Doug_B_928

I've decided to refurbish my 79 muffler for the fun of it. So, before it gets to cold, today I decided to do an initial clean-up of the rust and paint and cut into it (outside because it's dusty). I took a couple pics and then my camera's batteries died, so I'll take some more later and post. Anyway, it appears to have a center section and then on either end it is packed with sound deadening insulation. The insulation looks kind of like steel wool, only finer. It was dusty, but the clean stuff appeared to be sort of brass in color. Questions:

1. What is this insulation? I'm hoping it's not asbestos
2. Should I replace the insulation with something, or do you think it will sound better without it?

SMTCapeCod

If the insulation is friable- degraded so it is easily broken/dusty, use extreme caution! I don't know that it would be asbestos, but any material that could release fibers and implant in lungs is not a good thing.

All subjective...but exhausts that lack any buffering/sound absorbing material can sound a bit tinny to my ear. You can buy the material from various sources, summit, Dr. Gas I think, perhaps burns stainless.

Doug_B_928

Thanks. I did an Internet search and found that asbestos had been used in mufflers, but only in paper form. I hope that's accurate. I searched the websites of the places you mentioned and nothing comes up for "muffler insulation." Any other ideas?

hacker-pschorr

http://www.burnsstainless.com/muffleraccessories.aspx

http://www.motorcycle-superstore.com...r-Packing.aspx

http://www.bristolcore.com/category_s/7.htm

http://www.yoshimura-rd.com/t-engine...lerRepack.aspx

http://www.silencerpackingmaterial.co.uk/

Doug_B_928

Awesome, thank you!

AirtekHVAC

please post pics...I am interested....the bottom of my pumpkin is rotted out....I had thought of trying to cut the bottom off and weld it back together, for the heck of it.

Mark Anderson

Ae you sure it's a factory muffler and not Ansa?

hacker-pschorr

You could always go with the kind of muffler in my 79

http://members.rennlist.com/pageauto/guess.htm

Doug_B_928

@ Hacker--that is very cool! Did you document making it? That would make a fun DIY.

@ Mark--Yep, it's the original that came with the car. Even has a build date of 01 79. I wish Ansa had made a replacement that could reasonably be mistaken for a pumpkin.

@ airtek--Here are the pics.

Before sanding

After sanding

The original muffler packing

After cutting out the back, front, top, and under tailpipe areas

It's neat to see inside the top. From the central baffle, the two pipes come off and in one direction go to cans at the top of the muffler and in the other direction become the tailpipes. The inside looks to be in very good shape, all things considered.

The base of the tailpipe area is going to be difficult. The metal is completely gone at the base between the two tailpipes. I've never welded before, so this whole project is going to be an experience for me. But I can't see how I can repair that area without cutting off the tailpipes. I'm concerned, however, about getting them back on in the correct orientation; which would seem to be very difficult. Any advice?

Ducman82

what a monster!

AirtekHVAC

Niiiice pics....makes me want to go buy a cheap HF mig, and go to town!

Doug_B_928

Go for it! If yours is in the condition mine is, you have nothing to lose.

terry gt

Got to wonder why you would patch up a old rusty muffler , when there are so many used good ones available ? Or am I wrong ? I have one that is rust free sitting colecting dust .

Doug_B_928

^^ I want the fabrication experience. Used OB mufflers are rare, at least for a 79 (I believe 78, 79, and 80 are all different).

Doug_B_928

I've made good progress on cutting out little pieces of sheet metal for patches. I could only get 22G and 16G, so am using 22G for almost everything. Nothing like starting out welding on nearly the thinnest sheet metal possible. I haven't started welding because I'm waiting for my 'money matters' rebate, which includes a helmet and gloves. Can't wait to start. In the meantime, should I spray weld through primer on the inside of the muffler to hold back rust or will the heat affect it?