| My Muffler Install... [message #305165] |
Mon, 08 August 2016 16:26  |
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thainglo
Messages: 132
Registered: March 2015
Location: Iowa
Karma: 2
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One project that bumped itself to the top of the list after a lot of backfiring due to vapor lock was replacing the two mufflers. The passenger side, which previously had a few small perforations, burst all around. Driver side held up better but was badly bent and damaged.
This is from the rear looking forward. Wish I had gotten one from the front looking back as that is where the real fun took place.
Not a heat shield - that is the top of the muffler...
Never having tackled exhaust work, I was a little apprehensive, but I got a couple of great tips from Jon Roche and grabbed my sawzall and cutoff wheel and went to work. The sawzall is the right tool to remove the mufflers from each end of the pipes, then the cutoff wheel can make a nice shallow cut to remove the outer muffler pipe from the inner exhaust section. I made a cut on each side and the pieces fell right off. I was a little worried that the pieces would be frozen together from decades of hot/cold cycles, but came apart a lot easier than I expected.
The driver side muffler had been replaced at some point, I'm guessing. However, the markings on the passenger side top of the muffler makes me wonder if it could be the original.
It only took about an hour or so to get both mufflers off, with me not working with blinding speed. Got called away at this point to pick up a sick child, but was able to tackle later in the afternoon.
I used a flapper wheel to really clean up each end of the exhaust pipes so the new mufflers would slide on as easy as possible. Once clean, I unbolted the rear part of the exhaust from the frame to give me some extra room to squeeze the mufflers in.
When I was ready, coated the outer and inner parts of the pipes that would be meshing together with this exhaust sealing compound. Figured it would help the pieces slide together and maybe provide the sealing benefit as well.
These were the mufflers and clamps I used:
I was impressed with the clamps. One bolt fought me, had to take it down to the workbench and work a tap through the threads, then everything went together easy.
Assembly and cleanup was another couple hours, with me taking my time and enjoying the quiet. Total cost from Summit was $104 with free shipping. Once the mufflers rot away, I may go with the single pipe and muffler in the rear, but this was a fair amount to spend right now.
Soundwise, I don't notice much different at the rear of the tailpipe or in the cabin, but I only fired it up for a few minutes to check for leaks. Certainly nothing outrageous, probably the most sound just because the mufflers are located where they are (likely the best reason for the rear muffler setup!).
All told, happy with the results and parts used. A few more photos in the album, but mainly just more of the destroyed mufflers. I forgot to take one of the finished product while I had the coach jacked up in the air, and now not much to see of the finished product.
Matt Sladek
1976 Eleganza II
Coralville, IA
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| Re: My Muffler Install... [message #305199 is a reply to message #305165] |
Tue, 09 August 2016 09:43  |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Senior Member |
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Sure looks like a GM OEM muffler. Most were dual wall construction so long after the internals were eaten away by combustion byproducts, the case held together pretty well even surviving "minor" backfire events. Take a look at the skin where exploded and see if two layers.
John Lebetski
Woodstock, IL
77 Eleganza II
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