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Replacing exhaust system [message #303975] Fri, 22 July 2016 11:27 Go to next message
SCFire1 is currently offline  SCFire1   United States
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My exhaust system is shot ('78 Royale)....from the headers back. Need to replace the exhaust pipes, the mufflers and the tailpipe. Does anyone know of a good shop in SC, NC, or GA? I know Jim Bounds will do it but, Lord have mercy, that's a long way! Any help would be appreciated.

John Mitchell Cross Anchor, SC (upstate SC) 1978 Royale Owned by my cousin in California for 30 years....purchased by a gentleman in the Atlanta area 7 years ago...finding my cousin's GMC by accident....Priceless!
Re: Replacing exhaust system [message #303978 is a reply to message #303975] Fri, 22 July 2016 11:36 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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You can buy cut and bent to fit pipes from Applied, but any competent muffler shop should be able to fabricate a system to your spec. I use an old grayhaired fart on the Atlanta highway in Gainesville. He did my ratrod toad, the 370 Plymouth and several others. Fabs to fit, and he will happily put Smitty mufflers on anything old enough to not have a cat on it. And anything you want behind the cat if there is one. He told me it's supposed to be left stock in front of the converter according to the EPA. This is of course a non-issue on the GMC.
Make sure whoever does the job puts heat shields between the tanks and the pipe and replaces the donuts where the pipe goes through the frame crossmembers.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: Replacing exhaust system [message #304019 is a reply to message #303978] Sat, 23 July 2016 05:37 Go to previous messageGo to next message
Loffen is currently offline  Loffen   Norway
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I am building mine from pre bent tubing, might be a little easier for me as I will have headers and weld everything together

http://i1126.photobucket.com/albums/l610/Espen_Heitmann/1973%20Sequoia/IMG_2905_zpsz16by7n0.jpg

http://i1126.photobucket.com/albums/l610/Espen_Heitmann/1973%20Sequoia/IMG_2959_zpsrefwfvzj.jpg

http://i1126.photobucket.com/albums/l610/Espen_Heitmann/1973%20Sequoia/IMG_2958_zpskot0isfr.jpg

http://i1126.photobucket.com/albums/l610/Espen_Heitmann/1973%20Sequoia/IMG_3021_zpsjwv60eni.jpg


1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green, And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel in Norway
Re: Replacing exhaust system [message #304020 is a reply to message #304019] Sat, 23 July 2016 05:40 Go to previous messageGo to next message
Loffen is currently offline  Loffen   Norway
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Did almost forget my other GMC, Golby had a original system made for me, pretty much bolt on

1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green, And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel in Norway
Re: Replacing exhaust system [message #304021 is a reply to message #304020] Sat, 23 July 2016 06:52 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Shop n Knoxville, TN did my complete system from exhaust manifolds to rear of coach for $425. Works just like GM designed it. Only about 200 miles from you. But, really any real muffler shop should be able to fabricate one. They will need a 4 post lift. Be tough to do on your back, but I went that way on my first coach.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: Replacing exhaust system [message #304024 is a reply to message #304020] Sat, 23 July 2016 09:02 Go to previous messageGo to next message
mrgmc3 is currently offline  mrgmc3   United States
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Loffen wrote on Sat, 23 July 2016 05:40
Did almost forget my other GMC, Golby had a original system made for me, pretty much bolt on


Frame off is certainly the easy way to install a new system!
I am curious about your decision to run mufflers in series rather than parallel.


Chris Geils - Twin Cities / W Wa 1978 26' Kingsley w/ very few mods; PD9040, aux trans cooler, one repaint in stock colors, R134a, Al rad, Alcoas, 54k mi
Re: [GMCnet] Replacing exhaust system [message #304028 is a reply to message #304024] Sat, 23 July 2016 10:42 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Our system is a bolt on unit made for us by Jerry Jarden.
He made and sold these kits back in 1990 .
All mandrel bent, 2 1/2" SS mufflers that join and become 3" all the way to
the tail pipe.
We supply in all SS or the pipes in Aluminized steel.

On Sat, Jul 23, 2016 at 7:02 AM, Chris Geils
wrote:

> Loffen wrote on Sat, 23 July 2016 05:40
>> Did almost forget my other GMC, Golby had a original system made for me,
> pretty much bolt on
>
>
> Frame off is certainly the easy way to install a new system!
> I am curious about your decision to run mufflers in series rather than
> parallel.
> --
> Chris Geils - Twin Cities
> 1978 26' Kingsley w/ very few mods; Headers, Progressive Dynamics 9040,
> aux trans cooler, one repaint in stock colors, R134a, Al rad, 49k mi
>
> _______________________________________________
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Replacing exhaust system [message #304030 is a reply to message #303975] Sat, 23 July 2016 11:13 Go to previous messageGo to next message
GeorgeRud is currently offline  GeorgeRud   United States
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I installed Jim's two muffler system when I first purchased my GMC. Using ramps and jackstands, I was able to install it by myself with hand tools. It's a high quality, well engineered system.

George Rudawsky
Chicago, IL
75 Palm Beach
Re: [GMCnet] Replacing exhaust system [message #304072 is a reply to message #304030] Sat, 23 July 2016 21:24 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Lot of times the 3" high temp silicon rubber we caap "Muffler Bearings "
are missing, but we stock them as they hold the pipe from vibrating against
the frame.

On Sat, Jul 23, 2016 at 9:13 AM, George Rudawsky
wrote:

> I installed Jim's two muffler system when I first purchased my GMC. Using
> ramps and jackstands, I was able to install it by myself with hand tools.
> It's a high quality, well engineered system.
> --
> George Rudawsky
> Chicago, IL
> 75 Palm Beach
>
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> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: Replacing exhaust system [message #304082 is a reply to message #304024] Sun, 24 July 2016 02:22 Go to previous messageGo to next message
Loffen is currently offline  Loffen   Norway
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mrgmc3 wrote on Sat, 23 July 2016 16:02
Loffen wrote on Sat, 23 July 2016 05:40
Did almost forget my other GMC, Golby had a original system made for me, pretty much bolt on


Frame off is certainly the easy way to install a new system!
I am curious about your decision to run mufflers in series rather than parallel.


Two reasons, I wanted flexible joints after the headers to take away vibrations since it is a pretty tight fit through the frame with 3" tubing.
I would need some kind of Y pipe so why not give it some functionality ? and the second muffler with opposite in and out give me space enough to use mandrel bent 90 degree tubing and it is much quieter than a straight through muffler, yes and I like quiet in a RV, still have room for a resonator in the rear if it makes to much noise.


1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green, And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel in Norway
Re: [GMCnet] Replacing exhaust system [message #304111 is a reply to message #304082] Sun, 24 July 2016 10:45 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
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I really like your layout and workmanship on your new exhaust system, especially the use of the flexible joints. I do see some issues that might come back and bite you in the butt. I noticed that you are welding most of the joints and that can make for a very tight system without leaks, but it make it very difficult to repair sections when they fail. It does appear that your are not using SS tubing or mufflers. Not really a problem, but your system life is going to be much shorter than an all SS system. The exhaust systems on our coaches generate a fair amount of condensate at first startup that collects in the mufflers and down the tail pipe to the rear and until the entire system heats up and boils it out and it is fairly corrosive. Look at your mufflers and if they have a weep hole that should be installed down, not all mufflers do come with a weep hole. Look at the puddle out back if you idle your coach before you go down the road. It takes a number of minutes under load to get the entire exhaust system up to temp to remove the condensate that has collected in the system. That is also why that it is not a good idea to startup and run your coach while in storage during the cold weather (winter), the condensate never gets evaporated and the engine oil never gets hot enough to get rid of condensate or hydrocarbon blow by, it takes a load to get the heat up and a short trip would do that. Dick Paterson has said that is the worst thing that you can do for your motor, just let it sit all winter and start it in the spring. For those of you that live in warmer climates it still be an issue if you don’t get the temps up to load temps.

I would have probably made the layout in smaller sections put together by SS band clamps. When I first started using them about 15 years ago I didn’t tighten them enough and did have some leakage and movement issues. When I bought some exhaust parts for our first coach Jim K said to torque them to 65 FT/LBS and they will not leak or move, haven’t had any issues since with the system moving or leaking. I also use a muffler sealant paste and smear it on the inside of the band clamps for additional sealing before tightening. They come in 2 1/4 to larger than 3” and are available here in the US and most autoparts store and from most of our major GMC parts suppliers. Where you live I don’t know how hard it would be to purchase.

https://www.napaonline.com/napa/en/p/BK_7335621/BK_7335621
and
http://www.jegs.com/p/JEGS-Performance-Products/JEGS-Preformed-Stainless-Steel-Exhaust-Band-Clamps/753274/10002/-1
or
http://tinyurl.com/7y3nl2h
As a few examples

Muffler sealant
http://www.jegs.com/pt/Muffler+Cement/4294955186
and

or
http://tinyurl.com/glx9m3c

I think that Jim K made a comment about the use or replacement of the”Muffler Bearings” which is a very old car joke! But really they hold the exhaust pipe going down the side of the coach to the rear to prevent vibration and noise. Without them you're going to have a really difficult time preventing the long exhaust pipe from hitting the frame, but again that is your choice.

Muffler bearings!
http://www.appliedgmc.com/prod.itml/icOid/1180

JR Wright
GMC Great Laker MHC
GMC Eastern States Charter Member
GMCGL Tech Editor
GMCMI
78 GMC Buskirk 30’ Stretch
1975 GMC Avion (Under Reconstruction)
Michigan

> On Jul 24, 2016, at 3:22 AM, Espen Heitmann wrote:
>
> Two reasons, I wanted flexible joints after the headers to take away vibrations since it is a pretty tight fit through the frame with 3" tubing.
> I would need some kind of Y pipe so why not give it some functionality ? and the second muffler with opposite in and out give me space enough to use
> mandrel bent 90 degree tubing and it is much quieter than a straight through muffler, yes and I like quiet in a RV, still have room for a resonator in
> the rear if it makes to much noise.
> --
> 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Mean Green Machine,
> And just sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel
> in Norway
>


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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: [GMCnet] Replacing exhaust system [message #304115 is a reply to message #304111] Sun, 24 July 2016 11:22 Go to previous messageGo to next message
Loffen is currently offline  Loffen   Norway
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The first muffler is stainless and the rest is pretty thick steel tubing, should last for 5 years or more without any problems and cheap to replace, I wanted it welded as I am sick and tired of exhaust system shaking it self to bits, not to worried about taking it apart either,posted a picture of a similar tube cutter as the one I have below.
And I do have the muffler bearings, no problem Smile

Sure condense can be a problem and I could drill a small drip hole, but the total cost of the system is under $ 600 with stainless steel headers from Manny and a couple of hours work

http://i1126.photobucket.com/albums/l610/Espen_Heitmann/1973%20Sequoia/20-329_xl_1_zpspwl18fyf.jpg


1973 23' # 1848 Sky Blue Glacier called Baby Blue and a 1973 26'-3 # 1460 Parrot green Seqouia Known as the Big Green, And sold my 1973 26'-2 # 581 White Canyon lands under the name Dobbelt trøbbel in Norway
Re: [GMCnet] Replacing exhaust system [message #304116 is a reply to message #304115] Sun, 24 July 2016 11:26 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Why does that tool look like it's assembled backwards?

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Replacing exhaust system [message #304117 is a reply to message #304116] Sun, 24 July 2016 11:27 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Maybe it's just an optical delusion... Laughing

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Replacing exhaust system [message #304135 is a reply to message #304117] Sun, 24 July 2016 15:27 Go to previous messageGo to next message
hal kading is currently offline  hal kading   United States
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It cuts from the inside out! Cool

Hal Kading 78 Buskirk 502 Las Cruces NM
Re: Replacing exhaust system [message #304167 is a reply to message #303975] Sun, 24 July 2016 19:31 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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I like the muffler as a Y like GM did on the Tahoes and Suburbans Interested to see how the muffler into muffler theory sounds and performs. Nice work.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Replacing exhaust system [message #304170 is a reply to message #304116] Sun, 24 July 2016 20:40 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Because it's designed to cut tubing from the inside working out? :-)

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Terry
Sent: Monday, July 25, 2016 2:27 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Replacing exhaust system

Why does that tool look like it's assembled backwards?
--
Terry Kelpien


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Replacing exhaust system [message #304171 is a reply to message #304135] Sun, 24 July 2016 20:40 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Sorry Hal I hadn't read your response or as they say; "great err warped minds think alike!"

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Hal Kading
Sent: Monday, July 25, 2016 6:28 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Replacing exhaust system

It cuts from the inside out! 8)

Hal Kading 78 Buskirk 502 Las Cruces NM

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Replacing exhaust system [message #304176 is a reply to message #304170] Sun, 24 July 2016 21:43 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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USAussie wrote on Sun, 24 July 2016 20:40
Because it's designed to cut tubing from the inside working out? Smile

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426


If it looks up side down and backwards, it has to the the AUSSIE VERSION of the tool or it came from Harbor Freight.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Replacing exhaust system [message #304183 is a reply to message #304176] Sun, 24 July 2016 23:52 Go to previous messageGo to previous message
Bullitthead is currently offline  Bullitthead   United States
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You really have to admire Espen's work ethic and quality of workmanship on that hillside far,far away from virtually all the rest of the GMC world here in the U.S. Smile And doing it outdoors, as well...Nice work!

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
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