all the joints and used the anti-seize paste liberally. Reassembled with nuts just snugged. Moved the muffler around to get it properly centered and torqued down the nuts.

Now for the interesting part. Most of the springs appeared to have very little tension on them, and it didn't take much force to pull the muff outward to loosen the joints. Didn't look right to me. Checked all the springs, and there was not even enough tension on most of them to create a gap between the coils big enough to insert a piece of paper into. VERY CAREFULLY (envisioning ordering new pipes) bent most of the tabs using a big screwdriver as a lever. Adjusted until all springs had enough tension to pass the paper test.

Musing about why my springs were so loose. Did I get a muffler that was welded up wrong? Couldn't be bad springs because new ones were the same as old. At any rate, I think my problem is solved. Time will tell.

I suggest all builders check spring tension when they first assemble their exhaust systems. If you can't pass a slip of paper between the coils investigate further. Call Van's Support before taking any action.
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  #28  
Old 05-08-2013, 04:07 AM
crashley crashley is offline
 
Join Date: Jun 2009
Location: hazelwood north vic
Posts: 158
Default exhaust

hi i had the same leak. a local exhaust shop tried to expand the pipe a little because he said there was too much clearance, but, it was too small to fit in his expander so I just cleaned the joints and bent the spring mounts to apply more tension. I also replaced a spring that had nearly worn through the leak is still there but not as bad

and with the cowlings the more you remove and replace them the easier it becomes and it helps to adjust the clocking of the oil pipes to make the oil filter just slide into place also after 285 hours the hinge pins slide in and out very easily
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  #29  
Old 10-24-2017, 10:21 AM
todehnal todehnal is offline
 
Join Date: Jan 2005
Location: Kentucky Lakes area in KY
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Quote:
Originally Posted by BigJohn View Post
My new S/S springs came today and since my airplane is still torn down for the inspection I dove right in. Removed the muffler and all four pipes. Cleaned all the joints and used the anti-seize paste liberally. Reassembled with nuts just snugged. Moved the muffler around to get it properly centered and torqued down the nuts.

Now for the interesting part. Most of the springs appeared to have very little tension on them, and it didn't take much force to pull the muff outward to loosen the joints. Didn't look right to me. Checked all the springs, and there was not even enough tension on most of them to create a gap between the coils big enough to insert a piece of paper into. VERY CAREFULLY (envisioning ordering new pipes) bent most of the tabs using a big screwdriver as a lever. Adjusted until all springs had enough tension to pass the paper test.

Musing about why my springs were so loose. Did I get a muffler that was welded up wrong? Couldn't be bad springs because new ones were the same as old. At any rate, I think my problem is solved. Time will tell.

I suggest all builders check spring tension when they first assemble their exhaust systems. If you can't pass a slip of paper between the coils investigate further. Call Van's Support before taking any action.
Hey John,

As I remember it, you replaced your muffler springs with stainless steel. I assume that you got them from Spruce. How satisfied are you with them? Any more leaks, or broken springs, and did you add the high temp RTV?

I'm noticing some blow-by evidence and I need to re-seal with that copper paste. I don't have any broken springs, but they do appear to have lost some tension. Tom
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  #30  
Old 10-24-2017, 10:54 AM
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Piper J3 Piper J3 is offline
 
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I'll jump in here... I installed SS exhaust springs from Spruce 100 hours ago. They were loose during the install so I re-bent the welded attachment bales to stretch the springs and add preload. Added benefit is springs are now spaced further away from exhaust tubing. I used high-temp RTV to pack the inside of each spring. Good fix...
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