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Exhaust pipe replacement [message #319072] Thu, 15 June 2017 16:37 Go to next message
Matt Colie is currently offline  Matt Colie   United States
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Well, I did do a search of the forum, but I didn't find anything.

Is replacing the exhaust pipe from the Y to the back something you would do again with the coach on jack stands?

There are many times I have gone and done a job and later thought that I really should have hired that one out.
I will be working on a hard floor, but without a lot of spare room.

Second question, Should I order in the silicon bearings before I start?

Thanks

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Exhaust pipe replacement [message #319075 is a reply to message #319072] Thu, 15 June 2017 17:16 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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Matt

Are you going to be installing a 3 inch pipe? On a 26 ft 73 I experienced a lack of clearance in the frame openings for a 3 inch and had to grind/file the opening.

Early 1973 coaches had hangers not the silicone bearings.

I'd be inclined to order the silicone donuts just-in-case. I have seen some that looked ok until removed. As I recall one of the bolts retaining the silicone bearing holder was about 1/4 inch longer because of the double frame.

It wasn't too bad doing it on jack stands. I did it at the mini storage.

Hope this helps.

Dennis



Matt Colie wrote on Thu, 15 June 2017 16:37
Well, I did do a search of the forum, but I didn't find anything.

Is replacing the exhaust pipe from the Y to the back something you would do again with the coach on jack stands?

There are many times I have gone and done a job and later thought that I really should have hired that one out.
I will be working on a hard floor, but without a lot of spare room.

Second question, Should I order in the silicon bearings before I start?

Thanks

Matt



Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: Exhaust pipe replacement [message #319096 is a reply to message #319075] Thu, 15 June 2017 23:29 Go to previous messageGo to next message
Hal StClair   United States
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Piece of cake Matt. Everything just slips out the back. Just did it last week, took about an hour and a half along with swapping the heat shields. Of course I used bands instead of U bolts. Can't comment on the muffler bearings though.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: [GMCnet] Exhaust pipe replacement [message #319106 is a reply to message #319096] Fri, 16 June 2017 09:07 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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on my 75 transmode it went pretty easy, if you can get under it you can do it, the y pipe is pretty far in, you can't reach it from the edge IIRC.

and yes the pipe just slides in from the back, very easy.

My donuts were fine and were 3" already.

________________________________
From: Gmclist on behalf of Hal StClair
Sent: Thursday, June 15, 2017 11:29:30 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Exhaust pipe replacement

Piece of cake Matt. Everything just slips out the back. Just did it last week, took about an hour and a half along with swapping the heat shields. Of
course I used bands instead of U bolts. Can't comment on the muffler bearings though.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230

1974 Eagle Bus 45',w/slideout

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Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
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Re: [GMCnet] Exhaust pipe replacement [message #319132 is a reply to message #319106] Fri, 16 June 2017 19:56 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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While I do appreciate the input, this job has been a serious SumnaBitch.....
I am able to get the coach to a ride height of 20+ and that makes working under it possible. I wish I had though about this at Blain's.
I could not separate the long run from the Y-pipe without a brutal chisel job. It did not help that some prior person had laid a tack weld at the joint. Cleaning out the end of the Y is going to be fun, but I have done similar before. (Grind it thin in one place and hit it with a chisel so it rolls up.)

The long pipe will still not slide out. With a hammer it will not slide out.
Next, I am going to disassemble the supports and hope that I can slide them in pieces and get the pipe loose. The tail end of it is rotten so I cannot pull it and have it stay together.

I am not going to replace it with 3" because that won't actually get my anything and I don't want to change the Y. I guess I am going to get so 3" to make the sleeves, but I still don't know how long the long run needs to be or how I am going to bring it home in an old Honda.

When done, I will be sure to let you know.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Exhaust pipe replacement [message #319146 is a reply to message #319132] Sat, 17 June 2017 01:13 Go to previous messageGo to next message
Hal StClair   United States
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A sawzall is your friend, little pieces are a lot simpler to get out and no sparks to get something nasty going under there!
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: [GMCnet] Exhaust pipe replacement [message #319147 is a reply to message #319146] Sat, 17 June 2017 06:55 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Bring it home in two pieces and join the resulting joint with a band clamp. Or, tie it along the outside of the Honda, resting on the rear view mirror and roll down rear window, resting pipe on a section of 2x4. Drive carefully.
Always fun to bring home long pieces of material. Look at some of the photos that are posted out of Southeast Asia.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Exhaust pipe replacement [message #319150 is a reply to message #319147] Sat, 17 June 2017 08:19 Go to previous messageGo to next message
GMC.LES is currently offline  GMC.LES   United States
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A couple of pillows and some rope. Tie the tubing to your roof and go.

Les Burt
Montreal
'75 Eleganza 26'


> On Jun 17, 2017, at 7:55 AM, Thomas Phipps wrote:
>
> Bring it home in two pieces and join the resulting joint with a band clamp. Or, tie it along the outside of the Honda, resting on the rear view mirror
> and roll down rear window, resting pipe on a section of 2x4. Drive carefully.
> Always fun to bring home long pieces of material. Look at some of the photos that are posted out of Southeast Asia.
> Tom, MS II
> --
> 1975 GMC Avion
> KA4CSG
>
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Re: Exhaust pipe replacement [message #319152 is a reply to message #319072] Sat, 17 June 2017 08:37 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Use an air grinder to cut slots in the outer pipe at 0 and 180. Then take a 1" putty knife and hammer in the joint in small steps working around. In a just a few hours you will have expanded the outer pipe to free it ftom the inner. Fun.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Exhaust pipe replacement [message #319153 is a reply to message #319072] Sat, 17 June 2017 08:42 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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PS stock is 2.5" for sure because I have NOS GM long exh pipes and tail pipe and put a caliper on it. You probably know that but GM did use 2.75 on some vehicles. Gateway had the aluminized GM parts back when I got the TZE so I grabbed them.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Exhaust pipe replacement [message #319155 is a reply to message #319152] Sat, 17 June 2017 09:35 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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JohnL455 wrote on Sat, 17 June 2017 09:37
Use an air grinder to cut slots in the outer pipe at 0 and 180. Then take a 1" putty knife and hammer in the joint in small steps working around. In a just a few hours you will have expanded the outer pipe to free it ftom the inner. Fun.

The outside is the Y pipe. I want to keep that.
What I will do is go inside with a die grinder and thin the part that is stuck in there still until I can hit it with a chisel and roll it smaller. Then I will put an expander in the open end to make it round again and undo the damage the U-clamp did.

Having owned more than a few strange cars, I am very familiar with salvaging as much of the system as I can.

It looks like I am going to have to find the 2-1/2 pipe locally, and enough 3" to make new sleeves for the support. I'm sure I could drive up to Cinnabar and pick up the part, but that would be both costly and time consuming. This isn't rocket surgery, it's just a pain.

I am reminded of the VW shop book that says,"Remove the nut and slip the rear brake drum off the spline." Yeah Right......

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Exhaust pipe replacement [message #319157 is a reply to message #319146] Sat, 17 June 2017 09:55 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Hal StClair wrote on Sat, 17 June 2017 02:13
A sawzall is your friend, little pieces are a lot simpler to get out and no sparks to get something nasty going under there!
Hal

Hal,

I actually got out the Sawzall, but I cannot get the metal cutting blades that I have to fit so that there will be no damage to other parts that I really want to keep. My real problem seem to be in the forward of the two supports. PO had the coach undercoated when he brought it to Michigan and I believe that is why it won't slide. I am hoping that by disassembling that support I can make the silicon rubber ring slide. If that works, I will just have to remember to thread the parts back on a assembly time.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Exhaust pipe replacement [message #319158 is a reply to message #319155] Sat, 17 June 2017 09:58 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Matt, When I was redoing mine, the local exhaust / muffler shop had both 2.5" and 3" in stock. I had him bend me a few pieces and then I took them home for installation. You ought to be able to find what you need locally.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Exhaust pipe replacement [message #319161 is a reply to message #319157] Sat, 17 June 2017 11:02 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Silicone spray on the silicone rubber ring will make sliding it on the pipe a hundred times easier. When I need to separate exhaust pipe and must keep the outside pipe, I use the torch to get the outside pipe glowing nice and red before pulling,twisting, and wrenching the inner pipe. One of them needs to be solidly mounted and the outer pipe kept red hot anywhere it is crimped so the inner pipe can expand it during your wrenching, twisting, cursing, and tugging on it.

I have also used the reverse sardine can approach with the inner pipe cut off, a screwdriver driven in between the pipes, and a strong set of needle nose or flat duck-bill pliers to twist the inner pipe around itself until it is small enough to remove. Torch is handy during that operation too, if you have one.


Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Exhaust pipe replacement [message #319162 is a reply to message #319161] Sat, 17 June 2017 11:09 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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I get my exhaust pipe from a place I used to work at, a local automotive shop, and they get it from a commercial supplier, Chesapeake rim and wheel (CRW). I have seen it at the NAPA store before too. Comes in 10 ft lengths, think it was $2.50/ft for 2.5 inch last time I got some a few years ago.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Exhaust pipe replacement [message #319165 is a reply to message #319162] Sat, 17 June 2017 12:05 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Yes, 10 foot lengths is standard. And 10 foot is just right if you are going to the rear muffler.
Midas Muffler is the largest producer of pipes. I bought my 10 foot from them years back.

Emery Stora
77 Kingsley
Frederick, CO

> On Jun 17, 2017, at 10:09 AM, Terry wrote:
>
> I get my exhaust pipe from a place I used to work at, a local automotive shop, and they get it from a commercial supplier, Chesapeake rim and wheel
> (CRW). I have seen it at the NAPA store before too. Comes in 10 ft lengths, think it was $2.50/ft for 2.5 inch last time I got some a few years ago.
> --
> Terry Kelpien
>
> ASE Master Technician
>
> 73 Glacier 260
>
> Smithfield, Va.
>
>
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Re: [GMCnet] Exhaust pipe replacement [message #319171 is a reply to message #319165] Sat, 17 June 2017 14:34 Go to previous messageGo to next message
GMC.LES is currently offline  GMC.LES   United States
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Matt,
I often use an acetylene cutting torch to carefully cut a slit on the inside pipe before removal. I have never damaged the outer pipe enough for there to be any concern. The rust between the pipes provides some insulation, allowing the inner pipe to heat up and cut before the outer gets hot enough to be damaged. I've saved many a muffler this way. It just takes a bit of finess with the torch. Best of all, most of the cutting slag gets blown into the pipe, and not across your congested shop floor, possibly presenting fire risk.

However you decide to slit the inner pipe to remove it, you will most likely still need to expand the outer so you can fit a new piece. Hopefully you have an expander. If not, patience and a torch will be your next best friends.

Les Burt
Montreal
'75 Eleganza 26'


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Re: [GMCnet] Exhaust pipe replacement [message #319175 is a reply to message #319171] Sat, 17 June 2017 16:21 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Les Burt[1
wrote on Sat, 17 June 2017 15:34]Matt,
I often use an acetylene cutting torch to carefully cut a slit on the inside pipe before removal. I have never damaged the outer pipe enough for there to be any concern. The rust between the pipes provides some insulation, allowing the inner pipe to heat up and cut before the outer gets hot enough to be damaged. I've saved many a muffler this way. It just takes a bit of finess with the torch. Best of all, most of the cutting slag gets blown into the pipe, and not across your congested shop floor, possibly presenting fire risk.

However you decide to slit the inner pipe to remove it, you will most likely still need to expand the outer so you can fit a new piece. Hopefully you have an expander. If not, patience and a torch will be your next best friends.

Les Burt
Montreal
'75 Eleganza 26'

Les,

I have used an acetylene torch for a lot of exhaust work too, but in this case, the proximity to the fuel tanks makes that less attractive. I can do this all cold, but I was hoping someone had answers and experience to make it easier.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Exhaust pipe replacement [message #319178 is a reply to message #319175] Sat, 17 June 2017 17:02 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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Matt

What about cutting off the Y pipe and having the muffler shop make an angled piece enlarged on both ends?

Not sure how long the cut off could be to allow wiggle room to install.

Dennis


Matt Colie wrote on Sat, 17 June 2017 16:21
Les Burt[1
wrote on Sat, 17 June 2017 15:34]Matt,
I often use an acetylene cutting torch to carefully cut a slit on the inside pipe before removal. I have never damaged the outer pipe enough for there to be any concern. The rust between the pipes provides some insulation, allowing the inner pipe to heat up and cut before the outer gets hot enough to be damaged. I've saved many a muffler this way. It just takes a bit of finess with the torch. Best of all, most of the cutting slag gets blown into the pipe, and not across your congested shop floor, possibly presenting fire risk.

However you decide to slit the inner pipe to remove it, you will most likely still need to expand the outer so you can fit a new piece. Hopefully you have an expander. If not, patience and a torch will be your next best friends.

Les Burt
Montreal
'75 Eleganza 26'

Les,

I have used an acetylene torch for a lot of exhaust work too, but in this case, the proximity to the fuel tanks makes that less attractive. I can do this all cold, but I was hoping someone had answers and experience to make it easier.

Matt



Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: [GMCnet] Exhaust pipe replacement [message #319181 is a reply to message #319175] Sat, 17 June 2017 17:07 Go to previous messageGo to previous message
GMC.LES is currently offline  GMC.LES   United States
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Matt,
Another idea would be an exhaust pipe chisel. Some are made for use with a pneumatic zip gun, while others are hand held and used with a large mallet.

They usually provide a fairly quick solution to pipe removal if you don't mind some noise and/or a bit of physical effort.

Google exhaust chisel for some images.

Most images will show use on an exterior pipe, but I've found they will also work on inside sleeves with some minor re-contouring.


Les Burt
Montreal
'75 Eleganza 26'


> On Jun 17, 2017, at 5:21 PM, Matt Colie wrote:
>
> Les Burt[1
>> wrote on Sat, 17 June 2017 15:34]Matt,
>> I often use an acetylene cutting torch to carefully cut a slit on the inside pipe before removal. I have never damaged the outer pipe enough for
>> there to be any concern. The rust between the pipes provides some insulation, allowing the inner pipe to heat up and cut before the outer gets hot
>> enough to be damaged. I've saved many a muffler this way. It just takes a bit of finess with the torch. Best of all, most of the cutting slag gets
>> blown into the pipe, and not across your congested shop floor, possibly presenting fire risk.
>>
>> However you decide to slit the inner pipe to remove it, you will most likely still need to expand the outer so you can fit a new piece. Hopefully
>> you have an expander. If not, patience and a torch will be your next best friends.
>>
>> Les Burt
>> Montreal
>> '75 Eleganza 26'
>
> Les,
>
> I have used an acetylene torch for a lot of exhaust work too, but in this case, the proximity to the fuel tanks makes that less attractive. I can do
> this all cold, but I was hoping someone had answers and experience to make it easier.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Still Loving OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
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