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Exhaust System Advice Please? [message #200821] Wed, 06 March 2013 20:26 Go to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

On our trip to Triangle-T Ranch (135 mile round trip) in January, I noticed the motorhome exhaust getting progressively louder. The next trip for gas, it got even louder. I checked under the hatch and all the gaskets on the exhaust manifolds were good, so I checked the underside. The right muffler was not looking good, so I ordered a new exhaust system from Jim K.

By the time we got home from the February GMCSJ rally (just across town) it was really bad. The right muffler was completely blown out. So, I was relieved to sse several boxes and some 3" pipe on the front porch when we got home.

Last weekend, I installed the new system, a 3" system with the two front mounted mufflers (Magnaflow) and aluminized pipe. I figured I didn't need the SS in our climate,even though we intend to travel in places where we will most likely see more rain than we get here. The aluminized system comes from Jim K with 'U' clamps. I got the old system out and the new system in, in about 9 - 10 hours.

My old system had a hanger on the tailpipe that Jim advised was not original equipment. He said that it was not needed if the clamps are tight enough. I decided to add a bracket and a hanger anyway, just to make the tailpipe a bit more stable.

My question is, would it be advisable to go through the whole system with my MIG welder and put a small weld on each of the joints. I don't really relish the thought of laying on my back and welding overhead, but will do it if it needs to be done (I have a leather welding 'shirt'). My thinking, right now, is that it is not necessary. The system is stable the way it is, with the clamps, and I will weld the bracket to the tail pipe, stabilizing it even further.

Overall, I am very happy with Jim's exhaust system. Other than having a little trouble fitting the mufflers to the existing head pipes, it fit together really well, and had no leaks when I was done. If I had changed to headers, I'm sure it would have gone even easier.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member

[Updated on: Thu, 07 March 2013 09:21]

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Re: [GMCnet] Exhaust System Advice Please? [message #200826 is a reply to message #200821] Wed, 06 March 2013 21:44 Go to previous messageGo to next message
jade is currently offline  jade   United States
Messages: 163
Registered: August 2009
Karma: 0
Senior Member
Carl;
What I did on both of my 3" exhaust systems was to put a short stainless
self tapping screw at each joint so if I would have to take it apart for
some reason, ie get at the bolts for the bogies, all I would have to do is
remove the screws. He sent me the band clamps that work a lot nicer than U
bolts because they don't crush the pipe.
JADE
73 23' ?? 73 26' Painted Desert
Ajo, AZ
KC7QGC

Original Message
From: "Carl Stouffer" <carljr3b@yahoo.com>
To: <gmclist@temp.gmcnet.org>
Sent: Wednesday, March 06, 2013 7:26 PM
Subject: [GMCnet] Exhaust System Advice Please?


>
>
> On our trip to Triangle-T Ranch I35 mile round trip) in January, I noticed
> the motorhome exhaust getting progressively louder. The next trip for
> gas, it got even louder. I checked under the hatch and all the gaskets on
> the exhaust manifolds were good, so I checked the underside. The right
> muffler was not looking good, so I ordered a new exhaust system from Jim
> K.
>
> By the time we got home from the February GMCSJ rally (just across town)
> it was really bad. The right muffler was completely blown out. So, I was
> relieved to sse several boxes and some 3" pipe on the front porch when we
> got home.
>
> Last weekend, I installed the new system, a 3" system with the two front
> mounted mufflers (Magnaflow) and aluminized pipe. I figured I didn't need
> the SS in our climate,even though we intend to travel in places where we
> will most likely see more rain than we get here. The aluminized system
> comes from Jim K with 'U' clamps. I got the old system out and the new
> system in, in about 9 - 10 hours.
>
> My old system had a hanger on the tailpipe that Jim advised was not
> original equipment. He said that it was not needed if the clamps are
> tight enough. I decided to add a bracket and a hanger anyway, just to
> make the tailpipe a bit more stable.
>
> My question is, would it be advisable to go through the whole system with
> my MIG welder and put a small weld on each of the joints. I don't really
> relish the thought of laying on my back and welding overhead, but will do
> it if it needs to be done (I have a leather welding 'shirt'). My
> thinking, right now, is that it is not necessary. The system is stable
> the way it is, with the clamps, and I will weld the bracket to the tail
> pipe, stabilizing it even further.
>
> Overall, I am very happy with Jim's exhaust system. Other than having a
> little trouble fitting the mufflers to the existing head pipes, it fit
> together really well, and had no leaks when I was done. If I had changed
> to headers, I'm sure it would have gone even easier.
> --
> Carl S.
> '75 ex Palm Beach
> Tucson, AZ.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


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Re: [GMCnet] Exhaust System Advice Please? [message #200828 is a reply to message #200826] Wed, 06 March 2013 22:04 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
Messages: 769
Registered: February 2013
Location: Columbia, SC
Karma: 7
Senior Member
I believe the band clamps come standard with the stainless system, He opted for the aluminized steel system which comes with u bolts.




jade wrote on Wed, 06 March 2013 21:44

Carl;
He sent me the band clamps that work a lot nicer than U
bolts because they don't crush the pipe.
JADE
73 23' ?? 73 26' Painted Desert
Ajo, AZ
KC7QGC






76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.
Re: [GMCnet] Exhaust System Advice Please? [message #200849 is a reply to message #200828] Thu, 07 March 2013 06:41 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
Band clamps are the way to go. After using them, I would never go back to the u-clamps. No distortion of the exhaust pipes, and easy to remove for repairs/replacements. U-clamps may save a little money, but you will pay for it in the end.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Exhaust System Advice Please? [message #200854 is a reply to message #200821] Thu, 07 March 2013 07:15 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Carl,

Overkill.

Regards,
Rob

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Carl Stouffer
Sent: Thursday, March 07, 2013 1:27 PM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Exhaust System Advice Please?



On our trip to Triangle-T Ranch I35 mile round trip) in January, I noticed the motorhome exhaust getting progressively louder. The
next trip for gas, it got even louder. I checked under the hatch and all the gaskets on the exhaust manifolds were good, so I
checked the underside. The right muffler was not looking good, so I ordered a new exhaust system from Jim K.

By the time we got home from the February GMCSJ rally (just across town) it was really bad. The right muffler was completely blown
out. So, I was relieved to sse several boxes and some 3" pipe on the front porch when we got home.

Last weekend, I installed the new system, a 3" system with the two front mounted mufflers (Magnaflow) and aluminized pipe. I
figured I didn't need the SS in our climate,even though we intend to travel in places where we will most likely see more rain than
we get here. The aluminized system comes from Jim K with 'U' clamps. I got the old system out and the new system in, in about 9 -
10 hours.

My old system had a hanger on the tailpipe that Jim advised was not original equipment. He said that it was not needed if the
clamps are tight enough. I decided to add a bracket and a hanger anyway, just to make the tailpipe a bit more stable.

My question is, would it be advisable to go through the whole system with my MIG welder and put a small weld on each of the joints.
I don't really relish the thought of laying on my back and welding overhead, but will do it if it needs to be done (I have a leather
welding 'shirt'). My thinking, right now, is that it is not necessary. The system is stable the way it is, with the clamps, and I
will weld the bracket to the tail pipe, stabilizing it even further.

Overall, I am very happy with Jim's exhaust system. Other than having a little trouble fitting the mufflers to the existing head
pipes, it fit together really well, and had no leaks when I was done. If I had changed to headers, I'm sure it would have gone even
easier.
--
Carl S.
'75 ex Palm Beach
Tucson, AZ.
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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] Exhaust System Advice Please? [message #200856 is a reply to message #200849] Thu, 07 March 2013 07:24 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
tphipps wrote on Thu, 07 March 2013 06:41

Band clamps are the way to go. After using them, I would never go back to the u-clamps. No distortion of the exhaust pipes, and easy to remove for repairs/replacements. U-clamps may save a little money, but you will pay for it in the end.
Tom, MS II


AMEN


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Exhaust System Advice Please? [message #200860 is a reply to message #200856] Thu, 07 March 2013 07:38 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
Messages: 3447
Registered: May 2006
Karma: 0
Senior Member
AMEN again.

On Thu, Mar 7, 2013 at 6:24 AM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> tphipps wrote on Thu, 07 March 2013 06:41
> > Band clamps are the way to go. After using them, I would never go back
> to the u-clamps. No distortion of the exhaust pipes, and easy to remove
> for repairs/replacements. U-clamps may save a little money, but you will
> pay for it in the end.
> > Tom, MS II
>
>
> AMEN
> --
> Dan & Teri Gregg
> Dexter, Mo.
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
> GMCnet mailing list
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>



--
Take care,
Steve
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Re: [GMCnet] Exhaust System Advice Please? [message #200870 is a reply to message #200860] Thu, 07 March 2013 09:01 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Okay, thanks. I will take your answers under consideration. I'm fine with the 'U' clamps. I had a band clamp on one of the joints on the old system and it didn't hold as well as the 'U' clamps. Just my experience. The point is well taken that it is easier to replace a single component using band clamps, but I don't see that happening with lifetime mufflers and aluminized pipe in my climate. There are cars on the road here from the '50s with their original exhaust systems.

At this point, I think I will weld the rear tailpipe bracket (isolated from the frame with rubber bushings) and be done with it.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Exhaust System Advice Please? [message #200968 is a reply to message #200828] Fri, 08 March 2013 00:56 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
These band clampa are so strong, that I tell our guys to use the half inch
impact to tighten the clamps .
I have run 8,000 miles on mine and the pipes have never slipped.
Jerry Jardene told me that with the headers and theMandrel bent system you
can pick up 20-25hp from the engine.
The new Aluminized pipes are far superior to ones they made 10 years ago,
so we project life to be 15 years-20.
The SS units should be good for twice that.

On Wed, Mar 6, 2013 at 8:04 PM, Joe Weir <joeweir@gmail.com> wrote:

>
>
> I believe the band clamps come standard with the stainless system, He
> opted for the aluminized steel system which comes with u bolts.
>
>
>
>
> jade wrote on Wed, 06 March 2013 21:44
> > Carl;
> > He sent me the band clamps that work a lot nicer than U
> > bolts because they don't crush the pipe.
> > JADE
> > 73 23' ?? 73 26' Painted Desert
> > Ajo, AZ
> > KC7QGC
>
>
> --
> 76 Birchaven
> Columbia, SC.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
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: [GMCnet] Exhaust System Advice Please? [message #200994 is a reply to message #200968] Fri, 08 March 2013 10:22 Go to previous messageGo to next message
John Wright is currently offline  John Wright   United States
Messages: 118
Registered: September 2008
Karma: 0
Senior Member
Jim is correct that you need to torque the band clamps as stated on the packaging. They should be torqued to 50 to 60 ft/lbs at a min. I also use a muffler paste when I put them together.

J.R. Wright
30' Buskirk Stretch
Michigan
On Location in Florida

On Mar 8, 2013, at 1:56 AM, Jim Kanomata <jimkanomata@gmail.com> wrote:

> These band clampa are so strong, that I tell our guys to use the half inch
> impact to tighten the clamps .
> I have run 8,000 miles on mine and the pipes have never slipped.
> Jerry Jardene told me that with the headers and theMandrel bent system you
> can pick up 20-25hp from the engine.
> The new Aluminized pipes are far superior to ones they made 10 years ago,
> so we project life to be 15 years-20.
> The SS units should be good for twice that.
>
> On Wed, Mar 6, 2013 at 8:04 PM, Joe Weir <joeweir@gmail.com> wrote:
>
>>
>>
>> I believe the band clamps come standard with the stainless system, He
>> opted for the aluminized steel system which comes with u bolts.
>>
>>
>>
>>
>> jade wrote on Wed, 06 March 2013 21:44
>>> Carl;
>>> He sent me the band clamps that work a lot nicer than U
>>> bolts because they don't crush the pipe.
>>> JADE
>>> 73 23' ?? 73 26' Painted Desert
>>> Ajo, AZ
>>> KC7QGC
>>
>>
>> --
>> 76 Birchaven
>> Columbia, SC.
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] Exhaust System Advice Please? [message #201013 is a reply to message #200994] Fri, 08 March 2013 12:55 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

I went ahead and put a bracket on the tailpipe. It is almost identical to the one some PO had added to my old exhaust system. I thought it was a good idea. Here are some pics:

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Exhaust System Advice Please? [message #201015 is a reply to message #201013] Fri, 08 March 2013 13:00 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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Registered: November 2005
Karma: 2
Senior Member
Carl S. wrote on Fri, 08 March 2013 12:55

I went ahead and put a bracket on the tailpipe. It is almost identical to the one some PO had added to my old exhaust system. I thought it was a good idea. Here are some pics:

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html


Carl,

Any idea how much the exhaust system expands and moves towards the rear of the coach? I ask because I thought that was the reason GMC went to the silicone rings with slip pipe.

Dennis


Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: [GMCnet] Exhaust System Advice Please? [message #201031 is a reply to message #201015] Fri, 08 March 2013 16:05 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Dennis S wrote on Fri, 08 March 2013 12:00



Carl,

Any idea how much the exhaust system expands and moves towards the rear of the coach? I ask because I thought that was the reason GMC went to the silicone rings with slip pipe.

Dennis



Don't know Dennis. I hadn't even thought about it. I will have to monitor it and see what happens. There should be some 'slip' in all the other joints. Maybe that will be enough to take care of the expansion.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Exhaust System Advice Please? [message #201043 is a reply to message #201031] Fri, 08 March 2013 17:30 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Carl,

When JimB's mate down in Orlando replaced the tail pipe on Double Trouble he used a hanger that had a middle section which was a
large rubber donut.

http://tinyurl.com/afeo4y3

Regards,
Rob M.

-----Original Message-----
From: Carl Stouffer

Don't know Dennis. I hadn't even thought about it. I will have to monitor it and see what happens. There should be some 'slip' in
all the other joints. Maybe that will be enough to take care of the expansion.
--
Carl

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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] Exhaust System Advice Please? [message #201048 is a reply to message #201031] Fri, 08 March 2013 18:17 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
When monitoring that tailpipe expansion, watch for unexpected
interferences. A few years back, my nearly-new black water tank began to
drip. Examination showed that one end of a U-clamp on the tailpipe,
normally about 1" forward of the forward right corner of the black water
was moving to the rear enough to wear a hole in the tank. The movement was
too far to be blamed solely on thermal expansion, so other fore/aft
movement of the drivetrain &/or exhaust system had to contribute. Simply
turning the clamp so there could be no contact removed the hazard.
Silicone is still on the wound.

Ken H.

On Fri, Mar 8, 2013 at 5:05 PM, Carl Stouffer wrote:

>
> Dennis S wrote on Fri, 08 March 2013 12:00

> Any idea how much the exhaust system expands and moves towards the rear
> of the coach? I ask because I thought that was the reason GMC went to the
> silicone rings with slip pipe.


>
> Don't know Dennis. I hadn't even thought about it. I will have to
> monitor it and see what happens. There should be some 'slip' in all the
> other joints. Maybe that will be enough to take care of the expansion.
> --
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Exhaust System Advice Please? [message #201117 is a reply to message #200821] Sat, 09 March 2013 11:54 Go to previous messageGo to next message
An87ttype is currently offline  An87ttype   United States
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Registered: September 2012
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Senior Member
Hi Carl, i looked at some of your other pics of the snakes and bobcats. If you ask me, I think it's way to scary to live in AZ. I don't know how you do it!

1975 Eleganza II Hudson Valley NY
Re: Exhaust System Advice Please? [message #201119 is a reply to message #201117] Sat, 09 March 2013 12:43 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
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Senior Member

An87ttype wrote on Sat, 09 March 2013 10:54

Hi Carl, i looked at some of your other pics of the snakes and bobcats. If you ask me, I think it's way to scary to live in AZ. I don't know how you do it!



It's an adventure! Laughing Sure beats rain all summer and snow all winter. Smile


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Exhaust System Advice Please? [message #201121 is a reply to message #201048] Sat, 09 March 2013 12:46 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Ken Henderson wrote on Fri, 08 March 2013 17:17

When monitoring that tailpipe expansion, watch for unexpected
interferences. A few years back, my nearly-new black water tank began to
drip. Examination showed that one end of a U-clamp on the tailpipe,
normally about 1" forward of the forward right corner of the black water
was moving to the rear enough to wear a hole in the tank. The movement was
too far to be blamed solely on thermal expansion, so other fore/aft
movement of the drivetrain &/or exhaust system had to contribute. Simply
turning the clamp so there could be no contact removed the hazard.
Silicone is still on the wound.

Ken H.

On Fri, Mar 8, 2013 at 5:05 PM, Carl Stouffer wrote:

>
> Dennis S wrote on Fri, 08 March 2013 12:00

> Any idea how much the exhaust system expands and moves towards the rear
> of the coach? I ask because I thought that was the reason GMC went to the
> silicone rings with slip pipe.


>
> Don't know Dennis. I hadn't even thought about it. I will have to
> monitor it and see what happens. There should be some 'slip' in all the
> other joints. Maybe that will be enough to take care of the expansion.
> --
>
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Thanks for the advice, Ken. I'll take another look at that and check for interference.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Exhaust System Advice Please? [message #202571 is a reply to message #201015] Sun, 24 March 2013 17:47 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Dennis S wrote on Fri, 08 March 2013 12:00

Carl S. wrote on Fri, 08 March 2013 12:55

I went ahead and put a bracket on the tailpipe. It is almost identical to the one some PO had added to my old exhaust system. I thought it was a good idea. Here are some pics:

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html


Carl,

Any idea how much the exhaust system expands and moves towards the rear of the coach? I ask because I thought that was the reason GMC went to the silicone rings with slip pipe.

Dennis



Dennis (and anyone else who is interested),

In order to allow for any possible expansion on the length of the exhaust pipe, I loosened the bolt on my "custom" rear tailpipe hanger, and double nutted it. I wanted to see if the pipes were expanding, in length, and figured the angle of the bolt would change if the pipe grew in length.

On last weekend's trip from Tucson to Camp Verde, we drove non stop to the Sunset Point rest area on I-17, north of Phoenix. Just before getting to the rest area, there is a 2,000' climb in about seven miles. I figured the exhaust system would be good and hot when we got there. As soon as I got parked, I went out and looked at the bolt. It was dead vertical, indicating no expansion, lengthwise, anyway.

I am still going to leave the bolt somewhat loose just to allow for some additional movement. I don't think expansion is an issue. It appears to be minimal at best.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member

[Updated on: Sun, 24 March 2013 17:49]

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Re: [GMCnet] Exhaust System Advice Please? [message #202572 is a reply to message #202571] Sun, 24 March 2013 18:07 Go to previous messageGo to previous message
Dennis S is currently offline  Dennis S   United States
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Registered: November 2005
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Carl S. wrote on Sun, 24 March 2013 17:47

Dennis S wrote on Fri, 08 March 2013 12:00

Carl S. wrote on Fri, 08 March 2013 12:55

I went ahead and put a bracket on the tailpipe. It is almost identical to the one some PO had added to my old exhaust system. I thought it was a good idea. Here are some pics:

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html

http://www.gmcmhphotos.com/photos/misc-gmc/p47944-tail-pipe-hanger-brack.html


Carl,

Any idea how much the exhaust system expands and moves towards the rear of the coach? I ask because I thought that was the reason GMC went to the silicone rings with slip pipe.

Dennis



Dennis (and anyone else who is interested),

In order to allow for any possible expansion on the length of the exhaust pipe, I loosened the bolt on my "custom" rear tailpipe hanger, and double nutted it. I wanted to see if the pipes were expanding, in length, and figured the angle of the bolt would change if the pipe grew in length.

On last weekend's trip from Tucson to Camp Verde, we drove non stop to the Sunset Point rest area on I-17, north of Phoenix. Just before getting to the rest area, there is a 2,000' climb in about seven miles. I figured the exhaust system would be good and hot when we got there. As soon as I got parked, I went out and looked at the bolt. It was dead vertical, indicating no expansion, lengthwise, anyway.

I am still going to leave the bolt somewhat loose just to allow for some additional movement. I don't think expansion is an issue. It appears to be minimal at best.


Carl,

Thank you for the follow up.

My 73 has the early style pipe hangers and I had wondered about any advantage in moving to the silicone donuts -- may not be a concern.

Regards,
Dennis


Dennis S
73 Painted Desert 230
Memphis TN Metro
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